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基于EAST超导托卡马克实验装置,给出了HALO电流计算方法和计算过程,并通过自由能方法模拟得出了等离子体电流、HALO电流在等离子体破裂过程中随时间的演化过程。 相似文献
916.
Laser performance of 1064 nm domestic Nd:YAG ceramic lasers for 885 nm direct pumping and 808 nm traditional pumping are compared. Higher slope efficiency of 34% and maximum output power of 16.5 W are obtained for the 885nm pump with a 6ram length 1 at.% Nd:YAG ceramic. The advantages for 885nm direct pumping are discussed in detail. This pumping scheme for highly doping a Nd:YAG ceramic laser is considered as an available way to generate high power and good beam quality simultaneously. 相似文献
917.
Hawking radiation as tunneling and the unified first law of thermodynamics at the apparent horizon of the FRW universe
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Relations between the tunneling rate FRW universe are investigated. The namics in such a dynamical system. first law of thermodynamics through and the unified first law of thermodynamics at the apparent horizon of the tunneling rate arises as a consequence of the unified first law of thermodyAnalysis shows how the tunneling is intimately connected with the unified the principle of conservation of energy. 相似文献
918.
Crystal Structure and Magnetic Properties of Sm2 Fe17-Nδ Thin Films Deposited on Si (100) Substrates
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This work focuses on the crystal structure and magnetic properties of the hard magnetic Sm2 Fe17 Nδ films prepared by dc magnetron sputtering and the subsequent nitriding process. The XRD, EDS, M-H and M-T data show that N enters the cell structure and the films with the single Th2Zn17 phase are obtained when the nitriding temperature varies from 300 to 400℃, thus the maximum value of the coercivity Hc reaches 2561.7Oe. However, the Sm2Fo17 phase decomposes to the StuN nonmagnetic phase and the α-Fe soft magnetic phase with further increasing nitriding temperature, which corresponds to the decreasing Hc. Furthermore, the easy magnetization direction (EMD) is found to locate randomly in the film plane. This texture can not give an excellent MR/Ms higher than the Stoner-Wohlfarth limitation (MR/Ms = 0.5), which agrees well with the observed low MR/Ms (0.58). It is suggested that the magnetization reversal process is dominated by the nucleation mechanism according to the initial magnetization curve and the dependence of Hc on the field H. 相似文献
919.
Photoluminescence and X-Ray Photoelectron Spectroscopy of p-Type Phosphorus-Doped ZnO Films Prepared by MOCVD
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Reproducible p-type phosphorus-doped ZnO (p-ZnO:P) films are prepared on semi-insulating InP substrates by metal-organic chemical vapour deposition technology. The electrical properties of these films show a hole concentration of 9.02 × 10^17 cm ^-3, a mobifity of 1.05 cm^2 /Vs, and a resistivity of 6.6 Ω.cm. Obvious acceptorbound-exciton-related emission and P-induced zinc vacancy (Vzn) emission are observed by low-temperature photoluminescence spectra of the films, and the acceptor binding energy is estimated to be about 125meV. The local chemical bonding environments of the phosphorus atoms in the ZnO are also identified by x-ray photoelectron spectra. Our results show direct experimental evidence that Pzn-2Vzn shallow acceptor complex most likely contributes to the p-type conductivity of ZnO:P films. 相似文献
920.
A single-mode photonic crystal waveguide with a linear tapered slot is presented, which can localize light spatially by changing the slot width. Its effective bandwidth is 52nm, from 1500nm to 1552nm. Along the tapered structure, the slot width is reduced, and the corresponding band curve shifts. The group velocity of light becomes zero at the band edge. Therefore, different frequency components of the guided light are slowed down and finally localized at correspondingly different widths inside a tapered slot photonic crystal waveguide. Furthermore, this structure can confine light wave in a narrow slot waveguide, which may effectively enhance the interaction between light and the low-index wave-guiding materials filled in the slot. 相似文献