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161.
Piotr Gwiazda Agnieszka Świerczewska-Gwiazda Petra Wittbold Aleksandra Zimmermann 《Journal of Functional Analysis》2014
We consider scalar balance laws with a dissipative source term. The flux function may be discontinuous with respect to both the space variable x and the unknown quantity u. We formulate the definition of entropy weak solutions and provide existence and uniqueness to the considered problem. The problem is formulated in the framework of multi-valued mappings. The notion of entropy measure-valued solutions is used to prove the so-called contraction principle and comparison principle. 相似文献
162.
Operator splitting methods for a special class of nonlinear partial differential equations with delay are investigated. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
163.
Frank Lenzen Florian Becker Jan Lellmann Stefania Petra Christoph Schnörr 《Computational Optimization and Applications》2013,54(2):371-398
We introduce a class of adaptive non-smooth convex variational problems for image denoising in terms of a common data fitting term and a support functional as regularizer. Adaptivity is modeled by a set-valued mapping with closed, compact and convex values, that defines and steers the regularizer depending on the variational solution. This extension gives rise to a class of quasi-variational inequalities. We provide sufficient conditions for the existence of fixed points as solutions, and an algorithm based on solving a sequence of variational problems. Denoising experiments with spatial and spatio-temporal image data and an adaptive total variation regularizer illustrate our approach. 相似文献
164.
165.
Libuse Trnkova Ladislav Novotny Nuria Serrano Katerina Klosova Petra Polaskova 《Electroanalysis》2010,22(16):1873-1880
Elimination voltammetry with linear scan (EVLS) in connection with renewed mini‐ drop mercury electrodes provides valuable information about the character and kinetics of processes at electrode/electrolyte interfaces. Based on the experiment related to the hydrogen evolution, it is presented that the EVLS is more sensitive than other voltammetric methods. Using miniaturized mercury electrodes, the EVLS is capable of detecting the effect of spherical diffusion associated with both the scan rates and the size of an electrode drop. 相似文献
166.
167.
This paper concerns verification of the defect chemistry models of La1−xSrxCoO3−δ (LSC), involving the random defect model and the cluster defect model, against empirical data of oxygen nonstoichiometry.
It appears that the experimental data may well be explained within the random defect model. 相似文献
168.
Per J. Garegg Petra Ossowski Sabine Köpper Joachim Thiem 《Journal of carbohydrate chemistry》2013,32(1):59-65
The use of silver zeolite as a promoter for the preparation of β-linked 2-deoxygtycosides and disaccharides of biological relevance has been explored. Starting from benzoylated glycosyl bromides, the total yield of glycosides varies from 54 to 84% and the α:β ratio from 0.25 to 1.18. 相似文献
169.
Petra Frohberg Ingo SchulzeChristian Donner Fabian Krauth 《Tetrahedron letters》2012,53(34):4507-4509
Reaction of carbonyl substituted hydrazonoyl chlorides with amines usually leads to Z-configured amidrazone derivatives via nucleophilic substitution of the chlorine atom. Surprisingly, N,N-dimethylcarboxamide substituted hydrazonoyl chlorides yielded E-amidrazones when dialkylamines were used as nucleophilic reagent. The lipophilicities of the obtained amidrazones were found to be drastically reduced compared to their corresponding carboxanilides. 相似文献
170.
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