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G. Wiese und A. Mannaa 《Fresenius' Journal of Analytical Chemistry》1980,302(1):56-58
Zusammenfassung Durch dilatometrische Indizierung der Bromadditionsreaktion lassen sich olefinische Doppelbindungen quantitativ bestimmen. Bei mehrfach ungesättigten Verbindungen treten Diskontinuitäten in der Titrationskurve auf, die auf eine stufenweise Addition schließen lassen.
On dilatometrically indicated TitrationsXVII. Rapid dilatometrical determination of olefin double bonds by addition of bromine
Summary Olefin double bonds can be determined quantitatively by dilatometrical indication of the bromine addition reaction. Discontinuities occurring in the titration curve of conjugated unsaturated compounds suggest a stepwise addition.
Teil der Dissertation 相似文献
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The changes of the volume which appear during the titration of some metall ions with Titriplex III are continuously controlled by means of a dilatometer and are used for the determination of the end point of the reaction. Over a range of 0.1<×<15 mMol all determinations can be reproduced with a standard deviation of <0.2%. For the complex formation between Mg2+ and Titriplex III the dependence of the change of volume of the overall reaction on the concentration is discussed. 相似文献
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In this paper we extensively treat the following problems: When is a given graph a subgraph (resp. induced subgraph) of a hypercube and when is an ordered set a subdiagram (resp. induced subdiagram) of a Boolean lattice? We present characterizations for that in terms of suitable edge-colorings of the graphs and, for ordered sets, of their covering graphs. 相似文献
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Adam Kurpisz Monaldo Mastrolilli Claire Mathieu Tobias Mömke Victor Verdugo Andreas Wiese 《Mathematical Programming》2018,172(1-2):231-248
Sherali and Adams (SIAM J Discrete Math 3:411–430, 1990) and Lovász and Schrijver (SIAM J Optim 1:166–190, 1991) developed systematic procedures to construct the hierarchies of relaxations known as lift-and-project methods. They have been proven to be a strong tool for developing approximation algorithms, matching the best relaxations known for problems like Max-Cut and Sparsest-Cut. In this work we provide lower bounds for these hierarchies when applied over the configuration LP for the problem of scheduling identical machines to minimize the makespan. First we show that the configuration LP has an integrality gap of at least 1024/1023 by providing a family of instances with 15 different job sizes. Then we show that for any integer n there is an instance with n jobs in this family such that after \(\varOmega (n)\) rounds of the Sherali–Adams (\(\text {SA}\)) or the Lovász–Schrijver (\(\text {LS}_+\)) hierarchy the integrality gap remains at least 1024/1023. 相似文献
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Tim Schröder Lars-Peter Lauven Jutta Geldermann 《European Journal of Operational Research》2018,264(3):1005-1019
Biorefineries can provide a product portfolio from renewable biomass similar to that of crude oil refineries. To operate biorefineries of any kind, however, the availability of biomass inputs is crucial and must be considered during planning. Here, we develop a planning approach that uses Geographic Information Systems (GIS) to account for spatially scattered biomass when optimizing a biorefinery’s location, capacity, and configuration. To deal with the challenges of a non-smooth objective function arising from the geographic data, higher dimensionality, and strict constraints, the planning problem is repeatedly decomposed by nesting an exact nonlinear program (NLP) inside an evolutionary strategy (ES) heuristic, which handles the spatial data from the GIS. We demonstrate the functionality of the algorithm and show how including spatial data improves the planning process by optimizing a synthesis gas biorefinery using this new planning approach. 相似文献