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91.
Mn inclusion in the oxide based diluted magnetic semiconductor Zn1−x
Mn
x
O (x = 0.04, 0.06, 0.08, and 0.10) grown by standard high temperature solid state reaction technique has been studied. The local
and average structure of Zn1−x
Mn
x
O was characterized by the super resolution technique maximum entropy method and pair distribution function analysis using
the X-ray powder data. Magnetic studies on this material using a Vibrating Sample Magnetometer were also carried out to ascertain
the doping level in Zn1−x
Mn
x
O. 相似文献
92.
We demonstrate polarization-sensitive measurement of the modal content of waveguides by generalizing the classic rotating wave-plate-based polarimeter to wide-field optical low-coherence interferometry. The spatial phases of the modes are retrieved with principal component analysis. By applying this polarization-sensitive cross-correlation (C2) imaging technique to the characterization of a few-mode fiber, we reveal that different modes experience distinct bend-induced birefringence in optical fibers. This polarization-resolved C2 imaging is well suited for analyzing the impact of polarization on wave propagation in high-power fiber lasers as well as in mode-division-multiplexed communications systems. 相似文献
93.
Parthasarathy Ramachandran 《理论物理通讯》2009,52(4):646-652
In this article, we study traffic flow in the presence ofspeed breaking structures. The speed breakers are typically used toreduce the local speed of vehicles near certain institutions such asschools and hospitals. Through a cellular automata model we study the impact of such structures on global traffic characteristics. The simulation results indicate that the presence of speed breakers could reduce the global flow under moderate global densities. However, under low and high global density traffic regime the presence of speed breakers does not have an impact on the global flow. Further the speed limit enforced by the speed breaker createsa phase distinction. For a given global density and slowdown probability, as the speed limit enforced by the speed breaker increases, the traffic moves from the reduced flow phase to maximum flow phase. This underlines the importance of proper design of these structures to avoid undesired flow restrictions. 相似文献
94.
95.
96.
A method is suggested to determine experimentally whether the state of a spin system is oriented or non-oriented by measuring
the angular distribution,I and the circular polarization asymmetry,A
c of the photons emitted by the system. These also provide enough data to determine the density matrix completely. 相似文献
97.
We study the group of extensions in the category of Drinfeld modules and Anderson's t-modules, and we show in certain cases that this group can itself be given the structure of a t-module. Our main result is a Drinfeld module analogue of the Weil-Barsotti formula for abelian varieties. Extensions of general t-modules are also considered, in particular extensions of tensor powers of the Carlitz module. We motivate these results from various directions and compare to the situation of elliptic curves. 相似文献
98.
Siddharth Ramachandran 《光学学报》2003,23(Z1)
Dispersion compensation with few-mode fibers is emerging as a promising technique that can provide full dispersion and dispersion-slope compensation. The inherent modal path diversity of these fibers allows implementation of static as well as tunable dispersion management schemes. In addition, the low nonlinearityof this technology can improve system OSNR, leading to enhancements in transmission distances. 相似文献
99.
Summary A new and sensitive analytical technique has been developed for the simultaneous determination of six aromatic amines. It is based on the differential migration of coloured derivatives formed by the reaction of the diazotized amines with 6-amino-1-naphthalene-3-sulphonic acid on a silica gel plate. The concentration is evaluated by colour comparison or by spectrophotometry under the influence of a temperature gradient. The method is highly reproducible and has been applied to the determination of amines in environmental samples. Standard deviations are 4.6–7.3%. 相似文献
100.