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41.
介绍了在极紫外波段,利用帽层材料来减少多层膜反射镜因外部环境干扰而造成的反射率降低,使多层膜光学元件能够长时间稳定工作.计算了在139nm波长处Mo/Si极紫外多层膜反射镜在表面镀制不同帽层材料时的理论最大反射率,利用单纯形调优法,对帽层和多层膜的周期厚度进行优化,同时把分层理论用于多层膜帽层优化,可使多层膜的反射率得到进一步提高.分析了在加入帽层前后多层膜外层电场强度的分布变化情况.
关键词:
多层膜
反射率
帽层
极紫外 相似文献
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Yao HC Wang JJ Ma YS Waldmann O Du WX Song Y Li YZ Zheng LM Decurtins S Xin XQ 《Chemical communications (Cambridge, England)》2006,(16):1745-1747
This communication reports the first example of cyclic ferric clusters with an odd number of iron atoms capped by phosphonate ligands, namely, [Fe9(mu-OH)(7)(mu-O)2(O3PC6H9)8(py)12]. The magnetic studies support a S = 1/2 ground state with an exchange coupling constant of about J approximately equal to -30 K. 相似文献
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Jer-Shien Chen San-Liang Lee Hong-Chang Kung Hen-Wai Tsao 《Optical and Quantum Electronics》2009,41(11-13):859-871
We propose a numerical model, including modulation transform function and self-sustained pulsation condition, to estimate the self-sustained pulsation frequency, matched to the measured pulsation frequency, which considers the structure factors in a two-section distributed feedback laser with a thin shift-layer. 相似文献
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Mixed micelles of polyethylene glycol (23) lauryl ether with ionic surfactants studied by proton 1D and 2D NMR 总被引:2,自引:0,他引:2
Gao HC Zhao S Mao SZ Yuan HZ Yu JY Shen LF Du YR 《Journal of colloid and interface science》2002,249(1):200-208
(1)H NMR chemical shift, spin-lattice relaxation time, spin-spin relaxation time, self-diffusion coefficient, and two-dimensional nuclear Overhauser enhancement (2D NOESY) measurements have been used to study the nonionic-ionic surfactant mixed micelles. Cetyl trimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) were used as the ionic surfactants and polyethylene glycol (23) lauryl ether (Brij-35) as the nonionic surfactant. The two systems are both with varying molar ratios of CTAB/Brij-35 (C/B) and SDS/Brij-35 (S/B) ranging from 0.5 to 2, respectively, at a constant concentration of 6 mM for Brij-35 in aqueous solutions. Results give information about the relative arrangement of the surfactant molecules in the mixed micelles. In the former system, the trimethyl groups attached to the polar heads of the CTAB molecules are located between the first oxy-ethylene groups next to the hydrophobic chains of Brij-35 molecules. These oxy-ethylene groups gradually move outward from the hydrophobic core of the mixed micelle with an increase in C/B in the mixed solution. In contrast to the case of the CTAB/Triton X-100 system, the long flexible hydrophilic poly oxy-ethylene chains, which are in the exterior part of the mixed micelles, remain coiled, but looser, surrounding the hydrophobic core. There is almost no variation in conformation of the hydrophilic chains of Brij-35 molecules in the mixed micelles of the SDS/Brij-35 system as the S/B increases. The hydrophobic chains of both CTAB and SDS are co-aggregated with Brij-35, respectively, in their mixed micellar cores. 相似文献
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Nanosized alumina powders were prepared from Al(NO3)3·9H2O and (NH4)2CO3 through the synthesis of ammonium aluminium carbonate hydroxide (AACH) and followed by calcination. TG-DTA, XRD, TEM and BET were employed to study the process of AACH thermal decomposition and to characterize the products obtained. The results show that high purity (99.97%) and nanosized spherical α-Al2O3 powders with the diameter of 40~50nm and BET surface area 32.5m2·g-1 can be obtained by calcining AACH at 1150℃ for 1.5h, the sequence of phase transformation during calcination was AACH → amorphous Al2O3 → γ-Al2O3 → α-Al2O3, and the activation energy of AACH decomposition is (115±5)kJ·mol-1. 相似文献
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