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1.
在染料敏化太阳电池中,染料敏化剂分成无机染料与有机染料两大类。无机染料受稀有金属钌的制约而成本较高,开发有机染料是降低染料敏化太阳电池成本的有效手段,成为目前研究的热点。本文从有机染料敏化剂的分子设计入手,简述了染料敏化太阳电池中有机染料敏化剂的基本结构,将有机染料敏化剂分为吲哚啉类染料、香豆素类染料、三苯胺类染料、菁...  相似文献   

2.
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   

3.
染发已成为人们的日常需要与时尚选择。目前广泛使用的化学染发剂主要成分为对苯二胺类物质,其引起的致敏性、致癌性与致突变性等问题日益凸显。生物质染发剂及仿生染发剂与化学合成染发剂相比具有安全低毒、资源可再生、环境友好等优点。本文以近年来国内外对绿色安全染发剂的研究为基础,从头发的组成结构和显色机理出发,从生物质染发剂以及仿生染发剂两个方面总结了绿色安全染发剂的研究现状与发展瓶颈,并对其应用前景进行了展望,旨在为安全无毒、绿色健康染发剂的研发提供参考。  相似文献   

4.
Polymer particles containing oil-soluble dyes (colored latex particles) were prepared by mini-emulsion polymerization. Copper phthalocyanine dyes and styryl dyes were used as oil-soluble dyes. Highly hydrophobic dyes played the role of hydrophobe by themselves and enabled the full incorporation of dyes in the latex without additional hydrophobes. Two phthalocyanine dyes having similar color were blended in a mini-emulsion polymerization so that the resulting colored latex showed enough strong color depth as a colorant. Colored latexes with high dye content (more than 30 wt% for phthalocyanine dye system and 40 wt% for styryl one) and with particle size less than 100 nm were obtained.  相似文献   

5.
6.
Dyes with high affinity for polylactide   总被引:3,自引:0,他引:3  
Attempts were made to develop dyes with high affinity for polylactide as an alternative to the existent commercial disperse dyes. The dyes synthesized according to the affinity concept of dye to polylactide exhibited excellent dyeing properties on polylactide compared with the commercial disperse dyes.  相似文献   

7.
Several cyanine dyes were found to protect K562 leukemia cells against toxicity mediated by cis-di(4-sulfonatophenyl)diphenylporphine (TPPS2) and light. Most cyanine dyes derived from dimethylindole were better photoprotectors than cyanine dyes with other structures. This correlated with the fact that cyanine dyes derived from dimethylindole were predominately monomeric at millimolar concentrations within K562 cells, while other cyanine dyes formed aggregates. For cyanine dyes that are derived from dimethylindole and have absorption band wavelengths greater than 700 nm, fluorescence-energy transfer from TPPS2 to the cyanine dye was the most important mechanism for photoprotection. There was no spectroscopic evidence for complex formation between the cyanine dyes and TPPS2. The dimethylindole derivative, 1,1',3,3,3',3'-hexamethylindodicarbocyanine, was an excellent photoprotector, but a poor quencher of TPPS2 fluorescence and a relatively poor singlet-oxygen quencher. This cyanine dye may act by quenching excited triplet TPPS2. Singlet-oxygen quenching may contribute to the photoprotection provided by cyanine dyes not derived from dimethylindole. Differences in the subcellular distribution of the various cyanine dyes studied may have contributed to the different apparent mechanisms of photoprotection.  相似文献   

8.
Dye-sensitized solar cells(DSSCs) have attracted significant attention as alternatives to conventional silicon-based solar cells owing to their low-cost production,facile fabrication,excellent stability and high power conversion efficiency(PCE).The dye molecule is one of the key components in DSSCs since it significant influence on the PCE,charge separation,light-harvesting,as well as the device stability.Among various dyes,easily tunable phenothiazine-based dyes hold a large proportion and achieve impressive photovoltaic performances.This class of dyes not only has superiorly non-planar butterfly structure but also possesses excellent electron donating ability and large π conjugated system.This review summarized recent developments in the phenothiazine dyes,including small molecule phenothiazine dyes,polymer phenothiazine dyes and phenothiazine dyes for co-sensitization,especially focused on the developments and design concepts of small molecule phenothiazine dyes,as well as the correlation between molecular structures and the photovoltaic performances.  相似文献   

9.
10.
This review attempts to identify proteins which selectively interact with immobilised triazine dyes such as Cibacron blue F3GA and Procion red HE 3B. Different support matrices are compared by examining the capacities of these dyes for proteins. Various approaches to the immobilisation of triazine dyes are considered together with the use of spacers. Some theories of the mechanism of protein retardation by immobilised dyes are discussed. A number of methods are suggested for the measurement of dye concentrations and for the modification of the binding of proteins to dye columns. The variety of elution methods is compared with a view to optimizing purifications. The scope of applications is reviewed as well as the choice of dye. Some advantages of triazine dyes over other affinity ligands are given. It is concluded that although no satisfactory mechanism for the binding of triazine dyes to proteins has yet been proposed, these dyes possess considerable potential for protein purification, particularly when applied on the large scale.  相似文献   

11.
利用UV-Vis吸收光谱仪和光化学反应器,研究了菁染料和份菁染料溶液的光降解动力学,认为染料在乙腈溶液中的光褪色反应服从假一级或零级动力学.利用GC/MS光谱仪检测了染料的光降解产物.与相应的份菁染料相比,携带正电荷的菁染料具有相对较好的光稳定性.研究结果表明,菁染料光降解反应的中间体可能是染料的半氧化态Dye+,并利用纳秒级闪光光解技术研究了Dye+的瞬态吸收光谱.  相似文献   

12.
This paper describes the results of an investigation of the interparticle interactions and reactivities in the assembly of gold nanoparticles mediated by cyanine dyes. The combination of the positively charged indolenine cyanine dyes and the negatively charged gold nanoparticles is shown to form a J-aggregate bridged assembly of nanoparticles, in addition to hydrophobic interparticle and electrostatic dye-particle interactions. Such interparticle interactions and reactivities are studied by probing the absorption of J-aggregates and fluorescence from the dyes and the surface plasmon resonance absorption from the nanoparticles. The J-aggregation of the dyes adsorbed on the nanoparticles is shown to play an important role in the assembly of nanoparticles. The spectral evolution of the J-band of the dyes and the surface plasmon resonance band of the nanoparticles was found to be sensitive to the nature of the charge and the structure of the dyes. The fluorescence quenching for the dyes was shown to be quantitatively related to the surface coverage of the dyes on the nanocrystal surfaces. These findings have provided important information for assessing a two-step process involving a rapid adsorption of the dyes on the nanoparticles and a subsequent assembly of the nanoparticles involving a combination of interparticle J-aggregation and hydrophobic interactions of the adsorbed dyes. The results are discussed in terms of the structural effects of the dyes, and the interparticle molecular interactions and reactivities, which provide important physical and chemical insights into the design of dye-nanoparticle structured functional nanomaterials.  相似文献   

13.
设计合成了3种两端杂环氮原子上具有不同取代基的苯并噻唑类不对称三甲川菁染料,并对染料的结构进行了表征。 测试了染料在乙醇中的吸收和荧光发射光谱,染料的最大吸收值和荧光发射值分别在629~635 nm和656~672 nm之间。 染料8、9和10的斯托克斯位移分别为23、37和27 nm。 染料在溶剂中基本无荧光,荧光量子产率小于0.021,可以极大的降低染料自身的荧光背景干扰。 染料的光降解实验表明,两端杂环氮原子苄基取代后可以明显增强染料的光稳定性。 测试循环伏安曲线得到染料的氧化电位分别为0.535、0.456和0.399 V,氧化电位越大,光降解速率常数越小,与光降解实验得到的降解速率常数结果一致。  相似文献   

14.
A simple and rapid analytical method for the determination of trace levels of five sulphonated and azo sulphonated reactive dyes: Cibacron Reactive Blue 2 (C-Blue, trisulphonated dye), Cibacron Reactive Red 4 (C-Red, tetrasulphonated azo dye), Cibacron Reactive Yellow 2 (C-Yellow, trisulphonated azo dye), Levafix Brilliant Red E-4BA (L-Red, trisulphonated dye), and Levafix Brilliant Blue E-4BA (L-Blue, disulphonated dye) in water is presented. Initially, the dyes were preconcentrated from 250 ml of water samples with solid-phase extraction using natural zeolite sample previously modified with a microemulsion. The modified zeolite exhibited an excellent extraction for the dyes from solution. The parameters that influence quantitative recovery of reactive dyes like amount of extractant, volume of dye solution, pH, ionic strength, and extraction-elution flow rate were varied and optimized. After elution of the adsorbed dyes, the concentration of dyes was determined spectrophotometrically with the aid of principle component regression (PCR) method without separation of dyes. The results obtained from PCR method were comparable to those obtained from HPLC method confirming the effectiveness of the proposed method. With the aid of SPE by M-zeolite, the concentration of dyes could be reproducibly detected over the range 25-200 ppb for C-Yellow and L-Blue and from 50 to 250 ppb for C-Blue, C-Red, and L-Red. The multivariate detection limits of dyes were found to be 15 ppb for C-Yellow and L-Blue and 25 ppb for C-Blue, C-Red, and L-Red dyes. The proposed chemometric method gave recoveries from 85.4 to 115.3% and R.S.D. from 1.0 to 14.5% for determination of the five dyes without any prior separation for solutes.  相似文献   

15.
Covalent derivatization of proteins with fluorescent dyes prior to separation is increasingly used in proteomic research. This paper examines the properties of several commercially available iodoacetamide and maleimide dyes and discusses the conditions and caveats for their use in labeling of proteomic samples. The iodoacetamide dyes BODIPY TMR cadaverine IA and BODIPY Fl C(1)-IA were highly specific for cysteine residues and showed little or no nonspecific labeling even at very high dye:thiol ratios. These dyes also showed minimal effects on pI's of standard proteins. Some iodoacetamide dyes, (5-TMRIA and eosin-5-iodoacetamide) and some maleimide dyes (ThioGlo I and Rhodamine Red C(2) maleimide) exhibited nonspecific labeling at high dye:thiol ratios. Labeling by both iodoacetamide and maleimide dyes was inhibited by tris(2-carboxyethyl)phosphine (TCEP); interactions between TCEP and dye were also observed. Thiourea, an important component of sample solubilization cocktails, inhibited labeling of proteins with iodoacetamide dyes but not with maleimide dyes. Maleimide dyes may serve as an alternative for labeling proteins where it is essential to have thiourea in the solubilization buffer. Covalent derivatization by BODIPY TMR cadaverine IA, BODIPY Fl C(1)-IA or Rhodamine Red C(2) maleimide was also demonstrated to be compatible with in-gel digestion and peptide mass fingerprinting by matrix assisted laser desorption/ionization-mass spectrometry and allowed successful protein identification.  相似文献   

16.
The scope of polarography and voltammetry in analyzing azo dyes, anthraquinone-, polycondensed aromatic and vat dyes, di- and triarylcarbonium and heterocyclic dyes, nitro-, nitroso dyes and nitro intermediates, intermediates such as sulphonation products of 2-naphthol, diazonium salts and diazonium compounds is outlined. In view of much tougher future toxicological and environmental constraints and new outlets for dyes in modern high technology industries, polarography and voltammetry may find new and wider application and recognition.  相似文献   

17.
Six fungal isolates belong to Aspergillus niger, Penicillium spp., and Pleurotus osstreatus were used for decolourization activities of some acid and reactive dyes, after they screened for optimum efficiency and the condition for temperature and pH were optimized The results obtained indicated that Pleurotus osstreatus and Aspergillus niger 1 and 2 are more efficient than Penicillium spp., with the two kinds of dyes used. The results also revealed that, the maximum degradation activities of these isolates for acid dyes was at pH 5 after 9 days incubation period and at pH 5-6, for reactive dyes. Simulated and actual waste water samples were used in the experiments. Fungi decolourization of synthetic dyes according to their life state group 1: (living cells) to biodegradation and biosorb dyes. The major mechanism is biodegradation because they can produce the lignin modifying enzymes, lactose, manganese peroxides (Lip) to mineralize synthetic lignin of dyes. Group 2: dead cells (Fungal biomass) to adsorb dyes.  相似文献   

18.
Four derivatives of 5,5',6,6'-tetrachlorobenzimidazolocarbocyanine iodide with different long alkyl chain substituents in N-position of polymethine chromophore have been used for investigating the influence of hydrophobicity of dyes on the aggregation.It has been found that all dyes formed monomeric species in methyl alcohol. However, after addition of water to CH_3OH to change the polarity of the solvent, difference between dyes appeared.Addition of inorganic salt facilitated the J-aggregation of easy soluble dye, but it seems useless for the sparely soluble dye.Platelets cut from AgBr polycrystal or pressed AgBr powder have been used as substrate for adsorbing dyes. After addition of hexanoic acid, eventually the J-aggregate on AgBr surface could be destroyed.Voltammetry is a useful tool to investigate the interaction between dyes and AgBr. Experimental results showed that the longer the carbon chain substituents is, the stronger the interaction between AgBr and dyes would be.  相似文献   

19.
The visible absorption spectra of two oxazine dyes, brilliant cresyl blue and nile blue, in aqueous and aqueous urea solutions (0.01-1 M) were studied as a function of the dye concentration. Due to structural similarity of the investigated dyes, their spectral features were compared. The dimerization behavior of the dyes in water with or without urea was analyzed in terms of monomer-dimer equilibrium. The nature and structure of the interacting pairs for these dyes were discussed using the exciton theory. The dimerization constant values of the dyes in aqueous and aqueous urea solutions were calculated. For both the dyes in aqueous urea solutions, a reduction in dimer formation was observed. The excitonic parameters were compared with those of oxazine-1, which is structurally similar to the investigated dyes.  相似文献   

20.
Chalcogenorhodamine dyes bearing phosphonic acids and carboxylic acids were compared as sensitizers of nanocrystalline TiO(2) in dye-sensitized solar cells (DSSCs). The dyes were constructed around a 3,6-bis(dimethylamino)chalcogenoxanthylium core and varied in the 9 substituent: 5-carboxythien-2-yl in dyes 1-E (E = O, Se), 4-carboxyphenyl in dyes 2-E (E = O, S), 5-phosphonothien-2-yl in dyes 3-E (E = O, Se), and 4-phosphonophenyl in dyes 4-E (E = O, Se). All dyes adsorbed to TiO(2) as mixtures of H aggregates and monomers, which exhibited broadened absorption spectra relative to those of purely amorphous monolayers. Surface coverages of dyes and the extent of H aggregation varied minimally with the surface-attachment functionality, the structure of the 9-aryl group, and the identity of the chalcogen heteroatom. Carboxylic acid-functionalized dyes 1-E and 2-E desorbed rapidly and completely from TiO(2) into acidified CH(3)CN, but phosphonic acid-functionalized dyes 3-E and 4-E persisted on TiO(2) for days. Short-circuit photocurrent action spectra of DSSCs corresponded closely to the absorptance spectra of dye-functionalized films; thus, H aggregation did not decrease the electron-injection yield or charge-collection efficiency. Maximum monochromatic incident photon-to-current efficiencies (IPCEs) of DSSCs ranged from 53 to 95% and were slightly higher for carboxylic acid-functionalized dyes 1-E and 2-E. Power-conversion efficiencies of DSSCs under white-light illumination were low (<1%), suggesting that dye regeneration was inefficient at high light intensities. The photoelectrochemical performance (under monochromatic or white-light illumination) of 1-E and 2-E decayed significantly within 20-80 min of the assembly of DSSCs, primarily because of the desorption of the dyes. In contrast, the performance of phosphonic acid-functionalized dyes remained stable or improved slightly on similar timescales. Thus, replacing carboxylic acids with phosphonic acids increased the inertness of chalcogenorhodamine-TiO(2) interfaces without greatly impacting the aggregation of dyes or the interfacial electron-transfer reactivity.  相似文献   

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