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991.
Schneider SK Julius GR Loschen C Raubenheimer HG Frenking G Herrmann WA 《Dalton transactions (Cambridge, England : 2003)》2006,(9):1226-1233
A series of cationic pyridinylidene and quinolinylidene complexes of chlorobis(triphenylphosphine)-nickel(II) were prepared by oxidative substitution of Ni(PPh3)4 with methylated chloropyridines or chloroquinolines. NMR as well as X-ray crystallographic studies confirmed the trans arrangement of the two phosphines in the products. Calculations, using suitable model compounds at the BP86/TZVP level, clearly differentiate between a standard imidazolylidene complex and new complexes of the NHC-type on the one hand, and new complexes classified as rNHC-types-with the heteroatom distant from the carbene carbon-on the other. The latter form significantly stronger bonds-mainly of an electrostatic nature-with the metal. 相似文献
992.
Knaup JM Köhler C Frauenheim T Blumenau AT Amkreutz M Schiffels P Schneider B Hennemann OD 《The journal of physical chemistry. B》2006,110(41):20460-20468
We calculate the minimum energy paths and reaction energies of the adsorption of the epoxide adhesive components diglycidylesterbisphenol A (DGEBA), diethyltriamine (DETA), and the adhesion promoter 3-aminopropylmethoxysilane (AMEO) at two different sites on a model of the native Al2O3 surface, using the nudged elastic band algorithm in conjunction with self-consistent charge-density functional based tight binding. Our results show that the chosen combination of methods is well suited to obtain an overview of the reaction mechanisms and kinetics of the adsorption of organic molecules on inorganic surfaces. The obtained MEP-s show that there is preference for the adsorption of the adhesion promoter, AMEO, over the resin, DGEBA, while the adsorption of the curing agent, DETA, is unfavorable. Our approach also gives an insight into the ranges of the mechanical and electronic influences of the adsorption process on the interface, which neither full ab initio methods nor force field approaches can provide. These results will help to develop a quantum mechanics-molecular mechanics multiscale embedding scheme for more detailed studies of organic/inorganic hybrid interface reactions. 相似文献
993.
Nicolas Chenavier Bruno Massé Dominique Schneider 《Stochastic Processes and their Applications》2018,128(5):1615-1634
We provide conditions on dependent and on non-stationary random variables ensuring that the mantissa of the sequence of products is almost surely distributed following Benford’s law or converges in distribution to Benford’s law. This is achieved through proving new generalizations of Lévy’s and Robbins’s results on distribution modulo 1 of sums of independent random variables. 相似文献
994.
Ivan Žulj Sergej Kramer Michael Schneider 《European Journal of Operational Research》2018,264(2):653-664
Given a set of customer orders and a routing policy, the goal of the order-batching problem?(OBP) is to group customer orders to picking orders (batches) such that the total length of all tours through a rectangular warehouse is minimized. Because order picking is considered the most labor-intensive process in warehousing, effectively batching customer orders can result in considerable savings. The OBP is NP-hard if the number of orders per batch is greater than two, and the exact solution methods proposed in the literature are not able to consistently solve larger instances. To address larger instances, we develop a metaheuristic hybrid based on adaptive large neighborhood search and tabu search, called ALNS/TS. In numerical studies, we conduct an extensive comparison of ALNS/TS to all previously published OBP methods that have used standard benchmark sets to investigate their performance. ALNS/TS outperforms all comparison methods with respect to both average solution quality and run-time. Compared to the state-of-the-art, ALNS/TS shows the clearest advantages on the larger instances of the existing benchmark sets, which assume a higher number of customer orders and higher capacities of the picking device. Finally, ALNS/TS is able to solve newly generated large-scale instances with up to 600 customer orders and six articles per customer order with reasonable run-times and convincing scaling behavior and robustness. 相似文献
995.
Vitor Marino Schneider 《Optics Communications》1999,160(4-6):230-234
Passive optical structures are simulated by the method of lines using an eigenvalue routine based on the Arnoldi method, where its time efficiency is verified. A systematic approach is developed using an adaptive routine to determine selected radiation modes that must be taken into account in order to achieve a certain degree of accuracy. 相似文献
996.
J. Houben Julius Meyer F. P. Treadwell F. Heeren H. G. Martin Cl. E. Williams Arvid E. Anderson C. E. Sims B. M. Larsen E. Terres A. Pongracz H. C. M. Ingeberg F. Foerster V. Herold E. S. Peck G. Frerichs V. Coblentz O. B. May Edgar Thompson Steel Works A. D. Horlück A. Eberhard E. Schmidt Fr. Wüst N. Kirpach L. Schneider J. Parry J. J. Morgan und E. Diepschlag 《Fresenius' Journal of Analytical Chemistry》1927,71(8):297-311
Ohne Zusammenfassung 相似文献
997.
R. Schneider 《Fresenius' Journal of Analytical Chemistry》1885,24(1):648
Ohne Zusammenfassung 相似文献
998.
G. Schacherl H. Helbing F. W. Passmore Fr. Seiler Franz Fritzsche & Co. G. A. Raupenstrauch A. Schneider C. Engler E. Dieckhoff W. Reuss G. Chlopin M. E. Merklen Béhal Choay Pio Marfori B. Fischer Thomas Rieck M. Adrian Schmidt D. Vitali B. Hafner W. Kreissl Glücksmann C. Monheim J. Bougault und Fréd. Seiler 《Fresenius' Journal of Analytical Chemistry》1901,40(9):615-628
Ohne Zusammenfassung 相似文献
999.
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