有机银溶胶的吸收光谱和表面增强Raman光谱研究

研究了2-氨基苯并咪唑(BIMNH₂)、LiCl、NaOEt对Ag/EtOH溶胶吸收光谱和表面增强Raman散射(SERS)光谱的影响。结果表明,少量的吸附分子BIMNH₂、LiCl、NaOEt均能改变溶胶聚集状态,从而影响其吸收光谱和SERS效应。此外,Cl^-还可与Ag、BIMNH₂形成表面络合物而增强SERS效应。对Ag溶胶体系SERS光谱的溶剂效应也作了初步研究。     

pH-Dependent Surface-Enhanced Raman Scattering of 8-Hydroxy Quinoline Adsorbed on Silver Hydrosol

Surface-enhanced Raman scattering (SERS) of 8-hydroxy quinoline (HQ) adsorbed on silver hydrosols are compared with the FTIR and normal Raman spectrum in the bulk and in solution. Definite evidence of the charge transfer interaction to the overall contribution in the SER enhancement has been reported. The excitation profile study also supports the evidence of a charge transfer interaction. The effect of pH variation on the SER band intensity is explained in terms of chemisorption of the molecule on bare and chlorinated silver surfaces. The apparent enhancement factor calculations of the principal Raman bands indicate that in the surface-adsorbed state, an HQ molecule is oriented neither flat nor vertical to the silver surface but is tilted. Copyright 2000 Academic Press.     

二十二碳六烯酸乙酯及其与银离子络合物的紫外光谱

报道了二十二碳六烯酸DHA之酯－银离子络合物的生成条件,和DHA人酯及其与银离子络合物的紫外光谱特性,总结了络合前后光谱特征峰的移动规律,揭示了该络合物的结构和络合反应机理。     

Polarized Low-Temperature Crystal Spectra of Inorganic Complexes

The electronic spectra of complexes are especially informative if they are recorded for crystals at low temperature or at varying temperature with polarized light. This straightforward technique frequently permits reliable band assignment. Such assignments, being independent of the assumptions of any particular theoretical model, then provide a basis for testing theories of electronic structure.     

银溶胶体系表面增强拉曼散射光谱的溶剂效应

研究了银溶胶体系表面增强拉曼散射光谱的溶剂效应,发现在不同的溶剂中,银溶胶的聚集状态不同,当胶粒带电荷时,溶剂还能影响分子在胶粒表面的吸附,溶剂通过改变胶粒的聚集状态及分子在胶粒上的吸附这两个因素影响银溶胶体系的SERS光谱。     

Electronic Absorption Spectra and Tautomerism of Quinizarin and Its Substituted Derivatives

According to the data of quantum-chemical calculations and correlation analysis, the experimental electronic absorption spectra of quinizarin and its substituted derivatives contain bands corresponding to 9,10-, 1,10-, and 1,4-anthraquinoid tautomers. Analysis of the absorption spectra revealed specific features of the tautomeric structure of substituted quinizarins.     

溶剂中微量水对取代酞菁锌吸收光谱的影响

测定了6种烷氧基取代酞菁锌在不同溶剂中的电子吸收光谱. 在一些溶剂(如甲苯、氯仿和二氯甲烷)中, 除了存在典型的Q带吸收峰外, 在其长波长一侧还可观测到一个新的吸收峰, 结合对其荧光、核磁共振谱、添加强碱性溶剂(吡啶)以及对溶剂除水后的光谱的研究, 证实了新产生的吸收峰与溶剂中的微量水有关, 探讨了该吸收峰产生的原因.     

给电子基团对吲哚染料电子结构和吸收光谱的影响

利用密度泛函理论(DFT)和含时密度泛函理论(TD-DFT), 分别基于B3LYP和PBE1PBE方法研究了一系列含有不同给电子基团的吲哚染料分子(ID1-ID3)的电子结构和吸收光谱性质. 重点比较了不同电子给体对染料的分子结构、吸收光谱以及其在电池中的光伏性能的影响. 结果表明从ID1、ID2到ID3, 随着电子给体中苯环数目的增加, 吲哚分子上的共轭效应逐渐增大, 导致吲哚分子最高占据分子轨道-最低未占据分子轨道(HOMO-LUMO)之间的能隙变窄, 分子的吸收光谱发生红移. 染料分子的吸收光谱和LUMO能级分别影响染料的吸光效率和光电转化过程中电子的注入过程, 从而使其二者成为决定电池光伏性能的重要参数. 综合考虑上述两个参数对电池性能的贡献, 通过理论研究证实, 在ID1-ID3系列染料中, ID3具有较长的吸收谱带、较大的分子消光系数和合适的LUMO能级, 从而表现出最为优越的光伏性能, 这与实验得出的结论很好地吻合.     

The Effect of a Constant Electric Field on the Absorption Spectra of Polymethine Dyes

The intensities of the long wavelength absorption bands of symmetrical and unsymmetrical polycarbocyanines in polymer films are redistributed in a constant electric field. This redistribution depends in a regular manner on the chemical structure of the dyes. The spectroscopic effects are interpreted via a change in the probability of the vibronic transitions caused by redistribution of the electron density in the chromophore of the dye in the external electric field.     

Electronic Absorption Spectra of Substituted Phenols

The spectral properties of o-aminophenol, catechol, o-nitrophenol, pyrogallol, salicylic acid and gallic acid were investigated in different solvents. The behaviour of hydrogen bonding demonstrated in these systems was discussed.     

Absorption Spectra of Sodium Aluminate Solutions

The absorption spectra of sodium aluminate solutions have been examined at different concentrations. As a result, it was found that the characteristic absorption band due to aluminate ion shows a λ_max at 265–270 mm?.     

Structure and Absorption Spectra of Polyhydroquinones

Radical polymerization of hydroquinone was studied in an aqueous medium. Black polymers of low molecular weight (up to 1500 Da), poorly soluble in water and alcohols, are formed. Ab initio calculations of the steric and electronic structure and vibrational and electronic spectra of molecules containing 1 to 5 hydroquinone units were performed.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 4, 2005, pp. 662–668.Original Russian Text Copyright © 2005 by Zagorskii, Kalnin’sh, Toropov.     

细胞色素C的光谱研究

细胞色素C是吸呼链的1个重要组成部分,位于细胞色素C₁和细胞色素a之间,血红素辅基中的铁原子可交替地处于+3或+2氧化态^[1]。Smith^[2]和Osheroff等^[3]对细胞色素C与细胞色素C₁及a的结合进行了详细的研究。关于细胞色素C与小分子的相互作用,除Corthesy^[4]进行了与ATP的作用,Osheroff^[3]进行了与碳酸根的作用外,与其它小分子的作用以及氧化型、还原型之间的相互转化受介质的影响还未见报道。     

绿色银纳米粒子的共振散射光谱研究

以柠檬酸钠作光还原剂,采用紫外光-可见光二步光化学法制备了绿色银纳米离子,在399.4nm和691.5nm处有二个紫外-可见吸收峰;在340nm,470nm和520nm处有三个共振散射峰,从超分子和纳米粒子这一整体出发,探讨了共振散射光谱产生的原因及银超分子光反应机理。     

盐酸丁卡因-赤藓红反应体系的吸收光谱及分析应用

建立一种测定盐酸丁卡因的分光光度新方法。 在pH=4.0的Britton-Robinson（BR）缓冲溶液中,盐酸丁卡因（TC·HCl）与赤藓红（ET）形成1∶1的离子缔合物,导致溶液的吸收光谱变化,除在516 nm处产生明显的褪色作用外,并在558 nm处出现增色现象。 TC·HCl在0.1×10^-6~7.2×10^-6 g/mL范围内其质量浓度与褪色波长和增色波长处的吸光度变化值均呈良好的线性关系。 褪色法和增色法的摩尔吸光系数（ε）分别为3.30×10⁴和2.22×10⁴ L/(mol·cm)。 当用双波长叠加法时,ε值为5.52×10⁴ L/(mol·cm)。 研究了适宜的反应条件和分析化学性质,并结合量子化学AM1法讨论了反应机理。 方法用于人血清及尿样中盐酸丁卡因的含量测定,回收率在98.1%~103.3％之间。     

低温焙烧-原子吸收法测定高含量辉锑矿中的金

采用先低温焙烧除硫后再高温焙烧,通过王水溶样,对辉锑矿矿样焙烧方法的对比表明,利用方法焙烧样品,矿样不结块,金可溶解完全.方法经国家一级标准物质分析验证,结果与标准值相符.对实际样品测定的方法精密度为1.44%～4.79%(RSD,n=5).加标回收率在95.5%～104.3%,方法快速、准确,适用于高含量辉锑矿中金的批量样品分析.     

Au纳米粒子表面附近偶氮苯分子的吸收光谱

我们将时空间含时密度泛函理论与经典的电动力学时空间有限差分技术相结合,对吸附在Au纳米粒子表面附近的偶氮苯分子顺式和反式两种同分异构体的光学性质进行了研究。计算结果显示,一方面表面等离子激元共振会增大其周围激光外场的强度,从而使得偶氮苯分子的吸收光谱得到增强,另一方面,吸附分子与金属纳米粒子之间的相互耦合作用也会对一些低能特殊谱峰的强度及位置产生影响,从而使得谱线的形状与单独的偶氮苯分子或Au纳米粒子并不相同。此外,等离子激元的增强效应会随着分子与金属纳米粒子之间的距离以及纳米粒子尺寸的变化而发生变化。     

溶质和溶剂极性对二氮杂苯异构体吸收光谱移动的影响

采用根据连续介质理论和热力学约束平衡态方法得到的新非平衡态静电溶剂化能公式, 在单球孔穴点偶极模型近似下推导得到了吸收/发射光谱移动计算的新解析公式. 在CASSCF(6,5)/6-31＋＋G**水平上分别计算了邻位、间位、对位三种二氮杂苯异构体真空中的 跃迁吸收光谱能量值和在5种不同极性溶剂中的偶极矩, 并讨论了三种异构体偶极矩变化和溶剂极性变化对 跃迁的吸收光谱移动的影响.     

痕量银的液膜富集与原子吸收法测定

研究了分离与富集痕量银的液条件,摸索出一种新的液膜体系ＴＯＡＮ２０５煤油０－ＮＨ３．Ｈ２Ｏ,提出了最佳富集条件。经５次提取分离,富集倍数可达８２倍。回收率在９８％以上。与火焰原子回收法相结合可测ｎｇ／ｍｌ级的Ａｇ＾＋此法用于富集地质标样中的痕量银,相对标准偏差为２．４％（ｎ＝１０）     

Absorption Spectra Calculation of Torus-type C_(120) and Its Nitrogen Doped Derivatives

The absorption spectra of torus-type C_(120) and its derivatives doped by nitrogen(C_(119)N, C_(118)N_2, C_(115)N_5) have been investigated based on the density functional theory. The longest absorption band of torus-type C_(120) can arrive at the near IR fields. For three derivatives doped by nitrogen, doped nitrogen atoms can induce the longer absorption band, and the more numbers of nitrogen atoms are doped in torus-type C_(120), the longer absorption band can be induced.