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Dr. Thomas Lunkenbein Dr. Frank Girgsdies Anna Wernbacher Dr. Johannes Noack Dr. Gudrun Auffermann Akira Yasuhara Achim Klein‐Hoffmann Prof. Wataru Ueda Dr. Maik Eichelbaum Dr. Annette Trunschke Prof. Robert Schlögl Dr. Marc G. Willinger 《Angewandte Chemie (International ed. in English)》2015,54(23):6828-6831
Complex Mo,V‐based mixed oxides that crystallize in the orthorhombic M1‐type structure are promising candidates for the selective oxidation of small alkanes. The oxygen sublattice of such a complex oxide has been studied by annular bright field scanning transmission electron microscopy. The recorded micrographs directly display the local distortion in the metal oxygen octahedra. From the degree of distortion we are able to draw conclusions on the distribution of oxidation states in the cation columns at different sites. The results are supported by X‐ray diffraction and electron paramagnetic resonance measurements that provide integral details about the crystal structure and spin coupling, respectively. 相似文献
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D. Weigelt F. Schubert und F. Scheller 《Fresenius' Journal of Analytical Chemistry》1987,328(3):259-262
Summary Enzyme electrodes were assembled by coupling membrane-immobilized lactate monooxygenase and coimmobilized lactate monooxygenase and lactate dehydrogenase, respectively, to oxygen electrodes. The lactate monooxygenase sensor was used for lactate determination with the analyzer Glukometer as well as for sequential measurement of lactate and lactate dehydrogenase activity.The bienzyme electrode is applicable for determining lactate and pyruvate in one measuring cycle. The operational parameters of the optimized sensors like measuring range, relative standard deviation, measuring frequency, and stability were studied. Determinations in biological fluids correlated well with spectrophotometric reference methods. 相似文献
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S. Scheller 《Zeitschrift für Physik B Condensed Matter》1971,13(3):187-192
The two elementsχ′ yx andχ″ xx of the magnetic susceptibility tensor for the cubic ferromagnetic EuO are investigated at microwave frequencies. It is shown that these two elements coincide when the magnetic field is large enough to remove the domain structure within the sample. This is in coincidence with theoretical predictions and shows a certain structure of the Hamiltonian. The magnetic transition temperature is found to beT c=(69.2±0.2)°K in agreement with the result from specific heat measurement. 相似文献
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Rolf Russow Maik Veste Thomas Littmann 《Isotopes in environmental and health studies》2013,49(1):57-67
The variation of the natural 15N abundance is often used to evaluate the origin of nitrogen or the pathways of N input into ecosystems. We tried to use this approach to assess the main input pathways of nitrogen into the sand dune area of the north-western Negev Desert (Israel). The following two pathways are the main sources for nitrogen input into the system:
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Biological fixation of atmospheric nitrogen by cyanobacteria present in biological crusts and by N2-fixing vascular plants (e.g. the shrub Retama raetam);
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Atmospheric input of nitrogen by wet deposition with rainfall, dry deposition of dust containing N compounds, and gaseous deposition.
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