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具有径向导电面的多层介质圆波导的传播特性
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作者 熊天信 杨儒贵 《信息与电子工程》 2004年第2期102-105,共4页
采用分离变量的方法,推出了具有径向导电面、多层普通介质填充的圆柱波导各层电磁场之间的递推关系,得到了其模式场解,并进一步推出了此波导的本征方程。将其应用于只有一种介质填充情况,结果和有关文献相同。作为示例,文中给出了填充... 采用分离变量的方法,推出了具有径向导电面、多层普通介质填充的圆柱波导各层电磁场之间的递推关系,得到了其模式场解,并进一步推出了此波导的本征方程。将其应用于只有一种介质填充情况,结果和有关文献相同。作为示例,文中给出了填充两层介质时,一些模式的色散特性的计算结果。 展开更多
关键词 电子技术 传播特性 分离交量法 本征方程 圆波导 多层介质 径向导电面
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STUDY ON THE DETERMINATION OF TRACE BISMUTH(III) BY THIN-LAYER RESIN PHASE SPECTROPHOTOMETRY
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作者 YAN Yongsheng LUXiaohua FU Chengguang 《Chinese Journal of Reactive Polymers》 2003年第1期50-58,共9页
In this paper, a new thin-layer ion-exchange resin phase analytical method is introduced. It is based on that, the bismuthous cation can associate with iodic anions, so as to formed an anion complex [BiI4-] in a stron... In this paper, a new thin-layer ion-exchange resin phase analytical method is introduced. It is based on that, the bismuthous cation can associate with iodic anions, so as to formed an anion complex [BiI4-] in a strong acidic environments. This anion complex can also exchanges with a weaker anions on the surface active site of anion exchange resin, so that a [R+] [BiI4-] solid phase binary associational system is produced. Owing to the solid system is a great many dispersive particulates, it can be pressed to a thin-layer by press tools of the so called 搕hin-layer resin phase?or 搑esin phase? and using this solid association system spectrophotometry for the determination of trace metals. So it can increase the analytical sensitivity. This association system exhibits maximum absorbance at 460nm, and obeys Beer抯 law over the concentration range 0.01ug/ml^1.20ug/ml of bismuthous(III). It has a molar absorptivity of 7.1×105 [L/mol穋m]. It indicated the resin phase spectrophotometry is a sensitive analytical method for trace bismuthous. It is 18 times higher than routine aqueous spectrophotometry. The relative standard deviations is 1.82% (n=6) for the measurements of 0.5ug/ml Bi(III). The detection limit of Bismuthous(III) is 1.4×10-8mol/L. The method has applied to the analysis Bi(III) in environmental water samples. 展开更多
关键词 Thin-layer phase Spectrophotometry Trace bismuth (III) DETERMINATION
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