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131.
132.
A. Doicu T. Trautmann 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(17):1851-1863
Several methods for solving the radiative transfer equation in a spherical atmosphere are presented. These methods include the long characteristic Picard iteration, and the conventional and the accelerated short characteristic Picard iteration. Approximate methods as for instance the Picard iteration methods with open boundaries are also discussed. The analysis is focussed on the computational efficiency and accuracy of the proposed method and their applicability to atmospheric remote sensing. 相似文献
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Jae-Ho Kim 《Journal of fluorine chemistry》2006,127(8):1054-1057
LiMF6 (M = Ta, Nb) was prepared by the reaction between LiF and MF5 (M = Ta, Nb) in F2 gas. Pure LiMF6 (M = Ta, Nb) salts were obtained by using the reaction at temperatures higher than 473 K under 80 kPa (F2) for 24 h. The x values in LiMFx (M = Ta, Nb) were confirmed as 5.7-6.0 by XRD-Rietveld analysis. Results showed that LiMF6 (M = Ta, Nb) has a trigonal structure (, Z = 3). The respective lattice parameters of LiTaF6 and LiNbF6 are a0 = 0.533 nm, c0 = 1.362 and a0 = 0.532 nm, c0 = 1.360. The equivalent conductivities of both LiMF6 (M = Ta, Nb) in propylene carbonate (PC) are equal at 15.2 Ω−1 cm2 mol−1 at 0.01 mol dm−3. The electrochemical potential window of TaF6− is 7.0 V, which is 0.4 and 0.2 V wider, respectively, than those of BF4− and PF6−. 相似文献
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制备了基于聚(3-己基噻吩)(P3HT)与可溶性富勒烯衍生物(PCBM)共混体系的太阳能电池。通过改变活性层退火处理时惰性气氛环境的压强,在一定程度上实现对共混物相分离以及聚合物结晶度的控制,研究了LiF作为阴极缓冲层对不同压强下退火处理的器件性能的影响。实验发现,LiF层的关键作用在于稳定开路电压以及提升短路电流,从而带动转化效率整体提升。结果表明,LiF层可以改善器件活性层与金属电极接触的界面形态,而器件的最终性能则由活性层的微观形貌与电极界面形态共同决定。 相似文献
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为了解决环境光和显示器色温对LCD显示器图像颜色再现有较大影响的问题,提出一种基于LCD显示器光谱特性的图像颜色一致性方法。通过测量在不同环境光和色温下99个行业认可颜色的光谱,总结出不同环境光和色温对LCD显示器图像颜色再现的光谱规律。利用不同环境光下的光谱叠加性及不同色温下的光谱对应规律,实现了不同环境光和色温下的LCD显示器图像颜色一致性,一致性后的图像平均主观评价Z得分为0.50。研究结果表明,该方法能够很好地解决不同环境光和色温下的LCD显示器图像颜色的一致性问题。 相似文献
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Microwave plasma torch mass spectrometry for the direct detection of copper and molybdenum ions in aqueous liquids 下载免费PDF全文
Xiaohong Xiong Tao Jiang Runzhi Zhou Shangxian Wang Wei Zou Zhiqiang Zhu 《Journal of mass spectrometry : JMS》2016,51(5):369-377
Microwave plasma torch (MPT) is a simple and low power‐consumption ambient ion source. And the MPT Mass spectra of many metal elements usually exhibit some novel features different from their inductively coupled plasma (ICP) mass spectra, which may be helpful for metal element analysis. Here, we presented the results about the MPT mass spectra of copper and molybdenum elements by a linear ion trap mass spectrometer (LTQ). The generated copper or molybdenum contained ions in plasma were characterized further in collision‐induced dissociated (CID) experiments. These researches built a novel, direct and sensitive method for the direct analysis of trace levels of copper and molybdenum in aqueous liquids. Quantitative results showed that the limit of detection (LOD) by using MS2 procedure was estimated to be 0.265 µg/l (ppb) for copper and 0.497 µg/l for molybdenum. The linear dynamics ranges cover at least 2 orders of magnitude and the analysis of a single aqueous sample can be completed in 5–6 min with a reasonable semi‐quantitative sense. Two practical aqueous samples, milk and urine, were also analyzed qualitatively with reasonable recovery rates and RSD. These experimental data demonstrated that the MPT MS is able to turn into a promising and hopeful tool in field analysis of copper and molybdenum ions in water and some aqueous media, and can be applied in many fields, such as environmental controlling, hydrogeology, and water quality inspection. Moreover, MPT MS could also be used as the supplement of ICP‐MS for the rapid and in‐situ analysis of metal ions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献