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排序方式： 共有950条查询结果，搜索用时 0 毫秒
101.
Jan Prüss 《Archiv der Mathematik》2017,108(3):301-311
Second order elliptic operators and their parabolic counterparts are studied in the case of complete boundary degeneration of the leading order coefficients in the presence of a strong outward pointing drift. It is shown that the problem generates a positive analytic \(C_0\)-semigroup with maximal \(L_p\)-regularity in \(L_q\)-spaces. This result is based on hard analysis estimates for integral operators in combination with modern functional analytic tools like \({\mathcal R}\)-boundedness and the operator-valued functional calculus. 相似文献
102.
Der Präsident des Kongresses F. H. Müller 《Rheologica Acta》1961,1(4-6):331-331
Ohne Zusammenfassung 相似文献
103.
Heinz Prüfer 《Mathematische Zeitschrift》1923,17(1):35-61
Ohne Zusammenfassung 相似文献
104.
Heinz Prüfer 《Mathematische Zeitschrift》1925,22(1):222-249
Ohne Zusammenfassung 相似文献
105.
Dielectrophoresis (DEP) is an AC electrokinetic effect that is proven to be effective for the immobilization of not only cells, but also of macromolecules, for example, antibodies and enzyme molecules. In our previous work, we have already demonstrated the high catalytic activity of immobilized horseradish peroxidase after DEP. To evaluate the suitability of the immobilization method for sensing or research in general, we want to test it for other enzymes, too. In this study, glucose oxidase (GOX) from Aspergillus niger was immobilized on TiN nanoelectrode arrays by DEP. Fluorescence microscopy showed the intrinsic fluorescence of the immobilized enzymes flavin cofactor on the electrodes. The catalytic activity of immobilized GOX was detectable, but a fraction of less than 1.3% of the maximum activity that was expected for a full monolayer of immobilized enzymes on all electrodes was stable for multiple measurement cycles. Therefore, the effect of DEP immobilization on the catalytic activity strongly depends on the used enzyme. 相似文献
106.
Malte Rosenthal Franziska Pfeiffer Günter Mayer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(31):10864-10868
107.
108.
Davide Di Marino Tim Jestel Caroline Marks Dr. Jörn Viell Malte Blindert Dr. Stefanie M. A. Kriescher Prof. Antje C. Spiess Prof. Matthias Wessling 《ChemElectroChem》2019,6(5):1434-1442
Facing the challenge of lignin valorization is one of the unsolved key steps for a sustainable and economically feasible biorefinery. Several processes were developed with the aim of producing value-added compounds from lignin. Thermal, enzymatic, and catalytic processes represent common techniques for lignin valorization. However, expensive catalysts or enzymes and harsh conditions hampered the implementation of these methodologies on an industrial scale. Here, we propose the utilization of a simple “swiss-roll” electrochemical reactor for the production of valuable carboxylic acids. We showcase that production of phenolic compounds, such as vanillin, is hindered by the electrochemical mechanism. Additionally, electrochemical stability experiments of possible products showed high reactivity of vanillin against the low reactivity of mono- and dicarboxylic acids. Simultaneously, the electrochemical process leads to stable carboxylic acids with high yields of 6.4, 26.8, and 4.2 % for oxalic, formic, and acetic acids, respectively, thus representing a competitive alternative to the catalytic and hydrothermal degradation process for the production of carboxylic acids. 相似文献
109.
Dr. Julian J. Holstein Priv.‐Doz. Dr. Birger Dittrich Miriam Simon Dr. Sylvain Prévost Prof. Dr. Michael Gradzielski Prof. Dr. Guido H. Clever 《Angewandte Chemie (International ed. in English)》2018,57(41):13652-13656
A series of metal‐mediated cages, having multiple cavities, was synthesized from PdII cations and tris‐ or tetrakis‐monodentate bridging ligands and characterized by NMR spectroscopy, mass spectrometry, and X‐ray methods. The peanut‐shaped [Pd3L14] cage deriving from the tris‐monodentate ligand L1 could be quantitatively converted into its interpenetrated [5Cl@Pd6L18] dimer featuring a linear {[Pd‐Cl‐]5Pd} stack as an unprecedented structural motif upon addition of chloride anions. Small‐angle neutron scattering (SANS) experiments showed that the cigar‐shaped assembly with a length of 3.7 nm aggregates into mono‐layered discs of 14 nm diameter via solvophobic interactions between the hexyl sidechains. The hepta‐cationic [5Cl@Pd6L18] cage was found to interact with polyanionic oligonucleotide double‐strands under dissolution of the aggregates in water, rendering the compound class interesting for applications based on non‐covalent DNA binding. 相似文献
110.
Malte Braack Martin F. Quaas Benjamin Tews Boris Vexler 《Journal of Optimization Theory and Applications》2018,178(3):950-972
The behavior of a fishing fleet and its impact onto the biomass of fish can be described by a nonlinear parabolic diffusion–reaction equation. Looking for an optimal fishing strategy leads to a non-convex optimal control problem with a bilinear control action. In this work, we present such an optimal control formulation, prove its well-posedness and derive first- and second-order optimality conditions. These results provide a basis for tailored finite element discretization as well as for Newton type optimization algorithms. First numerical test problems show typical features as so-called No-Take-Zones and maximal fishing quota (total allowable catches) as parts of an optimal fishing strategy. 相似文献