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1.
利用UV Vis吸收光谱仪和光化学反应器研究了含二茂铁基偶氮染料及相应的偶氮染料溶液的光降解动力学 .在溶液中 ,它们的光降解反应遵循零级动力学模型 .与相应的偶氮染料相比 ,含二茂铁基的偶氮染料溶液具有较好的光稳定性 .这表明 ,在其分子内存在着有效的从偶氮染料母体到二茂铁基团的分子内三重态 三重态能量传递 ,上述过程降低了偶氮染料激发三重态的生成 ,避免了染料的过早降解 ,提高了其稳定性  相似文献   

2.
吡啶酮系偶氮染料腙体结构中,亚胺基质子能与水分子中的质子发生交换和解离.用核磁双共振实验测定了交换速率(k_A)和活化能(E_0)两者均与染料结构、pH值、温度、溶剂性质和水含量等因素有关.在重氮和偶合组分上的亲电取代基和溶液中的碱都能促进交换反应.本文进一步解释了该系列染料的变色机理和染料具有不同的pH值.  相似文献   

3.
由1-氨基蒽醌和不同偶合基合成了九个含蒽醌基的单偶氮染料,并对其进行了 元素分析、红外光谱和紫外光谱表征。紫外光谱研究结果表明,偶合基酰胺芳环上 取代基对偶氮染料的吸收光谱影响不大。当偶合基由2-羟基-3-氨替酰胺萘酚( Azol~8)变为2-羟基-11氢-苯并咔唑-3-氨替酰胺萘酚(Azo9)时,偶氮染料的吸收 红移了130 nm,最大吸收出现在662 nm处,成为近红外染料。偶氮染料光电导性质 的研究表,偶合基酰胺芳环上取代基吸电子效应越强,光敏性越好,且与Hammett 常数σ有良好的相关性。值得注意的是萘环上扩大一个咔唑环(Azo9),使偶氮染 料的光敏性提高了几十倍,表明在萘环上扩大共轭环是提高偶氮染料光敏性的一个 良好途径。  相似文献   

4.
张玉红  赵华绒  俞庆森 《化学学报》2002,60(8):1513-1516
由1-氨基蒽醌和不同偶合基合成了九个含蒽醌基的单偶氮染料,并对其进行了 元素分析、红外光谱和紫外光谱表征。紫外光谱研究结果表明,偶合基酰胺芳环上 取代基对偶氮染料的吸收光谱影响不大。当偶合基由2-羟基-3-氨替酰胺萘酚( Azol~8)变为2-羟基-11氢-苯并咔唑-3-氨替酰胺萘酚(Azo9)时,偶氮染料的吸收 红移了130 nm,最大吸收出现在662 nm处,成为近红外染料。偶氮染料光电导性质 的研究表,偶合基酰胺芳环上取代基吸电子效应越强,光敏性越好,且与Hammett 常数σ有良好的相关性。值得注意的是萘环上扩大一个咔唑环(Azo9),使偶氮染 料的光敏性提高了几十倍,表明在萘环上扩大共轭环是提高偶氮染料光敏性的一个 良好途径。  相似文献   

5.
彭勤纪  刘辉  李慕洁 《化学学报》1995,53(12):1215-1220
吡啶酮系偶氮染料腙体结构中, 亚胺基质子能与水分子中的质子发生交换和解离。用核磁双共振实验测定了交换速率(ka)和活化能(E0)。两者均与染料结构、pH值、温度、溶剂性质和水含量等因素有关。在重氮和偶合组分一的亲电取代基和溶液中的碱都能促进交换反应。本文进一步解释了该系列染料的变色机理和染料具有不同的pH值。  相似文献   

6.
蓝光有机存储染料研究进展   总被引:1,自引:0,他引:1  
近年来,蓝光有机存储染料作为超高密度存储技术的核心已经日益受到人们的广泛关注,出现了与之相关的大量专利文献报道.本文介绍了卟啉染料、偶氮染料、菁染料、芪类染料和香豆素衍生物染料等蓝光染料的合成及应用,并对蓝光有机存储染料的发展趋势作了展望.  相似文献   

7.
合成并表征了5种不对称五甲川菁染料,染料在甲醇中的最大吸收和荧光光谱在646—666nm之间.光降解实验证明两端取代基结构呈不对称的染料,其光稳定性明显高于两端取代基结构对称的染料.染料荧光光谱和pH值的关系表明,染料中引入苯环取代基可以增强染料在酸性或碱性溶液中的稳定性.  相似文献   

8.
近红外荧光染料探针因其信噪比高、组织穿透力强、对生物样品光损伤小等优势,在生物荧光成像领域备受瞩目.主族元素取代的罗丹明染料探针,不仅具有生物样品适用的近红外光谱性质,同时还保留了传统罗丹明的诸多优点,其中以硅原子取代的罗丹明分子中的氧原子而形成的硅基罗丹明染料探针最为突出.基于其优越的近红外光化学性质,硅基罗丹明染料探针已经广泛应用于生物样品的荧光识别成像.主族元素取代的罗丹明近红外荧光染料探针的发展,丰富了荧光染料探针的种类和数量,拓展了荧光染料探针的应用.本文综述了近年来主族元素取代的罗丹明染料的发展,主要探讨了探针的设计思路、荧光信号调控机制及其近红外成像应用.  相似文献   

9.
偶氮化合物可用作非线性光学材料、激光盘信息存贮材料和现代科技中的油溶性染料[1].传统偶氮化合物的制备有重氮盐偶合和取代肼氧化等许多方法[2~4],其偶氮基两端一般联有烃基或芳环,而联有羰基的偶氮类化合物用通常方法难以制备.本文首次用N-溴代丁二酰亚...  相似文献   

10.
以硅磁粒子(Fe_3O_4@SiO_2)为核,采用低温-原位氧化聚合-共沉淀法制备了多层核壳聚苯胺硅磁复合物(Fe_3O_4@SiO_2@PANI).通过X射线衍射分析(XRD)、傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等对Fe_3O_4@SiO2_@PANI复合物的结构、形貌和性质进行了表征.以磺酸基偶氮染料甲基橙、刚果红和蒽醌染料茜素红溶液模拟染料废水,对其在Fe_3O_4@SiO_2@PANI上的吸附进行了研究,讨论了pH值、吸附时间、染料初始浓度及吸附剂用量对吸附过程的影响,优化了吸附条件.实验结果表明,弱酸性(p H6. 0)条件下,Fe_3O_4@SiO_2@PANI对甲基橙、刚果红和茜素红具有优异的选择性吸附性能,其平衡吸附量分别为26. 05,34. 0和69. 58 mg/g.该复合物对染料的吸附过程更接近Langmuir等温吸附的单分子层吸附机理,其对染料废水的去除率高达96. 5%,易于分离,且重复使用性能良好.  相似文献   

11.
Two new azo dyes of alpha-isoxazolylazo-beta-diketones and their Ni(II) and Cu(II) complexes with blue-violet light wavelength were synthesized using a coupling component, different diazo components and metal (II) ions (Ni2+ and Cu2+). Based on the elemental analysis, MS spectra and FT-IR spectral analyses, azo dyes were unequivocally shown to exist as hydrazoketo and azoenol forms which were respectively obtained from the solution forms and from the solid forms. The action of sodium methoxide (NaOMe) on azo dyes in solutions converts hydrazoketo form into azoenol form, so azo dyes are coordinated with metal (II) ions as co-ligands in the azoenol forms. The solubility of all the compounds in common organic solvents such as 2,2,3,3-tetrafluoro-1-propanol (TFP) or chloroform (CHCl3) and absorption properties of spin-coating thin films were measured. The difference of absorption maxima from the complexes to their ligands was discussed. In addition, the TG analysis of the complexes was also determined, and their thermal stability was evaluated. It is found that these new metal (II) complexes had potential application for high-density digital versatile disc-recordable (HD-DVD-R) system due to their good solubility in organic solvents, reasonable and controllable absorption spectra in blue-violet light region and high thermal stability.  相似文献   

12.
Y. L. Wang  J. Y. Wang  J. P. Li  D. L. Ma 《合成通讯》2013,43(19):3579-3582
Phase transfer catalyzed dehydrogenation synthesis azo Ureas Compounds have been studied. Ten of the compounds were Synthesized by the reaction of aryl Substituted Semicarbazied Compounds with phase transfer catalyst–“Galvinoxyl” radical between two phase under mild Conditions. The products are obtained in 90–99(%) yield. Their structure are identified by elemental analysis, IR, 1HNMR, MS spectra. A possible mechanism is suggested by a “Galvinoxyl” radical act on aryl substituted semicarbazide formed azo compounds.

Synthesis of bis (Substituted phenyl) Carbodiazone Compounds (ArN = NCON = NAr') have been reported1, As another part of our studies, 1, 4-di-Substituted azo Compounds (ArNHCON=NAr') Were Synthesized by the reaction of Substituted Semicarbazide Compounds With a phase transfer Catalyst-“Galvinoxyl” radical, which has been acted as a radical Scavenger2, yet, “Galvinoxyl” radical used as phase transfer Catalyst have not been reported so far. Azo Compounds have been widely utilized as dyes and analytical reagents. They can also be used as material of non - linear optics, optic information storring material in Laser dish and dyes with oil solubility in photochromy in modern technology3,4. Recently, many noteworthy Studies show that azobenzene derivative Possess Very good optic remembering and photoelectric properties5, optical Switching and Image storege by means of Azobenzene Liquid - Crystal Films6. The preparation of the azo compounds which have the Connection of -N = N- and hydrocarbyl group have been described in many Literatures7,8.. In this paper, a new reaction of phase transfer Catalyzed dehydrogenation of aryl Substituted Semicarbazide  相似文献   

13.
简述了偶氮染料的检测现状,对偶氮染料研究中表面增强拉曼光谱检测方法进行了综述。介绍了表面增强拉曼光谱用金属溶胶、金属电极、金属薄膜3种增强基底在偶氮染料检测中的方向,并对其在偶氮染料检测中的研究前景进行了展望。表面增强拉曼光谱法是一种新型光谱分析技术,具有操作简单、快速、灵敏度高等优势,为偶氮染料的检测开辟了新道路。  相似文献   

14.
Three groups of dyes were synthesized and characterized in order to examine their solubility, absorption spectrum, and order parameter in liquid crystal hosts. Our synthesis method allowed the formation of the diazonium salts and the diazo coupling in ethyl acetate instead of an aqueous medium, permitting the formation of long and neutral azo dyes. In the liquid crystal BDH-E7, they showed order parameters in the range of 0.52 to 0.76. The two dyes with the longest molecular lengths were particularly interesting due to their very broad absorption spectra in the visible region. Each of these two compounds behave as single component black dye guest/host systems, which generally require a mixture of two or three dyes in the liquid crystal host. These dyes were also evaluated for use in polymer dispersed liquid crystal films.  相似文献   

15.
Abstract

Three groups of dyes were synthesized and characterized in order to examine their solubility, absorption spectrum, and order parameter in liquid crystal hosts. Our synthesis method allowed the formation of the diazonium salts and the diazo coupling in ethyl acetate instead of an aqueous medium, permitting the formation of long and neutral azo dyes. In the liquid crystal BDH-E7, they showed order parameters in the range of 0.52 to 0.76. The two dyes with the longest molecular lengths were particularly interesting due to their very broad absorption spectra in the visible region. Each of these two compounds behave as single component black dye guest/host systems, which generally require a mixture of two or three dyes in the liquid crystal host. These dyes were also evaluated for use in polymer dispersed liquid crystal films.  相似文献   

16.
Recent advances in azo dye degrading enzyme research   总被引:1,自引:0,他引:1  
Azo dyes, which are characterized by one or more azo bonds, are a predominant class of colorants used in tattooing, cosmetics, foods, and consumer products. These dyes are mainly metabolized by bacteria to colorless aromatic amines, some of which are carcinogenic, by azoreductases that catalyze a NAD(P)H-dependent reduction. The resulting amines are further degraded aerobically by bacteria. Some bacteria have the ability to degrade azo dyes both aerobically and anaerobically. Plant-degrading white rot fungi can break down azo dyes by utilizing a number of oxidases and peroxidases as well. In yeast, a ferric reductase system participates in the extracellular reduction of azo dyes. Recently, two types of azoreductases have been discovered in bacteria. The first class of azoreductases is monomeric flavin-free enzymes containing a putative NAD(P)H binding motif at their N-termini; the second class is polymeric flavin dependent enzymes which are studied more extensively. Azoreductases from bacteria represent novel families of enzymes with little similarity to other reductases. Dissociation and reconstitution of the flavin dependent azoreductases demonstrate that the non-covalent bound flavin prosthetic group is required for the enzymatic functions. In this review, structures and carcinogenicity of azo colorants, protein structure, enzymatic function, and substrate specificity, as well as application of the azo dyes and azoreductases will be discussed.  相似文献   

17.
LDH/Tris/Pd (CaAl‐layered double hydroxide/tris (hydroxymethyl)aminomethane/palladium) was synthesized and appraised for its catalytic activity towards the degradation of two selected azo dyes. The decolorization of azo dyes, acid red 18 (AR 18) and reactive yellow 15 (RY 15), requires considerably small amounts of synthesized catalyst. Kinetic studies show that the catalytic decolorization of these azo dyes follows the first order kinetic model. The reported method is simple and applicable; in addition, the stable catalyst can efficiently decolorize model azo dyes with good recyclability. Therefore, LDH/Tris/Pd can be accepted as the possible component for the utilization in wastewater treatment.  相似文献   

18.
Several primary amines are known to be endogenous substances, and they are to be detected at very low concentration level. Novel water-soluble azo dyes as precolumn derivatizing reagents were synthesized for the analysis of primary amines with strong visible-light absorption by CZE. A coupling reaction was used to introduce a sulfophenylazo group to salicylaldehyde or 1-hydroxy-2-naphthaldehyde to extend the conjugation and to improve the solubility in water of the derivatizing reagents, as well as the target compounds of the reaction products with the primary amines. Two azo dyes of 5-(4-sulfophenylazo)salicylaldehyde sodium salt (AZO1) and 4-(4-sulfophenylazo)-1-hydroxy-2-naphthaldehyde sodium salt (AZO2) were synthesized. Separation of eight kinds of n-alkylamines was performed by CZE after the derivatization with AZO1 or AZO2. The addition of Brij 35 to the running electrolyte and to the sample solutions was necessary to improve the solubility and the resolution among the analytes. Both reagents, AZO1 and AZO2, were compared with each other in terms of the reaction time of derivatization, the detection sensitivity and the total analysis time. The derivatization process using AZO2 was applied to the determination of four biogenic amines, histamine, tyramine, cadaverine and putrescine, and LODs at around micromolar level were achieved for the four amines.  相似文献   

19.
A string of novel heterocyclic mono azo dyes were synthesized and their utilization in dyeing different fabrics as wool and nylon were discussed. Thienopyridine azo dyes 4 and 6 were prepared by reaction of chloro acetamidederivative 2 with diamino compounds to yield 3 and 5 , followed by reaction with NaNO2/HCl and coupling with nucleophilic reagent. One-pot reaction of chloro acetamide 2 with ammonium thiocyanat in solvent ethanol gave the unexpected thienopyrimidine derivative 7 , which contain two active sites, the former is primary amine that was able to form diazonium salt that coupled with N,N-dimethylaniline, resorcinol, and/or self-coupling to afford the azo dyes 8-10 , and the latter is active methylene group that underwent coupling with different diazonium salts to give the azo thienopyrimidine derivative dye 11-15 . The dyeing performance of these azo dyes had been investigated in terms of their dyeing behavior and fastness properties on different fabrics. Results showed that the color strength (K/S) values, as well as, washing, rubbing, and resistance to acid, alkali and light showed high efficiency of these heterocyclic mono azo dyes to dye wool rather than nylon fibers.  相似文献   

20.
Geotrichum sp. strain, which is able to decolorize azo dyes enzymatically, was used in this study for decolorization of synthetics solutions contaminated by toxic azo dyes orange G, trypan blue, azorubine, and methyl red. The biomass of Geotrichum sp. was immobilized in calcium alginate and polyacrylamide gels and used for the decolorization of tested azo dyes in fluidized bed bioreactor. The highest specific decolorization rate was obtained when the fungal biomass was entrapped in calcium alginate beads. Immobilized biomass in calcium alginate continuously decolorized azo dyes after eight repeated batch decolorization experiments without significant loss of activity whereas polyacrylamide immobilized biomass retained only 10% of its activity after 4 days of incubation. The effects of some physicochemical parameters such as temperature, pH, and dyes concentration on decolorization performance of isolated fungal strain were also investigated.  相似文献   

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