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41.
We present a high-level quantum chemical study of possible reaction mechanisms associated with the catalytic decomposition of urea by a bioinorganic mimetic of the dinickel active site of urease. We chose the phthalazine-dinickel complexes of Lippard and co-workers, because these mimetics have been shown to hydrolytically degrade urea. High-level quantum chemical methodologies were utilized to identify stable intermediates and transition-state structures along several possible reaction pathways. The computed results were then used to further analyze what may occur in the active site of urease. Valuable information on the latter has been extracted from experimental data, computational approaches, and unpublished molecular dynamics simulations. On the basis of these comparative studies, we propose that both the elimination and hydrolytic pathways may compete for urea decomposition in the active site of urease. 相似文献
42.
43.
James L. Merz 《Fiber and Integrated Optics》2013,32(2):143-157
Recent progress in the development of integrated optical circuits using the III-V compound semiconductors is reviewed. The application of double heterostructure configurations is emphasized, not only for optical sources, but also for detectors, with reference to both the A/GaAs/GaAs system and the InGaAsP quaternary. Devices utilizing periodic corrugations are described briefly, whereas alternate attempts to fabricate optical circuits by etching or sputtering techniques are discussed in more detail. Recent advances in processing techniques suitable for optical integration, such as reactive-ion etching, and the use of lasers or electron beams for device processing, are described. 相似文献
44.
45.
G. Merz 《Fresenius' Journal of Analytical Chemistry》1868,7(1):275-276
Ohne Zusammenfassung 相似文献
46.
R. Meurice J. Cartiaux W. H. Ross K. C. Beeson L. M. White A. R. Merz K. Scharrer H. Schorstein R. Brill M. Popp H. Westerhoff H. Terlet A. Briau F. Kaminski F. Erdheim K. D. Jacob L. F. Rader Jr. T. H. Tremearne J. Contzen W. Sauerlandt Commission technique permanente de la Répression des Fraudes 《Analytical and bioanalytical chemistry》1941,122(5-6):230-237
47.
F. Selmi und Gustav Merz 《Fresenius' Journal of Analytical Chemistry》1876,15(1):461-462
Ohne Zusammenfassung 相似文献
48.
F. Nydahl W. D. Troadwell W. H. Ross A. R. Merz K. D. Jacob und P. Krumholz 《Fresenius' Journal of Analytical Chemistry》1943,126(9):342-347
Ohne Zusammenfassung 相似文献
49.
M. Merz P. Reutler B. Büchner D. Arena J. Dvorak Y. U. Idzerda S. Tokumitsu S. Schuppler 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,51(3):315-319
O1s and Mn2p near-edge X-ray absorption spectroscopy on
La1-xSr1+xMnO4 (0 ≤x ≤0.5) single crystals shows that Sr doping does not
only provide holes to the system but also induces a continuous transfer of electrons from
out-of-plane d3z2-r2 to in-plane d3x2-r2/d3y2-r2 orbitals. Furthermore, a
non-vanishing electron occupation of in-plane dx2-y2 and out-of-plane d3z2-r2
orbitals is observed up to relatively high doping contents. These findings demonstrate that the
energy difference between all these orbital types has to be very small and manifest that the
orbital degree of freedom is determined not just by crystal field effects but also by orbital
coupling. Moreover, the doping-dependent transfer of spectral weight observed in the current data
identifies La1-xSr1+xMnO4 as a charge-transfer insulator. 相似文献
50.
T. Görler X. Lapillonne S. Brunner T. Dannert F. Jenko F. Merz D. Told 《Journal of computational physics》2011,230(18):7053-7071
The understanding and prediction of transport due to plasma microturbulence is a key open problem in modern plasma physics, and a grand challenge for fusion energy research. Ab initio simulations of such small-scale, low-frequency turbulence are to be based on the gyrokinetic equations, a set of nonlinear integro-differential equations in reduced (five-dimensional) phase space. In the present paper, the extension of the well-established and widely used gyrokinetic code GENE [F. Jenko, W. Dorland, M. Kotschenreuther, B.N. Rogers, Electron temperature gradient driven turbulence, Phys. Plasmas 7 (2000) 1904–1910] from a radially local to a radially global (nonlocal) version is described. The necessary modifications of both the basic equations and the employed numerical methods are detailed, including, e.g., the change from spectral methods to finite difference and interpolation techniques in the radial direction and the implementation of sources and sinks. In addition, code verification studies and benchmarks are presented. 相似文献