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101.
Ga1-xInxAs(x>0.53)材料是未来长距离低损耗光纤通信的理想光源材料和探测器材料之一.我们采用水平常压MOCVD系统,在InP衬底上成功地生长了Ga1-xInxAs(x>0.53)/InAsyP1-y/Inp异质结材料.其中InAs1-yPy为组份阶梯变化的多层结构.由样品的(400)面X光衍射结果测定了各层组份.由二次离子质谱(SIMS)得到了样品剖面组份变化结果,证明InAs1-yPy层组份为阶梯状变化的.通过对光致发光结果和X光衍射结果比较,可以看到,InAsyP1-y层通过位错和弹性畸变二种方式来释放或积累Ga1-xInxAs与InP间的失配应力,从而减少了Ga1-xInxAs中的失配位错.有效地改善了Ga1-xInxAs的质量.已获得了x高达0.94表面光亮的Ga1-xInxAs/InAs1-yPy/InP异质结材料. 相似文献
102.
单扫描示波极谱测定痕量银 总被引:1,自引:0,他引:1
本文首次提出了运用单扫描极谱直接测定银的方法。在含N-烯丙基-N′-对苯磺酸钠硫脲及四乙烯五胺的硼砂缓冲液中,银离子在-0.66V(相对饱和甘汞电极)有一灵敏还原波。运用经典极谱或单扫描极谱,此波均可用于微量银的定量测定。“银波”的单扫描示波极谱波可在5×10~(-7)~3×10~(-5)mol/L范围内检测银。方法已用于废定影液中银含量的分析,结果满意。 相似文献
103.
104.
PARAMETER ESTIMATION OF SPATIAL AR MODEL 总被引:1,自引:0,他引:1
Jiang Jiming 《数学年刊B辑(英文版)》1991,12(4):432-444
Consider a stable AR model of two parameter spatial series {X_t, t∈N~2}, i. e. {X_(t)t∈N~2} is homogeneous and satisfies the following difference equationX_t-sum from n=s∈相似文献
105.
106.
After taking into account energy conservation and the particle’s self-gravitation interaction, Hawking radiation of the massive
particle as tunneling from Schwarzshild-anti-de Sitter black hole is studied by using Parikh-Wilczek’s semi-classical quantum
tunneling approach. Meanwhile, Hawking radiation as tunneling from the black hole is reexamined by developing Angheben–Nadalini–Vanzo–Zerbini
(ANVZ) covariant method to cover energy conservation and the particle’s self-gravitation interaction. Both the results perfectly
generalize those obtained by Parikh and Wilczek, and show that the tunneling rate is related to the change of Bekenstein-Hawking
entropy, and the factual emission spectrum is not exactly thermal, but satisfies the underlying unitary theory.
PACS: 04.70-s, 9760. Lf. 相似文献
107.
We examine the problem of building or fortifying a network to defend against enemy attacks in various scenarios. In particular,
we examine the case in which an enemy can destroy any portion of any arc that a designer constructs on the network, subject
to some interdiction budget. This problem takes the form of a three-level, two-player game, in which the designer acts first
to construct a network and transmit an initial set of flows through the network. The enemy acts next to destroy a set of constructed
arcs in the designer’s network, and the designer acts last to transmit a final set of flows in the network. Most studies of
this nature assume that the enemy will act optimally; however, in real-world scenarios one cannot necessarily assume rationality
on the part of the enemy. Hence, we prescribe optimal network design algorithms for three different profiles of enemy action:
an enemy destroying arcs based on capacities, based on initial flows, or acting optimally to minimize our maximum profits
obtained from transmitting flows. 相似文献
108.
J. S. Yang Z. G. Chen Y. T. Hu S. N. Jiang S. H. Guo 《Archive of Applied Mechanics (Ingenieur Archiv)》2007,77(10):689-696
We study thickness-twist vibrations and waves in an unbounded, multi-sectioned piezoelectric plate of crystals with 6 mm symmetry
or polarized ceramics. An exact solution from the three-dimensional equations of piezoelectricity is obtained. Basic vibration
and wave propagation characteristics are calculated based on the solution. The results are useful in the understanding and
design of plate resonators, filters and acoustic wave sensors of ZnO, AlN and polarized ceramics. 相似文献
109.
The purpose of the present note is to establish some new delay integral inequalities, which provide explicit bounds on unknown functions and generalize some results of Li et al. [Some new delay integral inequalities and their applications, J. Comput. Appl. Math. 180 (2005) 191–200]. The inequalities given here can be used to investigate the qualitative properties of certain delay differential equations and delay integral equations. 相似文献
110.
Qin Jiang 《Journal of Mathematical Analysis and Applications》2007,328(1):380-389
Some solvability conditions of periodic and subharmonic solutions are obtained for a class of subquadratic nonautonomous second-order Hamiltonian systems by the minimax methods in critical point theory. 相似文献