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61.
This contribution deals with the modelling and simulation of curing phenomena in adhesively bonded piezo metal composites which consists of a piezoelectric module enclosed by an adhesive layer which in turn is surrounded by two metal sheets. A short survey on the neccessary experimental investigations to characterise the adhesive's material behaviour is given and important aspects on the corresponding phenomenological modelling approach are presented. Both steps take into account the curing reaction, changes of volume, like chemical shrinkage, and inelastic mechanical behaviour which is temperature and curing dependent. Finally, the simulation strategy for the modelling within a finite element environment is depicted. By this, residual stresses, secondary deformations and loads on the piezo modules can be predicted, which is exemplified by a comparative study verifying a novel manufacturing strategy. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
62.
Univariate Gonarov polynomials arose from the Gonarov interpolation problem in numerical analysis.They provide a natural basis of polynomials for working with u-parking functions,which are integer sequences whose order statistics are bounded by a given sequence u.In this paper,we study multivariate Gonarov polynomials,which form a basis of solutions for multivariate Gonarov interpolation problem.We present algebraic and analytic properties of multivariate Gonarov polynomials and establish a combinatorial relation with integer sequences.Explicitly,we prove that multivariate Gonarov polynomials enumerate k-tuples of integers sequences whose order statistics are bounded by certain weights along lattice paths in Nk.It leads to a higher-dimensional generalization of parking functions,for which many enumerative results can be derived from the theory of multivariate Gonarov polynomials. 相似文献
63.
Sebastien Graule Mark Rudolph Wenting Shen J. A. Gareth Williams Dr. Christophe Lescop Dr. Jochen Autschbach Prof. Jeanne Crassous Dr. Régis Réau Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(20):5976-6005
Aza[n]helicene phosphole derivatives have been prepared from aza[n]helicene diynes by the Fagan–Nugent route. Their photophysical properties (UV/Vis absorption and emission behavior) have been evaluated. Their behavior as P,N chelates towards coordination to PdII and CuI has been investigated: metal–bis(aza[n]helicene phosphole) assemblies are formed by a highly stereoselective coordination process, as demonstrated by X‐ray crystallography. An aza[6]helicene phosphole bearing an enantiopure helicene part has been obtained, which allows the preparation of enantiopure PdII and CuI complexes with original topologies and high molar rotation (MR) and circular dichroism (CD). The structure–property relationship established from the experimental data has been studied in detail by theoretical studies (TDDFT calculations of UV/Vis, CD, and MR). Aza[n]helicene phosphole derivatives show π conjugation extended over the entire molecule, and its influence on the MR of aza[6]helicene phosphole 5 c has been demonstrated. Finally, it has been shown that the nature of the metal (coordination geometry and electronic interaction) can have a great impact on the amplitude of the chiroptical properties in metal–bis(aza[n]helicene phosphole) assemblies. 相似文献
64.
Jan P. Weyrauch Dr. A. Stephen K. Hashmi Prof. Dr. Andreas Schuster Dipl.‐Chem. Tobias Hengst Dipl.‐Chem. Stefanie Schetter Anna Littmann Dipl.‐Chem. Matthias Rudolph Dr. Melissa Hamzic Dr. Jorge Visus Jan W. Bats Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(3):956-963
The substrate scope, the mechanistic aspects of the gold‐catalyzed oxazole synthesis, and substrates with different aliphatic, aromatic, and functional groups in the side chain were investigated. Even molecules with several propargyl amide groups could easily be converted, delivering di‐ and trioxazoles with interesting optical properties. Furthermore, the scope of the gold(I)‐catalyzed alkylidene synthesis was investigated. Further functionalizations of these isolable intermediates of the oxazole synthesis were developed and chelate ligands can be obtained. The use of Barluenga’s reagent offers a new and mild access to the synthetically valuable iodoalkylideneoxazoles from propargylic amides, this reagent being superior to other sources of halogens. 相似文献
65.
Gerd-Volker Rschenthaler Rainer Bohlen Rudolph Francke Joachim Heine Reinhard Schmutzler 《无机化学与普通化学杂志》1986,533(2):18-22
Bis(trimethylsilyl)phosphates of 1,1,1,4,4,4-Hexafluoro-2,3-bis(trifluoromethyl)-2,3-butanediol and 1,1,1,3,3-Pentafluoro-2-propenol The monocyclic phosphorane (EtO)3P[OC(CF3)2C(CF3)2O] 1 was hydrolized to give a mixture of an acyclic and a cyclic phosphate, 3 and 4 . The trihydroxyphosphorane 2 could not be obtained. Iodotrimethylsilane 6 converts 1 into the silylated derivative of 4 which was found also besides (Me3SiO)2P(O)OC(CF3)2C(CF3)2OSiMe3 8 in the reaction of 3 and 4 with Me3SiCl/(Me3Si)2NH. (Me3SiO)3P 10 and hexafluoroacetone did not yield the tris(trimethylsiloxy)phosphorane 5 , but the phosphonate 11 which gave (Me3SiO)2P(O)OC(CF3) ? CF2 12 upon heating with the loss of fluorotrimethylsilane. 相似文献
66.
Larry Rudolph 《纯数学与应用数学通讯》1995,48(9):1157-1171
In this paper, we examine several issues of bit-parallel free space optical communication such as arbitration operations, fault tolerance, and connector alignment. © 1996 John Wiley & Sons, Inc. 相似文献
67.
68.
Carlos Camacho‐Camacho Monique Biesemans Ingrid Verbruggen Rudolph Willem 《应用有机金属化学》2005,19(3):343-346
The reactivity and catalytic potential of the tin salicylaldoximate cluster [(Me2Sn)2(Me2SnO)(OCH3) (HONZO)(ONZO)] ( 1 ), with HONZOH = o‐HON?CH? C6H4OH, on the acylation reaction of various alcohols with ethyl acetate is reported. The catalyst is active toward primary and unhindered secondary alcohols, but inefficient toward tertiary and secondary bulky alcohols and phenols. A possible mechanism for the transesterification reaction catalyzed by 1 , accounting for the influence of steric factors, is proposed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
69.
Dr. Rudolph Wegscheider 《Monatshefte für Chemie / Chemical Monthly》1892,13(1):252-267
Ohne Zusammenfassung 相似文献
70.