732 research outputs found
Fallstudien: kritische einschatzung
Das Ziel dieses Artikels ist es, das Wesentliche bei der Fallstudie festzustellen und eine kritische Einschatzung dieser Methode durchzufuhren. Infolgedessen wird zunachst der Versuch gemacht, den Begriff des Falls und der Fallstudie darzustellen. Anschlie?end werden die Vor- und Nachteile, d.h. die Moglichkeiten und die Grenzen der Fallstudie diskutiert und entsprechende Folgerungen gemacht.Статья посвящена проблеме определения "кейса" и "метода кейсов", а также возможностям применения и недостаткам данного метода
Gyrokinetic analysis and simulation of pedestals, to identify the culprits for energy losses using fingerprints
Fusion performance in tokamaks hinges critically on the efficacy of the Edge
Transport Barrier (ETB) at suppressing energy losses. The new concept of
fingerprints is introduced to identify the instabilities that cause the
transport losses in the ETB of many of today's experiments, from widely posited
candidates. Analysis of the Gyrokinetic-Maxwell equations, and gyrokinetic
simulations of experiments, find that each mode type produces characteristic
ratios of transport in the various channels: density, heat and impurities.
This, together with experimental observations of transport in some channel, or,
of the relative size of the driving sources of channels, can identify or
determine the dominant modes causing energy transport. In multiple ELMy H-mode
cases that are examined, these fingerprints indicate that MHD-like modes are
apparently not the dominant agent of energy transport; rather, this role is
played by Micro-Tearing Modes (MTM) and Electron Temperature Gradient (ETG)
modes, and in addition, possibly Ion Temperature Gradient (ITG)/Trapped
Electron Modes (ITG/TEM) on JET. MHD-like modes may dominate the electron
particle losses. Fluctuation frequency can also be an important means of
identification, and is often closely related to the transport fingerprint. The
analytical arguments unify and explain previously disparate experimental
observations on multiple devices, including DIII-D, JET and ASDEX-U, and
detailed simulations of two DIII-D ETBs also demonstrate and corroborate this
4-Methoxy-N-(4-nitrobenzyl)aniline
In the title compound, C14H14N2O3, the nitro group is nearly coplanar with the benzene ring to which it is bonded [dihedral angle = 1.70 (2)°], and this ring is para-substituted by the aminomethylene group. The dihedral angle between the benzene rings is 57.8 (1)°. The crystal structure is stabilized by N—H⋯O and C—H⋯O hydrogen bonds and weak C—H⋯π interactions are also observed
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