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含碲唑杂环部花青的合成 总被引:2,自引:0,他引:2
含碲唑杂环部花青的合成罗学红,刘秀芳,徐汉生(武汉大学化学系,430072)部花青(又称份菁,merocyanines)是一类重要的功能染料。它不仅可以作为感蓝或感绿的光谱增感剂应用于照相化学领域 ̄[1],也可作为光盘染料用于其它信息记录 ̄[2]。这... 相似文献
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在卤化银乳剂中加人一种染料,能赋予乳剂对染料所吸收的光谱部分以感光性。这种染料称为光谱增感染料。光谱增感剂尤如卤化银乳剂的眼睛,使它能看到五彩七色。即能使卤化银乳剂的感光范围从蓝紫光区扩展到绿、红、甚至红外光区。可制得感应蓝紫光、绿光的正色片,感应全部可见光的全色片,以及能感应红外光的红外片。 相似文献
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菁是一种具有多功能用途的染料,除用作卤化银感光材料及有机光导材料的光谱增感剂、光记录材料中记录介质外,还可作为染料激光器中用的激光染料.我们曾合成了四甲川苯乙烯菁、五甲川(艹粦)及五甲川吡喃鎓等红外染料作为激光染料,测定了它们的光性能.本文合成了具有桥链的七甲川菁,研究了这些桥链七甲川菁的吸收光谱及荧光光谱,并以YAG激光倍频(532nm)作泵浦源,测定了它们的激光调谐范围、中心波长及激光转换效率. 相似文献
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荧光染料吖啶红作测定蛋白质的生物探针——蛋白质的染料分析法新进展 总被引:17,自引:0,他引:17
简述染料结合分析法的发展过程,吖啶红染料自取和体系测定蛋白质的最佳试验条件和测定结果。阳离子荧光染料吖淀红及其自聚的二聚体的可平衡转化,形成自聚平衡体系,在表面活性剂十二烷基磺酸钠的存在下,蛋白质的定量加入可调节这一平衡,从而引起体系 荧光有规律的变化。方法线性范围宽、灵敏度高、反应速度快、准确度高 、抗干扰 能力强,是染料分析法定量测定蛋白质的最新方法之一。 相似文献
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近红外激光防护染料 总被引:13,自引:0,他引:13
以激光防护和隐身材料为需求背景,概述了菁类染料(含多次甲基菁染料、方酸菁和克酮酸菁染料、薁染料)、酞菁类染料(含普通酞菁和萘酞菁)、金属络合物染料、醌型染料、偶氮染料、游离基型染料、芳甲烷型染料、苝类染料等近红外吸?
杖玖系难芯孔纯黾敖埂?
$601$ADuetotherequirementofnear-infraredlaserprotectivedyesandlaserstealthmaterials,thisreviewfocusedontheresearchprogressofnear-infraredabsorbingdyes,andsomesuggestionswereputforwardonthefutureresearch.Someofthemostimportanttechnicalrequiremnetsforlaser-protectivedyeswithintheplasticareasfollows:sharpabsorptionbandsatspecificwavelengthscorrespondingtolaseremission,excellentlightfastness,robustthermalandchemicalstability,stabilitytoambientconditions,highopticaldensityandscotopicluminoustransmission,goodsolubilityinplasticandlowtoxicity.Thisreviewpaidattentiontothepropertiessuchasthemaximumabsorptionwavelengthandtheabsorptionintense,attentionhadbeendirectedtowardseighttypesnear-infrareddyes:cyaninedyeswhichincludedpolymethinedyesandsquaryliumorcroconiumdyes,phthalocyaninesandnaphthalocyanines,metalcomplexdyes,quinonedyes,azodyes,radicaldyes,multiphenylmethanedyesandperylenedyes.Otherkindsofnear-infrareddyeswerealsomentioned,suchasaromaticannulenes,planescontainignso-callednonbenzenoidaromaticrings,cycliccross-conjugatedhydrocarbonshavinginsertedp-quiniodring,fluorenyliumdyeswithinorganicanions,donor-acceptorcyclophanes,tetrapyrazinoporphyrazinesandpentaazadentateexpandedporphyrinsetal.Allofthedyesmentionedabovehadsomegoodpropertiesforuseasthenear-infraredlaserprotectivedyesandlaserstealthmaterials,buttherealsoexisteddefectsineverykindofdyes. 相似文献
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荧烷染料和二芳基碘Weng盐组成的体系,在光作用下,通过激发态的荧烷染料与碘Weng之间发生电子转移反应,生成开环结构的荧烷染料有色体,伴随发生Weng盐的光解反应,生成活性引发自由基碎片。该体系不仅可有效地引发烯类单体的聚合反应,也可同步发生光生色作用,产生较高的色密度。 相似文献
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合成了6种五甲川吡喃Weng盐染料,通过红外光谱,核磁共振氢谱及元素分析确证了其结构。研究了其电子吸收光谱及其在Nd^3+:YAG激光器上的锁模性能。结果表明,染料在1,2-二氯溶液里最大吸波波长在1052-1095nm之间,6个染料全部锁模成功,脉宽为28-35ps,锁模情况比镍络硫代双烯型染料BDN好。 相似文献
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Recent advances in azo dye degrading enzyme research 总被引:1,自引:0,他引:1
Chen H 《Current protein & peptide science》2006,7(2):101-111
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
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Jan Saska Zheng Li Andrew L. Otsuki Jiahui Wei James C. Fettinger Mark Mascal 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17453-17456
The dye and pigment manufacturing industry is one of the most polluting in the world. Each year, over one million tons of petrochemical colorants are produced globally, the synthesis of which generates a large amount of waste. Naturally occurring, plant‐based dyes, on the other hand, are resource intensive to produce (land, water, energy), and are generally less effective as colorants. Between these two extremes would be synthetic dyes that are fully sourced from biomass‐derived intermediates. The present work describes the synthesis of such compounds, containing strong chromophores that lead to bright colors in the yellow to red region of the visible spectrum. The study was originally motivated by an early report of an unidentified halomethylfurfural derivative which resulted from hydrolysis in the presence of barium carbonate, now characterized as a butenolide of 5‐(hydroxymethyl)furfural (HMF). The method has been generalized for the synthesis of dyes from other biobased platform molecules, and a mechanism is proposed. 相似文献
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Riin Rebane Ivo LeitoSergei Yurchenko Koit Herodes 《Journal of chromatography. A》2010,1217(17):2747-2757
Sudan dyes are a family of lipophilic azo dyes, extensively used in industrial and scientific applications but banned for use as food colorants due to their carcinogenicity. Due to the continuing illicit use of Sudan dyes as food colorants their determination in different food matrices – especially in different chilli and tomato sauces and related products – has during the recent years received increasing attention all over the world. This paper critically reviews the published determination methods of Sudan I–IV dyes. LC–UV–vis and LC–MS are the dominating methods for analysis of Sudan I–IV dyes. Sudan dyes are usually found in food at mg kg−1 levels at which it may be necessary to use a preconcentration step in order to attain the desired detection limits. Liquid–solid extraction is the dominating sample preparation procedure. In recent years it has been supplemented by ultrasonic-assisted extraction and pressurized liquid extraction. Various solid phase extraction types have been used for sample cleanup. The large majority of works use conventional C18 columns and conventional LC eluents. Traditionally the UV–vis absorbance detection has been the most frequently used. In the recent years MS detection is applied more and more often as it offers more reliable identification possibilities. 相似文献
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Wang San-Lang Yu Hao-Ting Tsai Min-Hsiung Doan Chien Thang Nguyen Van Bon Do Van Chung Nguyen Anh Dzung 《Research on Chemical Intermediates》2018,44(8):4903-4911
Research on Chemical Intermediates - The purpose of this study was to reclaim squid pens for the production of chitosanases and biosorbents of food colorants and industrial dyes via Bacillus cereus... 相似文献
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An accurate method was developed for the simultaneous determination of water-Tartrazine, Amaranth, Ponceau 4R, Sunset Yellow FCF, and fat-Sudan (I-IV), synthetic soluble colorants in foodstuff. This method uses dimethylsulfoxide (DMSO) as the extraction solvent in the sample preparation process and high performance liquid chromatography (HPLC)-diode array detector (DAD)-electrospray mass spectrometry (ESI-MS), applying selected ion recording in positive/negative alternate mode to acquire mass spectral data, as the analytical technique. Linearity of around three orders in the magnitude of concentration was generally obtained. Detection and quantification limits of the investigated dyes, which were evaluated at signal to noise ratio of 3 for detection limit and 10 for quantification limit, were in the ranges of 0.01-4 and 0.03-11.2 ng, respectively. The recoveries of the eight synthetic colorants in four matrices ranged from 93.2 to 108.3%. Relative standard deviations of less than 8.2% were also achieved. This method has been applied successfully in the determination of water-soluble colorants in the soft drink and the delicious ginger, and fat-soluble dyes in chilli powders and chilli spices. 相似文献
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Characterization of natural organic colorants in historical and art objects by high‐performance liquid chromatography
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High‐performance liquid chromatography plays an important role in analysis of historical organic colorants. A number of papers have been published in this field over the last 30 years. Classification of the most commonly used natural dyes and an overview of high‐performance liquid chromatography methods with main focus on recent works (2008 to the beginning of 2014) are provided. The review deals with an entire analytical protocol covering sample preparation, chromatographic separation, and suitable detection (UV/visible and fluorescent spectroscopy and mass spectrometric techniques). High‐performance liquid chromatography has been successfully used in the complete characterization of some organic dyestuffs present in historical and art objects. The possibilities and difficulties for identification of natural sources of historical colorants are also discussed. 相似文献
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A study for the determination of the aromatic amines formed after reduction of the azo colorants mostly used in toys was conducted. Sodium dithionite was used in the reductive cleavage of the azo group for the dyes, and the released amines were subsequently analysed by high-performance liquid chromatography with UV detection. The influence of different variables related to the reduction process was investigated by the use of a full-level factorial design, where most significant parameters as well as order interactions were studied. Reduction profiles for each colorant were obtained by studying the changes in the amount of amine obtained with different dithionite/colorant ratios. The expected aromatic amines forming azo colorants were detected, and in the presence of a nitro group a further reduction was observed. The yield of the total reduction process was determined by using standard addition of different quantities of amines to the colorants. 相似文献