Angle-dependent infrared absorption spectroscopy at electrode/electrolyte interfaces

Angle-dependent internal reflection spectroscopy is performed in the attenuated total reflection setup for an electrochemical cell with a Fourier transform infrared spectrometer. The working electrode is a thin Pt film evaporated onto a hemispherical Si prism. The refractive index of the Pt film obtained from the experiment is found to differ from the value for bulk material. The difference is ascribed to the surface corrugation of the Pt surface and the film thickness in the nanometer range. The function of reflection intensity versus angle of incidence changes significantly when a resonant absorption occurs in the electrolyte medium. The angle-dependent absorption band intensity of CO adsorbed on the Pt film under potential control reveals changes in magnitude and an inversion of the band for different angles of incidence. This behaviour is explained by the excitation of resonant surface plasmon waves at the Pt/electrolyte interface and by multiple reflections occurring at the interfaces. A simulation for the three-layer system Si/Pt/electrolyte agrees with the experimental results.     

Adsorption and decomposition of NO on K-deposited Pd(1 1 1)

The adsorption and decomposition of NO on a K-deposited Pd(1 1 1) surface were investigated using X-ray photoelectron spectroscopy, infrared reflection absorption spectroscopy, and temperature-programmed desorption. For the K-deposited Pd(1 1 1) surface, two different NO adsorption sites were observed in addition to the Pd site. On the clean Pd(1 1 1) surface, the adsorption of NO was purely molecular and reversible, but on the K-deposited surface, the adsorbed NO decomposed at two different temperatures, 530 and 610 K. These results indicate that the NO adsorption and decomposition sites were newly created by the deposition of K onto the Pd(1 1 1) surface.     

火焰原子吸收法测定硅酸盐中铁钙镁

研究火焰原子吸收法测定硅基体中铁、钙、镁时，硅对待测元素吸收信号的干扰及表面活性剂对硅干扰的抑制作用。以十六烷基吡啶盐（ＣＰＣ）作干扰抑制剂，ＦＡＡＳ法测定硅酸盐中铁、钙、镁等元素，灵敏、简便、无干扰。合成样品中铁、钙、镁的回收率分别为９９．８％、１０１．３％和９８．３％。     

Study of absorption spectra of gasolines and other hydrocarbon mixtures in the second overtone region of the CH<Subscript>3</Subscript>, CH<Subscript>2</Subscript>, CH groups

We have obtained experimental and model absorption spectra for individual hydrocarbons (toluene, benzene, n-heptane, and iso-octane) and their mixtures in the near IR range (λ = 1080–1220 nm). We model the spectra of nonsynthetic gasolines obtained under the same conditions by combining the spectra of three pure hydrocarbons. We show that the octane number of the studied gasoline is linearly related to the toluene (or benzene) concentrations in the model mixture. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 2, pp. 157–161, March–April, 2007.     

间接原子吸收光谱法测定氢溴酸山莨菪碱

研究了原子吸收光谱法间接测定氢溴酸山莨菪碱。在溶液pH为 5 1～ 5 3,当四苯硼钠过量时可完全沉淀氢溴酸山莨菪碱 ;加入过量的氯化钾沉淀滤液中剩余的四苯硼钠 ;干过滤 ,用原子吸收分光光度计在76 6 5nm波长下测定滤液中过量的钾 ,因四苯硼钠与氢溴酸山莨菪碱和氯化钾均按 1∶1的计量关系生成沉淀 ,可以直接计算得到氢溴酸山莨菪碱的含量。对氢溴酸山莨菪碱注射液进行了测定 ,测定结果准确。方法简单快速 ,回收率在 96 %～ 10 3%之间 ,相对标准偏差为 1 4 %。该方法可进一步推广原子吸收光谱法在其他相关药物测定方面的应用。     

火焰原子吸收分析中表面活性剂的增感和抑制干扰作用的机理研究

证实和补充了文献［１］建立的ＦＡＡＳ分析中表面活性剂的增感机理模型，并对ＦＡＡＳ分析中表面活性剂抑制共存元素干扰的作用和机理作了探讨。表面活性剂能抑制共存元素干扰的主要原因是其胶团能和被测元素的离子或干扰离子形成胶团化物；表面活性剂在火焰中中的不完全燃烧使火焰气体还原性增强，温度升高也是其抑制干扰的因素之一。     

The dielectric properties of dry and water-saturated nylon-12

The dielectric relaxation of 30% crystalline Nylon-12 of molecular weight 20,000 has been studied at frequencies from 12 Hz to 0.1 MHz and temperatures from 77 to 375 K, and the effect of water on the relaxation spectra has been investigated. Absorbed water increases both the rate and the intensity of both its α-and β-relaxation processes and increases the rate but decreases the intensity of its γ-relaxation process. These results are interpreted in terms of the hydrogen bonding effects of water on localized motions of dipoles in Nylon-12. The relatively large half-width of the α-relaxation, which becomes better resolved at high temperatures, is attributed mainly to the random distribution of crystalline regions in the polymer. It is suggested that water lowers the steric hindrance for the localized mode of dipolar reorientation and causes a redistribution of local sites such that the β-relaxation process grows at the expense of the γ-process.     

BaFCl_（x）Br_（1－x）：Sm~（2＋）中_（5）D_2→~（7）F_

本文以ＢａＦＣｌｘＢｒ－１－ｘ：Ｓｍ２＋Ｄ２→７Ｆ０的跃迁几率随ｘ变化为中心对ＢａＦＣｌｘＢｒ－１－ｘ：Ｓｍ２＋体系４ｆ５ｄ带的激发光谱、５Ｄ２→７Ｆ０跃迁的荧光衰减随温度的变化特性、５Ｄ２→７Ｆ０的跃迁几率等进行了研究．从而得出结论：在ＢａＦＣｌｘＢｒ１－ｘ：Ｓｍ２＋中，随Ｂｒ含量的增大，４ｆ５ｄ带与５Ｄ２能级更加接近，使７Ｆ０→Ｄ２的吸收截面增大，从而可能提高在５Ｄ２：能级烧孔的效率．     

电热原子吸收光谱法中原子形成机理的热力学和动力学研究

本文对电热原子吸收光谱法（ＥＴＡＡＳ）中气态原子形成机理的热力学和动力学研究状况进行了评述，引用文献６２篇。     

从薄膜波导传播衰减的角度研究光学薄膜的损耗:(Ⅱ)实验分析

本文从实验的角度介绍从薄膜导波传播衰减研究光学薄膜损耗的方法,并以一些低损耗的光学薄膜样品的测量结果说明这种方法对损耗研究的灵敏程度及其优越性.