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1.
考察了染料3-磺丙乙基-5',5-二苯基-9-乙基-恶碳菁(1)和染料3-羟乙基-3'-磺丙基-5-甲氧基-5'-氯-9-乙基-噻碳菁在五种明胶溶液中的发光光谱。发现染料聚集态的形成受不同类型明胶的影响,也与染料本身结构有关。  相似文献   

2.
余沛侠  张丽惠 《感光材料》1998,(3):29-31,48
通过地含有不同阴离子的3,3′,9-三乙基-4,5,4′,5′-二苯并硫碳菁染料的乳剂试验,研究了染料阴离子对感光度,染料的聚集态,增感峰和增感范围,染料吸附等温线和电子顺磁共振(ESR)信号的影响。  相似文献   

3.
在反胶束体系中研究了菁染料的吸收光谱以及ω值对菁染料荧光光谱的影响.讨论了不同粒径的AgCl纳米粒子对反胶束体系中菁染料的吸附状态及J-聚集体形成的影响.特别研究了反胶束水团空间限定效应对菁染料荧光量子产率及J-聚集体的影响。  相似文献   

4.
用半导体精密量热计测得25±0.01℃时溴化银从DMF-H_2O溶液中吸附噻碳菁染料(Ⅰ)的吸附热。发现由于溶液中染料聚集状态的不同导致吸附热明显不同,但吸附于溴化银表面的染料的聚集态则基本相  相似文献   

5.
本文研究了5-位不同取代基的噻碳菁和吲哚碳菁染料对其在立方型颗粒和T-颗粒溴化银微晶上吸附能力的影响,并采用ACFEM(AnalyticalColorFluorescenceElectronMicroscopy)研究了上述结构染料对其吸附在溴化银微晶所形成的J-聚集体尺寸分布的影响.实验结果表明,对吲哚碳菁染料来说,立方体溴化银微晶表面的吸附能力较T-颗粒溴化银微晶表面的吸附能力强;但对噻碳菁染料来说则相反,它们在T-颗粒溴化银微晶表面的吸附能力较立方体溴化银微晶表面的吸附能力强.另外,对5-位不同取代基的噻碳菁染料而言,无论是在立方型颗粒或T-颗粒溴化银微晶上的吸附能力来说,含取代基(无论4-取代基是吸电子型还是推电子型)的噻碳菁染料较未取代的噻碳菁染料强;而5-位取代基是吸电子型的噻碳菁染料更有利于其吸附在T-颗粒溴化银微晶表面.此外,本文还进一步证明了溴化银微晶表面上染料J-聚集体的生长过程是符合奥斯瓦尔特成熟过程的.吲哚碳菁染料在T-颗粒溴化银微晶上形成的J-聚集体的平均尺寸明显大于在立方体溴化银微晶上形成的J-聚集体的平均尺寸.吸附在立方体溴化银微晶上的5-不同取代基的噻碳菁染料对其形成J-聚集体  相似文献   

6.
报道了具有相同发色团,并有不同电荷的二种菁染料单分子膜中J-聚集体的形成。测定了单分子膜的π/A,△V/A曲线,反射光谱及吸收光谱。从实验结果得出:带正电荷的染料与花生酸混合形成单分子膜后,膜中染料的二聚体与J-聚集体随着表面压力改变存在着一个平衡。而带负电荷的染料与二十烷基胺成膜后,即使在很低的表面压下也有J-聚集体形成。同时染料分子在水面上的取向是各向异性。  相似文献   

7.
设计、合成了3种水溶性吲哚菁染料(发射波长:690 nm),用核磁共振波谱(NMR)对其进行了表征,测试了菁染料在不同溶剂中的紫外吸收光谱和荧光发射光谱;为了探讨菁染料在生物分析领域的应用性,测定3种菁染料在十六烷基三甲基溴化铵(CTAB)和十二烷基磺酸钠(SDS)两种表面活性剂胶束模拟的生理条件下的吸收和发射光谱,利用循环伏安法(CV)测定了菁染料的光稳定性,在近红外区域观察了染料对肾癌细胞的活细胞染色性能,并计算了3种菁染料的摩尔吸光系数和荧光量子产率。  相似文献   

8.
本文研究了5-位不同取代基的噻碳菁和吲哚碳菁染料对其在立方型颗粒和T-颗粒溴化银微晶上吸附能力的影响,并采用ACFEM(AnalyticalColorFluorescenceElectronMicroscopy)研究了上述结构染料对其吸附在溴化银微晶所形成的J-聚集体尺寸分布的影响,实验结果表明,对吲哚碳菁染料来说,立方体溴化银微晶表面的吸附能力较T-颗粒溴化银微晶表面的吸附能力强,但对噻碳菁染料  相似文献   

9.
由吸收光谱研究了3,3′-二(丁-磺酸丙基)-9-乙基-4,5,4′,5′-二苯并噻碳菁三乙胺盐(Ⅰ)在DMF-水溶液中生成J-聚集体的效应;直接测量了25℃形成J-聚集体过程的热效应,得到了J-聚集体的聚集热△Hs=—(43±1)×10~3J(表示1摩尔单分子染料连接到J-聚集体上的平均焓变化)。根据Daltrozzo等人将J-聚集体生成当作“结晶”过程的观点,求得该体系中染料I J-聚集体至少包含的染料单分子数n为6。  相似文献   

10.
《腐植酸》2015,(6)
<正>利用菁染料超分子作分子探针对黄腐酸进行标记,检测黄腐酸和药效机制对生命科学和药物化学领域的发展具有重要意义。采用紫外-可见吸收光谱和圆二色谱研究黄腐酸为模板对不同结构菁染料超分子的组装及手性调控。结果表明:黄腐酸能诱导3种菁染料J-聚集体解聚为单体并  相似文献   

11.
A spectroscopic study (UV–vis and adsorption) has been made of the interactions of select model azo dyes with a range of surfactant types or their mixtures both above and below their respective critical micelle concentrations. All surfactants inhibit adsorption of the dyes to cotton above their critical micelle concentrations due to incorporation in micelles. However, formation of 1;1 complexes between dyes and cationic or zwitterionic surfactants in sub‐micellar regions results in enhanced deposition on cotton. It is shown that attractive or repulsive electrostatic interactions play a key role in dye binding to micelles. Unusually, spectra of complexes formed between the dye and cationic surfactant are typical of those of the azo tautomeric form as opposed to the hydrazone form that is prevalent in aqueous media. Addition of anionic surfactant to micellar solutions of nonionic or zwitterionic surfactants results in successive displacement of dye from the respective micelles, i.e. binding is competitive.  相似文献   

12.
《分离科学与技术》2012,47(11):2582-2597
Abstract

Benzene, toluene, ethylbenzene, and xylene are frequently observed contaminants in industrial wastewaters causing concerns about environmental and health effects. An aqueous surfactant two-phase (ASTP) extraction system using mixtures of cationic and anionic surfactants have been shown to be a promising surfactant-based separation technique to concentrate solutes such as proteins and dyes from aqueous solution. A phase separation of a surfactant solution occurs at certain surfactant compositions and concentrations, forming two isotropic phases. One is rich in surfactant aggregates (surfactant-rich phase) and the other is lean in surfactant aggregates (surfactant-dilute phase). Most of the organic contaminants tend to solubilize and concentrate in the surfactant-rich phase, leaving the surfactant-dilute phase containing only small amounts of contaminants as remediated water. The effect of NaCl addition on the critical micelle concentration (CMC) and the extraction ability of ASTP formed by mixtures of cationic surfactant (dodecyltrimethylammonium bromide; DTAB) and anionic surfactant (alkyl diphenyloxide disulfonate; DPDS) at 50 mM total surfactant concentration with a 2:1 molar ratio of DTAB:DPDS was investigated; the CMC of the mixture slightly decreases with increasing NaCl concentration. The extraction and preconcentration of benzene are greatly enhanced by added NaCl. The higher the degree of hydrophobicity of contaminants, the greater the extraction into the surfactant-rich phases. At 1.0 M NaCl addition, about 95% of xylene, 92% of ethylbenzene, 90% of toluene, and 79% of benzene are extracted into the surfactant-rich phase within a single stage extraction and the contaminant partition ratios can be as high as 395 for xylene, 273 for ethylbenzene, 206 for toluene, and 84 for benzene, which are greater than those obtained from the conventional ASTP extraction system using nonionic surfactants.  相似文献   

13.
A wide-ranging investigation has been made of the adsorption of direct dyes to cotton and of inhibition by surfactants, polymers and polymer–surfactant mixtures. Generally, the selected polymers are extremely effective at inhibiting adsorption of most of the direct dyes to cotton but are less effective at inhibiting adsorption of small, model azo dyes. Micellar solutions of zwitterionic and cationic surfactants can inhibit adsorption of both small dyes and commercial dyes. It is shown that anionic surfactants at sub-micellar concentrations can inhibit polymer-dye interactions due to displacement of dye and/or relocation into micelle-like polymer–surfactant complexes. New insights have been obtained into the interactions of dyes with cotton and with polymers, surfactants or their mixtures, particularly into observed dye selectivities.  相似文献   

14.
本文利用皮秒时间分辨条纹相机技术检测了3种染料在立方颗粒溴化银上吸附后形成聚集体的荧光光谱,分析了3种染料在不同染料浓度下对染料聚集体到溴化银导带的超快电子转移过程的影响,进而分析其对增感效率的影响关系,并探讨了增感过程的微观机理.实验结果表明,荧光衰减的动力学曲线与一个双指数函数拟合得相当好,存在一快一慢两个衰减成分,快衰减成分占拟合较大比例,表明其源于与荧光衰减相竞争的从激发态染料聚集体到AgBr导带的电子转移.光致电子转移的速率及增感效率随着染料相对浓度的增加表现出一定的变化趋势,染料浓度增加,增感效率减小.  相似文献   

15.
增感染料与卤化银微晶之间的作用及其聚集态的研究   总被引:1,自引:0,他引:1  
本文研究了光谱增感染料的结构对立方体卤化银乳剂的感光性能的影响,并利用反射光谱和彩色分析荧光电镜研究了染料在卤化银微晶上的聚集态和J-聚集体的相对尺寸,通过测定乳剂离子电导率研究了染料的结构对乳剂离子电导率的影响。  相似文献   

16.
综述了gemini(双子)表面活性剂的分子结构以及溶液的浓度、温度、pH值和反离子等因素对gemini表面活性剂聚集行为的影响。通过调整以上因素可以有目的地调控gemini表面活性剂有序聚集体的形成。这些有序聚集体不仅在生产和生活中有重要应用,而且与生命活动中的一系列现象密切相关,受到各个领域科学家的广泛重视。尽管gemini表面活性剂所形成的各种聚集体已经得到了广泛证实,但对形成的机理和实际应用的研究仍比较薄弱。  相似文献   

17.
Nonionic surfactants are widely used in reactive dyeing processes, and the interaction between surfactants and reactive dyes affect the hydrolytic property of reactive dyes. In this study, reactive brilliant blue KN‐R (C.I. reactive blue 19) was employed as a model dye, and fatty alcohol polyoxyethylene ether (AEO‐9) was selected as a model nonionic surfactant. The interaction was first investigated in aqueous solutions by a UV‐spectrophotometry method, then the effect of surfactant concentration on the hydrolytic behavior of KN‐R was studied using high performance liquid chromatography method. Below the critical micelle concentration, the surfactant served as dispersant; the hydrolysis of reactive dye was accelerated. However, when the concentration of surfactant was above its critical micelle concentration, the dye was solubilized into the micellar phase, which was revealed from the changes in absorbance intensity and wavelength of the maximum absorbance. This led to slowed hydrolysis of reactive dye. These findings are useful in understanding the effect of concentration of nonionic surfactant on the hydrolysis of vinyl sulfone reactive dyes.  相似文献   

18.
An ultraviolet-visible spectroscopic investigation has been made of the interactions of a specially synthesised series of substituted, model arylazonaphthol dyes with nonionic and anionic surfactants. Changes in spectral features were recorded above the critical micelle concentrations, suggesting specific interactions of dyes with micelles of the respective surfactants. The affinity of the dye for the surfactant micelles increased when various p -substituent were incorporated in to the dyes. Similarly, there was a shift in azo–hydrazone tautomeric equilibria and an increase in measured dye p K a values. Models are proposed for the location of dyes in nonionic or anionic micelles. Unlike earlier studies, it is concluded that the solubilised dye experiences only one environment in nonionic micelles but the specific location, i.e. whether preferentially incorporated in the hydrophobic micellar interior or in the more hydrophilic, outer polyoxyethylene layer, depends upon the nature of the substituent.  相似文献   

19.
The interaction of two Indian natural dyes, namely madder (Rubia cordifolia) and mallow (Punica granatum), with cationic surfactant cetyl trimethyl ammonium bromide and anionic surfactant sodium lauryl sulphate, has been studied. Spectrophotometric data showed a strong interaction between the natural dyes and the surfactants. The critical micelle concentration of the surfactants, determined by measurement of specific conductance and surface tension, was found to decrease on the addition of natural dyes in an aqueous solution of surfactants. The thermodynamic and surface parameters for the interaction have been evaluated.  相似文献   

20.
Our present research describes the surface properties of three biobased anionic surfactant synthesized from vinylguaiacol and 11-bromo undecanoic acid. To further improve its hydrophobicity and bioavailability, amino acid head group incorporation was carried out. All these synthesized compounds were thoroughly characterized using NMR and mass spectroscopy. The performance properties such as foaming, wetting, emulsification value and calcium tolerance were evaluated. The studied surfactants possess excellent emulsion stability and moderate calcium tolerance as compared to commercially available surfactant sodium lauryl sulfate (SLS). The micelle formation and the thermodynamics involved at the air–water interface were estimated from surface tension measurements. These surfactants showed a higher tendency towards adsorption at the air–water interface than micellization. Dynamic light scattering and steady state fluorescence anisotropy study were carried out to shed light on the bulk micellization properties of the synthesized surfactant. Along with spherical micelles of <5 nm size, larger aggregates (35–84 nm) were observed with higher anisotropy values. FESEM images further confirmed the larger spherical micelles formed by these surfactants. The surfactants formed chiral aggregates above the critical micelle concentration as indicated by circular dichroism spectra. These surfactants may be suitable candidates for additives to detergents to improve their calcium tolerance especially in the case of hard water. Furthermore, a low foaming ability along with high emulsion stability may find these surfactants to be better replacement of the conventional surfactant used as emulsifiers in many industrial applications.  相似文献   

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