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1

Natural dyeing of wool and hair with indigo carmine (C.I. Natural Blue 2), a renewable resource based blue dye  

Microsoft Academic Search

Indigo carmine can be used as a source of blue dye for wool and hair dyeing. The option to use indigo carmine in combination with other natural dyes in a one-bath procedure as a hybrid dyeing concept is of interest both for natural dyeing and for coloration of hair. The present study shows that indigo carmine dyeing on wool exhibits

Sunsanee Komboonchoo; Thomas Bechtold

2009-01-01

2

Electrochemical degradation of the dye indigo carmine at boron-doped diamond anode for wastewaters remediation  

Microsoft Academic Search

Here we demonstrate that anodic oxidation with a boron-doped diamond (BDD) electrode can be applied to the remediation of wastewaters containing indigo carmine. This environmentally friendly method decontaminates completely acid and alkaline aqueous solutions of this dye. The degradation rate increases with increasing current and dye concentration. Indigo carmine is more rapidly removed in alkaline than in acid medium, but

Salah Ammar; Ridha Abdelhedi; Cristina Flox; Conchita Arias; Enric Brillas

2006-01-01

3

The history, chemistry and modes of action of carmine and related dyes.  

PubMed

Carmine has been used in biological staining to demonstrate selectively nuclei, chromosomes or mucins, depending on the formulation. Throughout its history in science, complaints and frustrations have been expressed about dye quality. Inconsistencies in dye quality or identity have prevented thorough understanding of staining mechanisms and have caused many stain solutions to behave unsatisfactorily. The aim of this review is to (1) detail causes of these problems, which are rooted in history, geography and production, (2) offer ways to minimize problems and (3) provide modern explanations for stain behavior. Carmine is a "semi-synthetic" dye, i.e., a complex of aluminum and the natural dye cochineal (carminic acid). Carmine shows considerable batch-to-batch variability. Geography, politics, history, agricultural practices and iconography all contribute to the variability of cochineal. In addition, widely divergent manufacturing methods are used to produce carmine. Also, confusion in terminology has led to mislabeling. Pressure from the food industry for a more satisfactory colorant for acidic foods led to the introduction of a new dye, aminocarminic acid, which could enter the biological market inadvertantly. Improved methods of analysis should help the certification process by the Biological Stain Commission. Further standardization could be achieved by replacing most of the methods of solubilizing carmine. The majority of these methods use heat, which is likely to damage the dye molecule. Fortunately, carmine is readily dissolved by raising the pH of the aqueous solvent above 12, and a new form of the dye, now available commercially, is soluble in water without the need for heat or pH adjustment. Chemical structures and physical properties of carminic acid, carmine, aminocarminic acid and kermesic acid are reviewed. A new configuration for carmine is proposed, as well as possible changes to carminic acid and carmine molecules as a result of decomposition caused by heating. Each of the major classes of carmine-based stains is described as are possible mechanisms of attachment to specific substrates. Glycogen binds carmine through hydrogen bonding, and it is here that carmine decomposed by heat could have the greatest detrimental impact. Nuclei and chromosomes are stained via coordination bonds, perhaps supplemented by hydrogen bonds. Finally, acidic mucins react ionically with carmine. Specificity in the latter case may be due to unique polymeric carmine molecules that form in the presence of aluminum chloride. PMID:18074265

Dapson, R W

2007-08-01

4

Aqueous two-phase systems: An efficient, environmentally safe and economically viable method for purification of natural dye carmine  

Microsoft Academic Search

Partition of the natural dye carmine has been studied in aqueous two-phase systems prepared by mixing aqueous solutions of polymer or copolymer with aqueous salt solutions (Na2SO4 and Li2SO4). The carmine dye partition coefficient was investigated as a function of system pH, polymer molar mass, hydrophobicity, system tie-line length and nature of the electrolyte. It has been observed that the

Aparecida Barbosa Mageste; Leandro Rodrigues de Lemos; Guilherme Max Dias Ferreira; Maria do Carmo Hespanhol da Silva; Luis Henrique Mendes da Silva; Renata Cristina Ferreira Bonomo; Luis Antonio Minim

2009-01-01

5

Indigo carmine dye-assisted lymphatic-sparing laparoscopic palomo varicocelectomy in children.  

PubMed

The ideal method for varicocelectomy in children remains controversial. We present our experience with dye-assisted lymphatic-sparing laparoscopic varicocelectomy (LSLV) in children, which overcomes the limitations of previously described techniques. Materials and methods: Five consecutive LSLVs were performed over a period of three years on children with a mean age of twelve years. The varicocele grade was three in one case and grade 2 in four cases, respectively. A left subdartos injection of 2 ml of Indigo carmine dye was done using a 25-gauge needle at ten minutes before an operation. A scrotal injection of lymphatic dye was utilized to spare at least one lymphatic and the remaining spermatic vessels were divided. Results: Lymphatic-sparing was accomplished in all cases. No peri-operative complication was noted. We spared one lymphatic channel in one patient (20%) and two channels in four patients (80%). There were no cases of hydrocele or residual varicocele. Conclusion: Dye-assisted LSLV is easily accomplished with an excellent surgical outcome and sparing one or two lymphatics appears to be sufficient to avoid secondary hydrocele. J. Med. Invest. 61: 151-155, February, 2014. PMID:24705760

Ishibashi, Hiroki; Mori, Hiroki; Yada, Keigo; Shimada, Mitsuo; Sogami, Tomoko; Nii, Akira

2014-01-01

6

On the structure of carminic acid and carmine  

Microsoft Academic Search

The chemical mechanism and histochemical significance of carmine stains are not yet understood. To determine possible effects of dye configuration on staining patterns we built models of dye molecules with the Stuart-Briegleb-type of atomic models. However, steric hindrance prevented construction of carmine according to the formula suggested by Harms. A review of recent chemical literature showed that the widely accepted

Susan N. Meloan; Linda S. Valentine; Holde Puchtler

1971-01-01

7

Stability of ?-Irradiated Carmine  

NASA Astrophysics Data System (ADS)

Carmine is a dye used mainly for coloring food products and galenicals but also in inks. As food irradiation is becoming a regular treatment for food preservation, it is desirable to have a proper knowledge about the radiation sensitivity of additives that can be included in the food formula. The aim of this work was to establish the radiation stability of carmine against Co-60 gamma radiation. Samples of 50% pure carmine powder as well as 50%, 10% and 5% aqueous solutions were irradiated in a Gammacell 220, dose rate of about 5.2 kGy/h, with doses of 0, 1, 2, 4, 8, 16 and 32 kGy. Spectrophotometric readings at 494 nm show a slight decrease of the absorbance as a function of dose: Samples irradiated with 4 and 32 kGy retained 95% and 90% of absorbance of the unirradiated samples respectively. These results indicate a rather good stability of carmine against ?-irradiation.

Cosentino, Hélio M.; Fontenele, Rinaldo S.; DelMastro, Nélida L.

2005-01-01

8

Intraoperative contrast-enhanced sonographic portography combined with indigo carmine dye injection for anatomic liver resection in hepatocellular carcinoma: a new technique.  

PubMed

We present a method of intraoperative contrast-enhanced sonographic portography combined with indigo carmine dye injection for anatomic liver resection in hepatocellular carcinoma. During surgery, before dye infusion into the feeding portal vein, the targeted portal vein branch was directly punctured, and a microbubble contrast agent was administered under sonographic guidance. Simultaneous enhancement of the resected hepatic parenchyma with a microbubble contrast agent and blue dye improved estimation of the segmental border in the cutting plane and the tumor resection margin during liver surgery. PMID:24958416

Park, Yang Shin; Lee, Chang Hee; Park, Pyoung-Jae; Kim, Kyeong Ah; Park, Cheol Min

2014-07-01

9

Raman spectroscopy of organic dyes adsorbed on pulsed laser deposited silver thin films  

NASA Astrophysics Data System (ADS)

The results of a surface-enhanced Raman scattering (SERS) study performed on representative organic and inorganic dyes adsorbed on silver nanostructured thin films are presented and discussed. Silver thin films were deposited on glass slides by focusing the beam from a KrF excimer laser (wavelength 248 nm, pulse duration 25 ns) on a silver target and performing the deposition in a controlled Ar atmosphere. Clear Raman spectra were acquired for dyes such as carmine lake, garanza lake and brazilwood overcoming their fluorescence and weak Raman scattering drawbacks. UV-visible absorption spectroscopy measurements were not able to discriminate among the different chromophores usually referred as carmine lake (carminic, kermesic and laccaic acid), as brazilwood (brazilin and brazilein) and as garanza lake (alizarin and purpurin). SERS measurements showed that the analyzed samples are composed of a mixture of different chromophores: brazilin and brazilein in brazilwood, kermesic and carminic acid in carmine lake, alizarin and purpurin in garanza lake. Detection at concentration level as low as 10-7 M in aqueous solutions was achieved. Higher Raman intensities were observed using the excitation line of 632.8 nm wavelength with respect to the 785 nm, probably due to a pre-resonant effect with the molecular electronic transitions of the dyes.

Fazio, E.; Neri, F.; Valenti, A.; Ossi, P. M.; Trusso, S.; Ponterio, R. C.

2013-08-01

10

Matrix-assisted laser desorption and electrospray ionization mass spectrometry of carminic acid isolated from cochineal  

NASA Astrophysics Data System (ADS)

Carminic acid, isolated from cochineal, was analyzed by matrix-assisted laser desorption/ionization (MALDI) and electrospray mass spectrometry (ESI-MS). Application of both techniques to the analysis of carminic acid suspended in linseed oil and applied to a piece of canvas, demonstrated the ability of MALDI and ESI-MS to identify this organic dye in a mixture as those used in easel painting.

Maier, Marta S.; Parera, Sara D.; Seldes, Alicia M.

2004-04-01

11

Preparation of mesoporous poly (acrylic acid)/SiO2 composite nanofiber membranes having adsorption capacity for indigo carmine dye  

NASA Astrophysics Data System (ADS)

Mesoporous poly (acrylic acid)/SiO2 (PAA/SiO2) composite nanofiber membranes functionalized with mercapto groups were fabricated by a sol-gel electrospinning method, and their adsorption capacity for indigo carmine was investigated. The membranes were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, x-ray powder diffraction (XRD), and nitrogen adsorption-desorption measurement. SEM and TEM observation results showed that the PAA/SiO2 fibers had diameters between 400-800 nm and mesopores with an average pore size of 3.88 nm. The specific surface area of the mesoporous nanofiber membranes was 514.89 m2/g. The characteristic peaks for mercapto group vibration in FTIR and Raman spectra demonstrated that the mercapto groups have been incorporated into the silica skeleton. The adsorption isotherm data of indigo carmine on the membranes fit well with Redlich-Peterson model, and the maximum adsorption capacity calculated was 523.11 mg/g. It was found that the removal rate of indigo carmine by the membranes reached a maximum of 98% in 90 min and the adsorption kinetics followed a pseudo-second-order model. The high adsorption capacity of PAA/SiO2 nanofiber membrane makes it a promising adsorbent for indigo carmine removal from the wastewater.

Xu, Ran; Jia, Min; Li, Fengting; Wang, Hongtao; Zhang, Bingru; Qiao, Junlian

2012-03-01

12

Photodegradation of indigo carmine and methylene blue dyes in aqueous solution by SiC-TiO2 catalysts prepared by sol-gel.  

PubMed

Indigo carmine and methylene blue dyes in aqueous solution were photodegraded using SiC-TiO(2) catalysts prepared by sol-gel method. After thermal treatment at 450°C, SiC-TiO(2) catalysts prepared in this work showed the presence of SiC and TiO(2) anatase phase. Those compounds showed specific surface area values around 22-25 m(2)g(-1), and energy band gap values close to 3.05 eV. In comparison with TiO(2) (P25), SiC-TiO(2) catalysts showed the highest activity for indigo carmine and methylene blue degradation, but this activity cannot be attributed to the properties above mentioned. Therefore, photocatalytic performance is due to the synergy effect between SiC and TiO(2) particles caused by the sol-gel method used to prepare the SiC-TiO(2) catalysts. TiO(2) nanoparticles are well dispersed onto SiC surface allowing the transfer of electronic charges between SiC and TiO(2) semiconductors, which avoid the fast recombination of the electron-hole pair during the photocatalytic process. PMID:22464585

Gómez-Solís, Christian; Juárez-Ramírez, Isaías; Moctezuma, Edgar; Torres-Martínez, Leticia M

2012-05-30

13

Electrochemical analysis of natural solid organic dyes and pigments  

Microsoft Academic Search

Square-wave voltammetry of solid naphthoquinone, anthraquinone, and flavone dyes, carmine, cochineal red, indigo, and Prussian blue, was compared to microanalysis (sample consumption <1 mg) of traditional painting pigments and dyes without their preliminary dissolution. Electrochemical analysis was also performed after the samples' hydrolysis simultaneously with thin-layer chromatography. Anthraquinone-based pigments and Prussian blue are reversibly reduced, cochineal red and lac dyes are

T. Grygar; Š. Ku?ková; D. Hradil; J. Hradilová

2003-01-01

14

Indigo carmine: An organic crystal as a positive-electrode material for rechargeable sodium batteries  

PubMed Central

Using sodium, instead of lithium, in rechargeable batteries is a way to circumvent the lithium's resource problem. The challenge is to find an electrode material that can reversibly undergo redox reactions in a sodium-electrolyte at the desired electrochemical potential. We proved that indigo carmine (IC, 5,5?-indigodisulfonic acid sodium salt) can work as a positive-electrode material in not only a lithium-, but also a sodium-electrolyte. The discharge capacity of the IC-electrode was ~100?mAh g?1 with a good cycle stability in either the Na or Li electrolyte, in which the average voltage was 1.8?V vs. Na+/Na and 2.2?V vs. Li+/Li, respectively. Two Na ions per IC are stored in the electrode during the discharge, testifying to the two-electron redox reaction. An X-ray diffraction analysis revealed a layer structure for the IC powder and the DFT calculation suggested the formation of a band-like structure in the crystal.

Yao, Masaru; Kuratani, Kentaro; Kojima, Toshikatsu; Takeichi, Nobuhiko; Senoh, Hiroshi; Kiyobayashi, Tetsu

2014-01-01

15

Degradation of organic dyes by corona discharge.  

National Technical Information Service (NTIS)

Several dyes in water were individually exposed to corona discharge. Light absorbance decreased for all organic dyes with time. Absorbance losses with methylene blue, malachite green, and new coccine were studied. The loss of color was followed using an i...

S. C. Goheen M. McCulloch D. E. Durham W. O. Heath

1992-01-01

16

Influence of pulse width on decolorization efficiency of organic dye by discharge inside bubble in water  

NASA Astrophysics Data System (ADS)

Decolorization of an organic dye by discharge in high conductive water using a pulsed power generator and a discharge reactor was investigated. The discharge reactor consisted of a glass tube and a tungsten wire inserted into the glass tube, which was immersed in the water. Room air was injected into the glass tube to generate bubbles in the water. High voltage pulses were generated by an inductive-energy storage system using semiconductor opening switch (SOS) and by a magnetic pulse compression circuit. Fast recovery diodes were used as SOS diode in the inductive-energy storage system. The pulse width was changed in range from 10 to 1200 ns. The high voltage was applied to the tungsten wire. Indigo carmine was employed as a specimen to evaluate decolorization efficiency. Potassium nitrate was used to adjust the solution conductivity. The dye solution was successfully decolorized at 7 mS/cm conductivity. Energy efficiency for decolorization increased from 0.680 to 55.6 mg/Wh with decreasing the pulse width from 1200 to 10 ns owing to the reduction of ohmic loss.

Kawano, S.; Wada, K.; Kakuta, T.; Takaki, K.; Satta, N.; Takahashi, K.

2013-06-01

17

Photophysics of some styryl thiazolo quinoxaline dyes in organic media  

Microsoft Academic Search

The photophysics of a new class of styryl dyes, 2-styryl thiazolo quinoxaline (STQ) based structures was investigated in organic solvents and organized molecular assemblies. The absorption, steady state and time-resolved fluorescence characteristics of the STQ dyes in low-viscosity organic solvents are consistent with a single species in the ground and excited state. The one electron electrochemical oxidation and reduction potentials

A. S. R. Koti; B. Bhattacharjee; N. S. Haram; Ranjan Das; N. Periasamy; N. D. Sonawane; D. W. Rangnekar

2000-01-01

18

Optical properties of organic dyes in nanoporous zeolite crystals  

NASA Astrophysics Data System (ADS)

Organic dye molecules of styryl 7 were introduced into the channels of AlPO4-5 single crystals. Polarized absorption and photoluminescence spectra of the dye molecules were investigated. The polarization angle dependence of the absorption and photoluminescence intensity indicates that the dye molecules are highly oriented in the channels. The hexagonal-shaped AlPO4-5 single crystal serves as a natural microcavity for lasing action of the dye molecules. The microcavity modes of the lasing action were also demonstrated.

Li, Irene L.; Tang, Z. K.; Xiao, X. D.; Yang, C. L.; Ge, W. K.

2003-09-01

19

Organic synthetic transformations using organic dyes as photoredox catalysts.  

PubMed

The oxidizing ability of organic dyes is enhanced significantly by photoexcitation. Radical cations of weak electron donors can be produced by electron transfer from the donors to the excited states of organic dyes. The radical cations thus produced undergo bond formation reactions with various nucleophiles. For example, the direct oxygenation of benzene to phenol was made possible under visible-light irradiation of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) in an oxygen-saturated acetonitrile solution of benzene and water via electron transfer from benzene to the triplet excited state of DDQ. 3-Cyano-1-methylquinolinium ion (QuCN(+)) can also act as an efficient photocatalyst for the selective oxygenation of benzene to phenol using oxygen and water under homogeneous and ambient conditions. Alkoxybenzenes were also obtained when water was replaced by alcohol under otherwise identical experimental conditions. QuCN(+) can also be an effective photocatalyst for the fluorination of benzene with O2 and fluoride anion. Photocatalytic selective oxygenation of aromatic compounds was achieved using an electron donor-acceptor-linked dyad, 9-mesityl-10-methylacridinium ion (Acr(+)-Mes), as a photocatalyst and O2 as the oxidant under visible-light irradiation. The electron-transfer state of Acr(+)-Mes produced upon photoexcitation can oxidize and reduce substrates and dioxygen, respectively, leading to the selective oxygenation and halogenation of substrates. Acr(+)-Mes has been utilized as an efficient organic photoredox catalyst for many other synthetic transformations. PMID:24984977

Fukuzumi, Shunichi; Ohkubo, Kei

2014-08-28

20

Photoemission features of organic dyes in matrix of porous silicon  

NASA Astrophysics Data System (ADS)

The influence of sorption of the organic dye DCM (LC 6500) on the character of photoluminescence as a result of interaction of the solution with porous silicon surface containing nanocrystalline Si was investigated.

Ivannikov, S. N.; Kavetskaya, I. V.; Kashkarov, V. M.; Len'shin, A. S.

2013-01-01

21

Violet-to-red photoluminescence of spiro-TAD organic films doped with different organic dyes  

NASA Astrophysics Data System (ADS)

Photoluminescence (PL) and photoluminescence excitation (PLE) spectra of undoped spiro-TAD films and spiro-TAD films doped either by the organic dyes coumarin 7 or DCM as well as by both of these dyes simultaneously were investigated at different dye concentrations. A widened PL spectrum caused by doping was encountered and violet-to-red emission was obtained. It was established that excitation of the dyes is realized most efficiently through spiro-TAD. The overall integral PL intensity of the coumarin 7 doped films increased with dye concentration due to the suppression of nonradiative recombination in the film caused by a transfer of spiro-TAD excitation energy to the dye molecules. Mainly radiative energy transfer from semiconductor to dye molecules occurs in the case of DCM doping. No mutual influence on the luminescence of both dyes in the spiro-TAD film was observed and as a consequence, the PL band intensity of each dye can be adjusted separately.

Osipov, K. A.; Pavlovskii, V. N.; Lutsenko, E. V.; Gurskii, A. L.; Effendiev, T. S.; Katarkevich, V. N.; Yablonskii, G. P.; van Gemmern, P.; Zimmermann, C.; Jessen, F.; Kalisch, H.; Jansen, R. H.; Heuken, M.

2007-05-01

22

Organic synthetic dye degradation by modified pinhole discharge  

Microsoft Academic Search

The aim of this work was to investigate the possibility of applying a high voltage pulsed electrical discharges for dye wastewater\\u000a treatment. Commercial organic monochlorotriazine reactive dye of the anthraquinone type C.I. Reactive Blue 49 (RB49) was chosen\\u000a as a representative of persistent and recalcitrant wastewater pollutant. The modified pinhole discharge flow-through reactor\\u000a was used to treat such type of

A. Lon?ari? Boži?; N. Koprivanac; P. Šunka; M. ?lupek; V. Babický

2004-01-01

23

Organic dyes with a novel anchoring group for dye-sensitized solar cell applications  

Microsoft Academic Search

Two novel trialkylsilyl-containing organic sensitizers (JK-53 and JK-54) have been designed and synthesized. Nanocrystalline TiO2–silica-based dye-sensitized solar cells (DSSCs) were fabricated using these dyes. Under standard global AM 1.5 solar conditions, the JK-53-sensitized cell gave a short-circuit photocurrent density (Jsc) of 6.37mAcm?2, an open-circuit voltage (Voc) of 0.70V, and a fill factor of 0.74. These values correspond to an overall

Chul Baik; Duckhyun Kim; Moon-Sung Kang; Sang Ook Kang; Jaejung Ko; Mohammad K. Nazeeruddin; Michael Grätzel

2009-01-01

24

Organic polyaromatic hydrocarbons as sensitizing model dyes for semiconductor nanoparticles.  

PubMed

The study of interfacial charge-transfer processes (sensitization) of a dye bound to large-bandgap nanostructured metal oxide semiconductors, including TiO(2), ZnO, and SnO(2), is continuing to attract interest in various areas of renewable energy, especially for the development of dye-sensitized solar cells (DSSCs). The scope of this Review is to describe how selected model sensitizers prepared from organic polyaromatic hydrocarbons have been used over the past 15 years to elucidate, through a variety of techniques, fundamental aspects of heterogeneous charge transfer at the surface of a semiconductor. This Review does not focus on the most recent or efficient dyes, but rather on how model dyes prepared from aromatic hydrocarbons have been used, over time, in key fundamental studies of heterogeneous charge transfer. In particular, we describe model chromophores prepared from anthracene, pyrene, perylene, and azulene. As the level of complexity of the model dye-bridge-anchor group compounds has increased, the understanding of some aspects of very complex charge transfer events has improved. The knowledge acquired from the study of the described model dyes is of importance not only for DSSC development but also to other fields of science for which electronic processes at the molecule/semiconductor interface are relevant. PMID:20135672

Zhang, Yongyi; Galoppini, Elena

2010-04-26

25

Structure-performance correlations of organic dyes with an electron-deficient diphenylquinoxaline moiety for dye-sensitized solar cells.  

PubMed

The high performances of dye-sensitized solar cells (DSSCs) based on seven new dyes are disclosed. Herein, the synthesis and electrochemical and photophysical properties of a series of intentionally designed dipolar organic dyes and their application in DSSCs are reported. The molecular structures of the seven organic dyes are composed of a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron-deficient diphenylquinoxaline moiety integrated in the ?-conjugated spacer between the electron donor and acceptor moieties. The DSSCs based on the dye DJ104 gave the best overall cell performance of 8.06?%; the efficiency of the DSSC based on the standard N719 dye under the same experimental conditions was 8.82?%. The spectral coverage of incident photon-to-electron conversion efficiencies extends to the onset at the near-infrared region due to strong internal charge-transfer transition as well as the effect of electron-deficient diphenylquinoxaline to lower the energy gap in these organic dyes. A combined tetraphenyl segment as a hydrophobic barrier in these organic dyes effectively slows down the charge recombination from TiO2 to the electrolyte and boosts the photovoltage, comparable to their Ru(II) counterparts. Detailed spectroscopic studies have revealed the dye structure-cell performance correlations, to allow future design of efficient light-harvesting organic dyes. PMID:25042065

Li, Sie-Rong; Lee, Chuan-Pei; Yang, Po-Fan; Liao, Chia-Wei; Lee, Mandy M; Su, Wei-Lin; Li, Chun-Ting; Lin, Hao-Wu; Ho, Kuo-Chuan; Sun, Shih-Sheng

2014-08-01

26

Fast rise air spark pump for organic dye lasers  

Microsoft Academic Search

A specially constructed capacitor with low inductance is used to produce an air spark with short rise time, which is able to pump organic dye lasers with high efficiency. For Rhodamin 6 G we observed a threshold energy for stimulated emission of 3 Ws.

F. Aussenegg; J. Schubert

1969-01-01

27

Organic synthetic dye degradation by modified pinhole discharge  

NASA Astrophysics Data System (ADS)

The aim of this work was to investigate the possibility of applying a high voltage pulsed electrical discharges for dye wastewater treatment. Commercial organic monochlorotriazine reactive dye of the anthraquinone type C.I. Reactive Blue 49 (RB49) was chosen as a representative of persistent and recalcitrant wastewater pollutant. The modified pinhole discharge flow-through reactor was used to treat such type of contaminant. Applying HV pulses 30 kV, 3.15 J/pulse, 50 Hz repetition rate, complete decolorisation and partial mineralization of RB49 has been reached and demonstrated by means of UV/VIS absorption, TOC and AOX measurements.

Lon?ari? Boži?, A.; Koprivanac, N.; Šunka, P.; ?lupek, M.; Babický, V.

2004-03-01

28

Organics Verification Study for Sinclair and Dyes Inlets, Washington  

SciTech Connect

Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington 1998 303(d) list of impaired waters because of fecal coliform contamination in marine water, metals in sediment and fish tissue, and organics in sediment and fish tissue. Because significant cleanup and source control activities have been conducted in the inlets since the data supporting the 1998 303(d) listings were collected, two verification studies were performed to address the 303(d) segments that were listed for metal and organic contaminants in marine sediment. The Metals Verification Study (MVS) was conducted in 2003; the final report, Metals Verification Study for Sinclair and Dyes Inlets, Washington, was published in March 2004 (Kohn et al. 2004). This report describes the Organics Verification Study that was conducted in 2005. The study approach was similar to the MVS in that many surface sediment samples were screened for the major classes of organic contaminants, and then the screening results and other available data were used to select a subset of samples for quantitative chemical analysis. Because the MVS was designed to obtain representative data on concentrations of contaminants in surface sediment throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, aliquots of the 160 MVS sediment samples were used in the analysis for the Organics Verification Study. However, unlike metals screening methods, organics screening methods are not specific to individual organic compounds, and are not available for some target organics. Therefore, only the quantitative analytical results were used in the organics verification evaluation. The results of the Organics Verification Study showed that sediment quality outside of Sinclair Inlet is unlikely to be impaired because of organic contaminants. Similar to the results for metals, in Sinclair Inlet, the distribution of residual organic contaminants is generally limited to nearshore areas already within the actively managed Puget Sound Naval Shipyard and Intermediate Maintenance Facility Superfund Site, where further source-control actions and monitoring are under way.

Kohn, Nancy P.; Brandenberger, Jill M.; Niewolny, Laurie A.; Johnston, Robert K.

2006-09-28

29

Fine-tuning the electronic structure of organic dyes for dye-sensitized solar cells.  

PubMed

A series of metal-free organic dyes exploiting different combinations of (hetero)cyclic linkers (benzene, thiophene, and thiazole) and bridges (4H-cyclopenta[2,1-b:3,4-b']dithiophene (CPDT) and benzodithiophene (BDT)) as the central ?-spacers were synthesized and characterized. Among them, the sensitizer containing the thiophene and CPDT showed the most broad incident photon-to-current conversion efficiency spectra, resulting in a solar energy conversion efficiency (?) of 6.6%. PMID:22882164

Gao, Peng; Tsao, Hoi Nok; Grätzel, Michael; Nazeeruddin, Mohammad K

2012-09-01

30

21 CFR 73.100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Cochineal extract; carmine. 73.100 Section 73...CERTIFICATION Foods § 73.100 Cochineal extract; carmine. (a) Identity. (1) The color additive cochineal extract is the concentrated solution...

2010-04-01

31

21 CFR 73.100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2010 CFR

... 2009-04-01 false Cochineal extract; carmine. 73.100 Section 73...CERTIFICATION Foods § 73.100 Cochineal extract; carmine. (a) Identity. (1) The color additive cochineal extract is the concentrated solution...

2009-04-01

32

Excited-states and Lightfastness of Organic Dyes and Pigments  

NASA Astrophysics Data System (ADS)

Organic dyes and pigments have been widely used as functional materials for silver halide photographic systems, ink-jet prints, and optical disks. For such applications, high lightfastness and good thermal properties are essential, but to date there have only been a small number of studies of these characteristics. In this paper we report our results concerning excited-states and lightfastness of these materials elucidated by a combination of several time-resolved spectroscopic measurements.

Miyashita, Yousuke

33

Detection of Bacillus anthracis spores: comparison of quantum dot and organic dye labeling agents  

Microsoft Academic Search

Organic dyes are routinely used in labeling assays and sensing of biological molecules. Semiconductor quantum dots (QDs) have attractive features, particularly good resistance to photobleaching and narrow emission bands, which make them potential replacements for organic dyes. Using a previously identified synthetic peptide, a QD, and the R-phycoerythrin (RPE) dye, we have examined various labeling strategies for detecting Bacillus anthracis

William C. Schumacher; Andrew J. Phipps; Prabir K. Dutta

2009-01-01

34

Sensitization of the Photoconductivity and Photo emf of Heavy Metal Azides Colored by Organic Dyes.  

National Technical Information Service (NTIS)

In order to study the dark transition of electrons between substrate and adsorbed dye, as well as the mechanism of optical sensitization of lead, silver and thallium azides colored by organic dyes, the authors measured their photoconductivity and photo em...

Y. V. Gavrishchenko G. G. Savelev Y. A. Zakrarov

1973-01-01

35

High-definition vs. standard-definition endoscopy with indigo carmine for the in vivo diagnosis of colonic polyps  

PubMed Central

Background There is growing evidence that indigo carmine chromoendoscopy is effective for the in vivo diagnosis of colonic polyps. However, the impact of colonoscope resolution on diagnostic accuracy has not been investigated. Objective We aimed to compare the effectiveness of in vivo diagnosis of small colonic polyps using indigo carmine dye spray with standard-definition and high-definition colonoscopes. Methods Procedures were performed using Fujinon colonoscopes and EPX 4400 processor. Fujinon standard-definition (SD) and high-definition (HD) colonoscopes were used, with the endoscopist blinded to colonoscope definition. Polyps <10?mm were assessed using 0.2% indigo carmine dye spray, with the predicted diagnosis recorded. In each case the kind of colonoscope (SD or HD) was recorded. Polyps were removed and sent for histological analysis, with the pathologist blinded to the diagnosis made by the endoscopist. The predicted diagnosis was compared with the true histology to calculate the accuracy, sensitivity and specificity of in vivo assessment using either SD or HD scopes. Results In total 237 polyps <10?mm in size were examined. There was no statistically significant difference for any of the measured parameters between SD and HD assessments, with an accuracy, sensitivity and specificity of 89%, 91% and 87% with SD colonoscopes and 92%, 96% and 84% with HD colonoscopes. Conclusions The accuracy of in vivo assessment of small colonic polyps with indigo carmine dye spray is excellent with standard-definition colonoscopes and is not improved with high-definition colonoscopes.

Longcroft-Wheaton, Gaius; Brown, James; Cowlishaw, David; Higgins, Bernard

2013-01-01

36

Crystallization control of organic dyes in self-organized microdomes  

NASA Astrophysics Data System (ADS)

A dewetting process of an evaporating solution is used to form micrometer-sized amorphous droplets, or domes, of the solute on substrates such as silicon, mica, glass, and indium-tin-oxide. The dome size can be controlled by the casting conditions. Higher concentration and slower evaporation of the solvent leads to larger domes. Upon annealing, the dyes may crystallize and form polycrystalline or single crystalline domes or crystalline fibers. Photophysical properties of the domes were investigated and it was found that the absorption and fluorescence spectra depend on the aggregate kind (polycrystalline or single crystalline) and the dome size.

Karthaus, Olaf; Kaga, Kazuaki; Kageyama, Hiroaki

2004-09-01

37

Theoretical design of thiazolothiazole-based organic dyes with different electron donors for dye-sensitized solar cells.  

PubMed

In this study, we have designed four novel organic donor-?-acceptor dyes (D1, D2, D3, D4), used for dye sensitized solar cells (DSSCs). The electron acceptor (anchoring) group was 2-cyanoacrylic for all dyes whereas the electron donor unit varied (coumarin, indoline, carbazole, triphenylamine) and the influence was investigated. These dyes, based on thiazolothiazole as ?-spacer, were studied by density functional theory (DFT) and its extensible time dependant DFT (TDDFT) approaches to shed light on how the ?-conjugation order influence the performance of the dyes in the DSSCs. The theoretical results have shown that the LUMO and HOMO energy levels of these dyes can be ensuring positive effect on the process of electron injection and dye regeneration. The trend of the calculated HOMO-LUMO gaps nicely compares with the spectral data. Key parameters in close connection with the short-circuit current density (Jsc), including light harvesting efficiency (LHE), injection driving force (?G(inject.)) and total reorganization energy (?total), were discussed. The calculated results of these dyes reveal that dye D2, with indoline as electron donor group, can be used as a potential sensitizer for TiO2 nanocrystalline solar cells due to its best electronic and optical properties and good photovoltaic parameters. PMID:24866090

Fitri, Asmae; Benjelloun, Adil Touimi; Benzakour, Mohammed; Mcharfi, Mohammed; Hamidi, Mohammed; Bouachrine, Mohammed

2014-11-11

38

Theoretical design of thiazolothiazole-based organic dyes with different electron donors for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

In this study, we have designed four novel organic donor-?-acceptor dyes (D1, D2, D3, D4), used for dye sensitized solar cells (DSSCs). The electron acceptor (anchoring) group was 2-cyanoacrylic for all dyes whereas the electron donor unit varied (coumarin, indoline, carbazole, triphenylamine) and the influence was investigated. These dyes, based on thiazolothiazole as ?-spacer, were studied by density functional theory (DFT) and its extensible time dependant DFT (TDDFT) approaches to shed light on how the ?-conjugation order influence the performance of the dyes in the DSSCs. The theoretical results have shown that the LUMO and HOMO energy levels of these dyes can be ensuring positive effect on the process of electron injection and dye regeneration. The trend of the calculated HOMO-LUMO gaps nicely compares with the spectral data. Key parameters in close connection with the short-circuit current density (Jsc), including light harvesting efficiency (LHE), injection driving force (?Ginject.) and total reorganization energy (?total), were discussed. The calculated results of these dyes reveal that dye D2, with indoline as electron donor group, can be used as a potential sensitizer for TiO2 nanocrystalline solar cells due to its best electronic and optical properties and good photovoltaic parameters.

Fitri, Asmae; Benjelloun, Adil Touimi; Benzakour, Mohammed; Mcharfi, Mohammed; Hamidi, Mohammed; Bouachrine, Mohammed

2014-11-01

39

Efficient degradation of organic dyes by BiAgxOy.  

PubMed

A novel, simple and efficient approach for degrading organic dye, based on BiAg(x)O(y) (bismuth silver oxide, BSO), is reported for the first time. The oxidative powder BSO was prepared by simple coprecipitation of NaBiO(3)·2H(2)O and AgNO(3). The technique was evaluated for the decolorization and oxidative decomposition of Rhodamine B (RhB). The results demonstrated that mixing BSO with an aqueous solution of RhB (20 mg/L) resulted in rapid decolorization (pseudo-first-order kinetic constant k=0.5594 min(-1)) and formation of several small molecular weight products. Significant reduction in TOC (32% TOC removal in 10 min) also occurred via mineralization of RhB to CO(2)/CO(3)(2-). The reaction proceeds at ambient temperature and pressure, and requires no external energy sources or light. An advantage of the technique is that BSO can be used to degrade sequential additions of dye without significant fouling or loss of activity. The characterization of BSO and its corrosion products by XRD, FTIR, TEM, EDX and XPS revealed that Ag species were reduced to metallic silver and NaBiO(3)·2H(2)O was transformed into the Bi(2)O(2)CO(3) during the reaction process. Singlet oxygen ((1)O(2)) was identified as the major reactive species generated by BSO for the degradation of RhB and several other dyes. This novel approach could be used as a highly efficient and green technology for organic dye degradation. PMID:22018868

Yu, Kai; Yang, Shaogui; Boyd, Stephen A; Chen, Hongzhe; Sun, Cheng

2011-12-15

40

Analysis of Dye Degradation Effects on Output Energy of the Pulsed Organic Dye Laser.  

National Technical Information Service (NTIS)

The dominant excitation and relaxation mechanisms found in dye molecules are discussed and then incorporated into a model for the xanthene dye laser. Rate equations for this model are presented which include terms that account for excited state singlet ab...

A. J. Bridging

1980-01-01

41

A multilayer organic electroluminescent device using an organic dye salt  

NASA Astrophysics Data System (ADS)

Organic electroluminescent devices have received considerable attention due to their application in flat-panel displays. To achieve full-color displays, it is necessary to obtain organic layers emitting red, green, and blue light, but it is still a challenge to obtain efficient and stable organic layer emitting red light so far. Recently, we found that an organic salt, trans-4-[p-[N-ethyl-N-(hydroxyethyl)amino]styryl]-N-methylphridinium tetraphenylborate (ASPT), exhibits efficient red-light emission. In this paper, we report a multilayer electrolumicescent device incorporating a hole-transport layer, an ASPT layer, and an electron-transport layer. The dependence of the carrier transport and the luminescence on the device structure is investigated in detail. Compared to the monolayer device, the balance between hole and electron injections is significantly improved for the multilayer device, and thus the electroluminescent efficiency and intensity are enhanced.

Feng, Xueyuan; Gu, Yongdi; Zhang, Jiayu; Cui, Yiping

2005-01-01

42

Interaction of protonated merocyanine dyes with amines in organic solvents  

NASA Astrophysics Data System (ADS)

2,6-Diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate ( 1a) and 4-[(1-methyl-4(1 H)-pyridinylidene)-ethylidene]-2,5-cyclohexadien-1-one ( 2a) were protonated in organic solvents (dichloromethane, acetonitrile, and DMSO) to form 1b and 2b, respectively. The appearance of the solvatochromic bands of 1a and 2a was studied UV-vis spectrophotometrically by deprotonation of 1b and 2b in solution in the presence of the following amines: aniline (AN), N-methylaniline (NMAN), N, N-dimethylaniline (NDAN), n-butylamine (BA), diethylamine (DEA), and triethylamine (TEA). Titrations of 1b and 2b with the amines were carried out and the binding constants were determined from the titration curves in each solvent, using a mathematical model adapted from the literature which considers the simultaneous participation of two dye: amine stoichiometries, 1:1 and 1:2. The data obtained showed the following base order for the two compounds in DMSO: BA > DEA > TEA, while aromatic amines did not cause any effect. In dichloromethane, the following base order for 1b was verified: TEA > DEA > BA ?NDAN, while for 2b the order was: TEA > DEA > BA, suggesting that 1b is more acidic than 2b. The data in acetonitrile indicated for 1b and 2b the following order for the amines: DEA > TEA > BA. The diversity of the experimental data were explained based on a model that considers the level of interaction of the protonated dyes with the amines to be dependent on three aspects: (a) the basicity of the amine, which varies according to their molecular structure and the solvent in which it is dissolved, (b) the molecular structure of the dye, and (c) the solvent used to study the system.

Ribeiro, Eduardo Alberton; Sidooski, Thiago; Nandi, Leandro Guarezi; Machado, Vanderlei Gageiro

2011-10-01

43

Interaction of protonated merocyanine dyes with amines in organic solvents.  

PubMed

2,6-Diphenyl-4-(2,4,6-triphenylpyridinium-1-yl)phenolate (1a) and 4-[(1-methyl-4(1H)-pyridinylidene)-ethylidene]-2,5-cyclohexadien-1-one (2a) were protonated in organic solvents (dichloromethane, acetonitrile, and DMSO) to form 1b and 2b, respectively. The appearance of the solvatochromic bands of 1a and 2a was studied UV-vis spectrophotometrically by deprotonation of 1b and 2b in solution in the presence of the following amines: aniline (AN), N-methylaniline (NMAN), N,N-dimethylaniline (NDAN), n-butylamine (BA), diethylamine (DEA), and triethylamine (TEA). Titrations of 1b and 2b with the amines were carried out and the binding constants were determined from the titration curves in each solvent, using a mathematical model adapted from the literature which considers the simultaneous participation of two dye: amine stoichiometries, 1:1 and 1:2. The data obtained showed the following base order for the two compounds in DMSO: BA>DEA>TEA, while aromatic amines did not cause any effect. In dichloromethane, the following base order for 1b was verified: TEA>DEA>BA?NDAN, while for 2b the order was: TEA>DEA>BA, suggesting that 1b is more acidic than 2b. The data in acetonitrile indicated for 1b and 2b the following order for the amines: DEA>TEA>BA. The diversity of the experimental data were explained based on a model that considers the level of interaction of the protonated dyes with the amines to be dependent on three aspects: (a) the basicity of the amine, which varies according to their molecular structure and the solvent in which it is dissolved, (b) the molecular structure of the dye, and (c) the solvent used to study the system. PMID:21802349

Ribeiro, Eduardo Alberton; Sidooski, Thiago; Nandi, Leandro Guarezi; Machado, Vanderlei Gageiro

2011-10-15

44

Effect of organic dyes on the dielectric properties of KH 2 PO 4 crystals  

Microsoft Academic Search

The effect of organic dyes on the dielectric properties of KH2PO4 (KDP) crystals is studied over a wide range of temperatures. The dielectric properties of KDP crystals doped with molecules\\u000a of the Chicago Sky Blue and Amaranth organic dyes are investigated for the first time. The dye molecules can be incorporated\\u000a into the crystal lattice of KDP and selectively paint

S. V. Grabovskii; I. V. Shnaidshtein; B. A. Strukov

2003-01-01

45

Catalytic degradation of organic dyes using biosynthesized silver nanoparticles.  

PubMed

The green synthesis of metallic nanoparticles paved the way to improve and protect the environment by decreasing the use of toxic chemicals and eliminating biological risks in biomedical applications. Plant mediated synthesis of metal nanoparticles is gaining more importance owing to its simplicity, rapid rate of synthesis of nanoparticles and eco-friendliness. The present article reports an environmentally benign and unexploited method for the synthesis of silver nanocatalysts using Trigonella foenum-graecum seeds, which is a potential source of phytochemicals. The UV-visible absorption spectra of the silver samples exhibited distinct band centered around 400-440 nm. The major phytochemicals present in the seed extract responsible for the formation of silver nanocatalysts are identified using FTIR spectroscopy. The report emphasizes the effect of the size of silver nanoparticles on the degradation rate of hazardous dyes, methyl orange, methylene blue and eosin Y by NaBH4. The efficiency of silver nanoparticles as a promising candidate for the catalysis of organic dyes by NaBH4 through the electron transfer process is established in the present study. PMID:24210247

Vidhu, V K; Philip, Daizy

2014-01-01

46

Case study on the destruction of organic dyes in supercritical water  

SciTech Connect

Organic dyes, which were used in Navy shells to mark ships and structures, need to be disposed of without burning. A study was undertaken to assess the feasibility of using supercritical water oxidation to destroy organic dyes. Experimental destruction efficiencies, product analyses, and process configuration are reported.

LaJeunesse, C.A.; Rice, S.F.

1994-11-01

47

Femtosecond spectroscopic study of carminic acid DNA interactions  

NASA Astrophysics Data System (ADS)

Photo-excited carminic acid and carminic acid-DNA complexes in a buffer solution at pH 7 have been examined using a variety of spectroscopy techniques, that are in particular, the femtosecond resolved fluorescence upconversion and transient absorption spectroscopy. The observation of dual fluorescence emission, one peaks at 470 nm and the other at 570 nm, indicates to an excited-state (S 1) intramolecular proton transfer (ESIPT). A detailed analysis of the transient absorption measurements of an aqueous carminic-acid solution at pH 7 yielded four lifetimes for the excited-state (S 1): 8, 15, 33 and 46 ps. On the other hand, only two lifetimes, 34 and 47 ps, were observed by fluorescence upconversion spectroscopy because of the detection limitation to the long wavelength edge of the carminic-acid spectrum. The four S 1 lifetimes were ascribed to the coexistence of respectively two tautomer (normal and tautomer) forms of carminic acid, in the non-dissociated state (CAH) and in the deprotonated state (CA -). The fluorescence upconversion measurements of carminic acid-DNA complexes exhibited a prolongation of the fluorescence lifetimes. This effect was accepted as evidence for the formation of intercalation complexes between the carminic acid and the DNA. The intercalative binding of the carminic acid to DNA was confirmed by the fluorescence titration experiments resulting to a binding constant of 2 × 10 5 M -1 that is typical for anthracycline-DNA complexes.

Comanici, Radu; Gabel, Bianca; Gustavsson, Thomas; Markovitsi, Dimitra; Cornaggia, Christian; Pommeret, Stanislas; Rusu, Catalin; Kryschi, Carola

2006-06-01

48

Photostability enhancement of anionic natural dye by intercalation into hydrotalcite  

Microsoft Academic Search

The aim of this study is the improvement of the photostability of several natural anionic dyes, carmine (CM), carthamus yellow (CY), and annatto dye (ANA), by complexation with hydrotalcite. The composite of the dyes and hydrotalcite is prepared by the coprecipitation method. CM is successfully intercalated in the hydrotalcite layer when the amount of introduced CM is large. The photostability

Yoshiumi Kohno; Koichi Totsuka; Shuji Ikoma; Keiko Yoda; Masashi Shibata; Ryoka Matsushima; Yasumasa Tomita; Yasuhisa Maeda; Kenkichiro Kobayashi

2009-01-01

49

Local tuning of organic light-emitting diode color by dye droplet application  

NASA Astrophysics Data System (ADS)

We have demonstrated that fluorescent dyes may be introduced into previously fabricated polymer thin films by local application of a dye-containing droplet. The UV fluorescence spectra of the films and the spectra of organic light-emitting diodes made from these films can be successfully tuned by this method. The technique has been implemented by ink-jet printing of the dye droplet.

Hebner, T. R.; Sturm, J. C.

1998-09-01

50

Analysis of dye degradation effects on output energy of the pulsed organic dye laser. Master's thesis  

SciTech Connect

The dominant excitation and relaxation mechanisms found in dye molecules are discussed and then incorporated into a model for the xanthene dye laser. Rate equations for this model are presented which include terms that account for excited state singlet absorption and triplet absorption. The system of rate equations are solved using the steady-rate approximation to derive equations for the threshold pump power and output power of the laser. The output power and threshold pump power equations are modified to include variables that allow the following effects of dye degradation to be examined: dye concentration reduction, reaction product absorption of pump radiation, reaction product absorption of lasing radiation, and singlet quenching by the reaction products. Theoretical values based on available experimental data are derived for these variables. A computer program is used to integrate the output power of the laser over the duration of a flashlamp pulse to compute the pulse energy.

Bridging, A.J.

1980-12-01

51

Efficient organic dye-sensitized solar cells: molecular engineering of donor-acceptor-acceptor cationic dyes.  

PubMed

Three metal-free donor-acceptor-acceptor sensitizers with ionized pyridine and a reference dye were synthesized, and a detailed investigation of the relationship between the dye structure and the photophysical and photoelectrochemical properties and the performance of dye-sensitized solar cells (DSSCs) is described. The ionization of pyridine results in a red shift of the absorption spectrum in comparison to that of the reference dye. This is mainly attributable to the ionization of pyridine increasing the electron-withdrawing ability of the total acceptor part. Incorporation of the strong electron-withdrawing units of pyridinium and cyano acrylic acid gives rise to optimized energy levels, resulting in a large response range of wavelengths. When attached to TiO2 film, the conduction band of TiO2 is negatively shifted to a different extent depending on the dye. This is attributed to the electron recombination rate between the TiO2 film and the electrolyte being efficiently suppressed by the introduction of long alkyl chains and thiophene units. DSSCs assembled using these dyes show efficiencies as high as 8.8?%. PMID:24039097

Cheng, Ming; Yang, Xichuan; Zhao, Jianghua; Chen, Cheng; Tan, Qin; Zhang, Fuguo; Sun, Licheng

2013-12-01

52

Controlling the bleeding of carmine colorant in crabstick.  

PubMed

Carmine used to color surimi seafood often seeps or bleeds from red-colored meat to white meat when vacuum-packed products go through high-temperature long-time pasteurization. Various physical and chemical treatments were examined to investigate means to inhibit or minimize carmine bleeding in surimi seafood products. Degree of bleeding was analyzed using L* (lightness) and a* (redness) as affected by carmine concentrations, pH, pasteurization conditions, and added calcium compounds. Bleeding was significantly affected by carmine concentrations. Optimum carmine concentration in color paste was 0.1%. Bleeding increased when pasteurization time and/or temperature increased. Color bleeding was also affected by moisture content of surimi paste. Carmine bleeding was minimized as pH of color solution decreased. The degree of bleeding was controlled as calcium compounds were added in color solution in a descending order of calcium chloride, calcium acetate, and calcium hydroxide. Minimal inhibition was obtained when color solutions contained calcium citrate, tricalcium phosphate, and calcium lactate. Practical Application: This manuscript addresses one of the long time problems in the surimi crabstick industry. Various means to control carmine bleeding or color transfer under high temperature for long time pasteurization were demonstrated. However, further study must continue to stop bleeding completely. PMID:20492104

Poowakanjana, Samanan; Park, Jae W

2009-01-01

53

Laser-Pumped Stimulated Emission from Organic Dyes: Experimental Studies and Analytic Comparisons.  

National Technical Information Service (NTIS)

Stimulated emission spectra of two organic dyes, chloro-aluminum phthalocyanine (CAP) and 3,3'-diethylthiatricarbocyanine iodide (DTTC) are compared. Giant-pulse ruby laser excitation was used in both cases. An end pumping configuration employed with DTTC...

P. P. Sorokin J. R. Lankard E. C. Hammond V. L. Moruzzi

1966-01-01

54

Pyrene-based organic dyes with thiophene containing ?-linkers for dye-sensitized solar cells: optical, electrochemical and theoretical investigations.  

PubMed

A new series of metal-free organic dyes containing pyrene and ?-cyanoacrylic acid end groups and thiophene, bithiophene, thienylbenzene or thienylfluorene ?-linkers were synthesized and characterized by absorption, emission and electrochemical measurements. Time-dependent density functional theoretical calculations were also performed to unravel the nature of the absorption induced electronic excitations. Extension of conjugation in the ?-linker by the incorporation of phenyl or fluorene was found to enhance the molar extinction coefficient while the use of thiophene red-shifted the absorption. The longer wavelength absorption peaks found for the dyes were attributed to ?-?* transition with a contribution from the charge transfer transition which becomes prominent for the bithiophene bridged derivative. The bithiophene containing dye showed moderate overall light-to-electron conversion efficiency attributable to the favorable absorption and redox properties originating due to the presence of a bithiophene segment. The trends observed for the various dyes in the device performance were rationalized by electron-impedance spectroscopy measurements. PMID:21879061

Baheti, Abhishek; Lee, Chuan-Pei; Thomas, K R Justin; Ho, Kuo-Chuan

2011-10-14

55

Photostimulated luminescence from CaS:Eu,Sm clusters embedded in organic dye  

NASA Astrophysics Data System (ADS)

The optical properties of rare-earth ions in an organic dye matrix have been studied because of their possible application for optical information storage. Strong IR photostimulated luminescence of CaS:Eu,Sm doped organic dye films was revealed in the sample prepared by the sol-gel method. It was found that the efficiencies of photostimulated luminescence in the CaS:Eu,Sm doped pyrazoline dye films are higher than that in the inorganic CaS:Eu,Sm materials. The grain size of the nanocrystallites, determined by X-ray diffraction, is approximately 50 nm. It was shown that the absorption spectra for organic dye films exhibit a remarkable anisotropy near a wavelength of 310 nm.

Kravets, V. G.; Kryuchin, A. A.; Ataev, V. A.; Shershukov, V. M.

2002-06-01

56

Influence of selected fluorescent dyes on small aquatic organisms  

NASA Astrophysics Data System (ADS)

Rhodamine B and Rhodamine WT are fluorescent dyes commonly used as tracers in hydrological investigations. Since introducing intensely red substances into rivers raises understandable doubts of ecological nature, the authors aimed at examining the influence of these dyes on small water fauna using bioindication methods. Quantitative results, calculated with the use of Bliss-Weber probit statistical method, were achieved by means of standardized ecotoxicological tests containing ready-to-hatch resting forms of fairy shrimp ( Thamnocephalus platyurus). Qualitative studies included observation of water flea crustacean ( Daphnia magna) and horned planorbis snail ( Planorbis corneus), both typically present in rivers and representative for temperate climate, as well as guppy fish ( Poecilla reticulata), paramecium protozoan ( Paramaecium caudatum) and the above-mentioned fairy shrimp. The investigation revealed that both dyes in concentrations used for hydrological purposes are low enough to exert almost no toxic impact on water fauna considered.

Rowi?ski, Pawe? M.; Chrzanowski, Marcin M.

2011-02-01

57

The function of a TiO2 compact layer in dye-sensitized solar cells incorporating "planar" organic dyes.  

PubMed

We present a device based study into the operation of liquid electrolyte dye-sensitized solar cells (DSSC's) using organic dyes. We find that, for these systems, it is entirely necessary to employ a compact TiO2 layer between the transparent fluorine doped SnO2 (FTO) anode and the electrolyte in order to reduce charge recombination losses. By incorporation of a compact layer, the device efficiency can be increased by over 160% under simulated full sun illumination and more than doubled at lower light intensities. This is strong evidence that the more widely employed ruthenium based sensitizers act as to "insulate" the anode against recombination losses and that many planar organic dyes employed in DSSC's could greatly benefit from the use of a compact TiO2 blocking layer. This is in strong contrast to DSSC's sensitized with ruthenium based systems, where the introduction of compact TiO2 has only marginal effects on conversion efficiencies. PMID:18318506

Burke, Anthony; Ito, Seigo; Snaith, Henry; Bach, Udo; Kwiatkowski, Joe; Grätzel, Michael

2008-04-01

58

HPLC–DAD–MS analysis of dyes identified in textiles from Mount Athos  

Microsoft Academic Search

Organic colorants contained in 30 textiles (16th to early 20th century) from the monastery of Simonos Petra (Mount Athos)\\u000a have been investigated using high-performance liquid chromatography equipped with diode-array detection and mass spectrometry\\u000a (HPLC–DAD–MS). The components of natural dyes identified in samples treated by the standard HCl dyestuff extraction method\\u000a were: alizarin, apigenin, butein, carminic acid, chrysoeriol, dcII, dcIV, dcVII,

Dimitrios Mantzouris; Ioannis Karapanagiotis; Lemonia Valianou; Costas Panayiotou

2011-01-01

59

Organic dyes in PMMA in a planar luminescent solar collector: a performance evaluation.  

PubMed

The performance of organic dyes in PMMA has been evaluated in a three-layer planar luminescent solar concentrator. The single plate and combined three-plate efficiencies have been measured for a number of dyes, and results of one typical combination are reported here. A detailed characterization of the spectroscopic properties of the dye molecules as well as the device dependent and device independent parameters of the plates allow comparison between measured and predicted efficiency. Our results demonstrate the presence of a significant positive synergism for the multilayer device. PMID:20396154

Drake, J M; Lesiecki, M L; Sansregret, J; Thomas, W R

1982-08-15

60

Synthesis and Characterization of Organic Dyes Containing Various Donors and Acceptors  

PubMed Central

New organic dyes comprising carbazole, iminodibenzyl, or phenothiazine moieties, respectively, as the electron donors, and cyanoacetic acid or acrylic acid moieties as the electron acceptors/anchoring groups were synthesized and characterized. The influence of heteroatoms on carbazole, iminodibenzyl and phenothiazine donors, and cyano-substitution on the acid acceptor is evidenced by spectral, electrochemical, photovoltaic experiments, and density functional theory calculations. The phenothiazine dyes show solar-energy-to-electricity conversion efficiency (?) of 3.46–5.53%, whereas carbazole and iminodibenzyl dyes show ? of 2.43% and 3.49%, respectively.

Wu, Tzi-Yi; Tsao, Ming-Hsiu; Chen, Fu-Lin; Su, Shyh-Gang; Chang, Cheng-Wen; Wang, Hong-Paul; Lin, Yuan-Chung; Ou-Yang, Wen-Chung; Sun, I-Wen

2010-01-01

61

Studies of the photoelectrochemistry of organic dyes using attenuated total reflection techniques  

SciTech Connect

An experimental apparatus has been assembled for the photoelectrochemical investigation of organic dyestuffs: through the use of attenuated total reflection (ATR) techniques, it is capable of measuring photocurrent, dye absorbance, and fluorescence simultaneously in computer controlled experiments with a time resolution of 200 nsec. Selected semiconductors have been cut and polished to the prismatic shape required of the substrate electrode. The spectral and energetic characteristics of several series of cyanine dyes have been determined; their photoelectrochemical behavior has been studied using standard techniques prior to use in the ATR system. Experimentation with these dyes in the ATR arrangement is now in progress.

Spitler, M.T.

1981-01-01

62

Molecular interaction of organic dyes in bulk and confined media  

NASA Astrophysics Data System (ADS)

Molecular interactions of five thiazine dyes with increasing alkyl substitution have been studied in aqueous and microemulsion media at 303 K within a concentration range of (1.35-7.00) × 10 -4 M. The dimerization constant ( Kd) values for the five dyes are ranged between 1.761 and 6.258 × 10 3 l mol -1 in bulk water media, where as in microemulsion media, Kd's are ranged between 1.760 and 4.110 × 10 3 l mol -1. Thionine (with no methyl substitution) and azure A (with two methyl substitution) displayed slightly larger Kd values in microemulsion water pools compared to bulk water while other dyes recorded significant drop in Kd values. The influence of microemulsion media on the molecular interaction of dyes has been explained in terms of electrostatic and hydrophobic factors. The monomer and the dimer spectra are explained in terms of molecular exciton model and the optical absorption parameters of both the species are reported in bulk and confined media.

Chakraborty, Amitabha; Ali, Moazzam; Saha, Swapan K.

2010-05-01

63

Energy level alignment in metal\\/oxide\\/semiconductor and organic dye\\/oxide systems  

Microsoft Academic Search

The alignment between the energy levels of the constituent materials of metal-oxide-semiconductor field effect transistors (MOSFET's) and dye sensitized solar cell (DSSC's) is a key property that is critical to the functions of these devices. We have measured the energy level alignment (band offsets) for metal\\/oxide\\/semiconductor (MOS) systems with high-kappa gate oxides and metal gates, and for organic dye\\/oxide systems.

Eric Bersch

2008-01-01

64

Dye-sensitized photoelectrochemical solar cells based on nanocomposite organic–inorganic materials  

Microsoft Academic Search

Dye-sensitized photoelectrochemical solar cells have been constructed by using nanocomposite organic–inorganic sol–gel electrolytes and a titania nanocrystalline film also based on a sol–gel nanocomposite material. Among other advantages connected with nanocomposite electrolytes is the balance between hydrophilic and hydrophobic domains that allows reducing polarity-connected repulsive forces developing between the titania-dye system and the electrolyte. The overall efficiencies of these cells

Elias Stathatos; Panagiotis Lianos; Vasko Jovanovski; Boris Orel

2005-01-01

65

Solubilization of two organic dyes by cationic ester-containing gemini surfactants.  

PubMed

Solubilization of two different types of organic dyes, Quinizarin with an anthraquinone structure and Sudan I with an azo structure, has been studied in aqueous solutions of a series of cationic gemini surfactants and of a conventional monomeric cationic surfactant, dodecyltrimethylammonium bromide (DTAB). Surfactant concentrations both above and below the critical micelle concentration were used. The concentration of solubilized dye at equilibrium was determined from the absorbance of the solution at ?(max) with the aid of a calibration curve. The solubilization power of the gemini surfactants was higher than that of DTAB and increased with increasing alkyl chain length. An increase in length of the spacer unit resulted in increased solubilization power while a hydroxyl group in the spacer did not have much effect. Ester bonds in the alkyl chains reduced the solubilization power with respect to both dyes. A comparison between the absorbance spectra of the dyes in micellar solution with spectra in a range of solvents of different polarity indicated that the dye is situated in a relatively polar environment. One may therefore assume that the dye is located just below the head group region of the micelle. Attractive ?-cation interactions may play a role for orienting the dye to the outer region of the micelle. PMID:22444485

Tehrani-Bagha, A R; Singh, R G; Holmberg, K

2012-06-15

66

Electrophoretic deposition of TiO2 nanoparticles using organic dyes.  

PubMed

Electrophoretic deposition method has been developed for the deposition of TiO(2) nanoparticles modified with organic dyes. Alizarin red, alizarin yellow and pyrocatechol violet dyes were used for the dispersion and charging of TiO(2) in ethanol and anodic electrophoretic deposition of TiO(2) films. The deposition yield was varied by the variation of dye concentration in suspensions and deposition time. Aurintricarboxylic acid dye was used for the deposition of TiO(2) from aqueous suspensions. It was found that thin films of pure aurintricarboxylic acid and composite aurintricarboxylic acid TiO(2) films can be obtained. The deposition yield was studied by quartz crystal microbalance. Dye film thickness was varied in the range of 0.1-2 ?m by variation in the deposition time at a constant voltage. The composition of the films and the amount of the deposited material can be varied by the variation of TiO(2) and dye concentration in suspensions and deposition time. The films were studied by Fourier transform infrared spectroscopy, thermogravimetric analysis, differential thermal analysis and electron microscopy. The deposition mechanisms were discussed. The electrophoretic deposition method offers advantages for the fabrication of dye-sensitized TiO(2) films. PMID:22204967

Sun, Y; Ata, M S; Zhitomirsky, I

2012-03-01

67

Ablative optical recording using organic dye-in-polymer films  

NASA Astrophysics Data System (ADS)

Ablative optical recording using dissolved dyes in polymer films has been investigated. Polyester yellow dissolved in poly(vinyl acetate) was used as a model to study the potential for high-sensitivity, high-density optical storage applications. With 20% dye loading, a 59-nm film was more sensitive at 457 nm than a 15-nm Te monolayer, and marks down to 0.5 ?m were recorded. The signal contrast (Rf-Ri)/(Rf+Ri) was approximately 0.68 for marks ablated with high-energy laser pulses. The morphology of the marks shows a clean removal of recording material. Suitable polymeric overcoatings, used to simulate second-surface recording situations, had little effect on the results.

Law, K. Y.; Vincett, P. S.; Loutfy, R. O.; Alexandru, L.; Hopper, M. A.; Sharp, J. H.; Johnson, G. E.

1980-06-01

68

Eucalyptus bark powder as an effective adsorbent: Evaluation of adsorptive characteristics for various dyes  

Microsoft Academic Search

Dyes are usually present in trace quantities in the treated effluents of many industries. This study investigates the potential use of Eucalyptus bark powder (EBP) as an adsorbent for adsorption of industrially important dyes namely malachite green, indigo carmine and methylene blue from wastewater. The operating variables studied are initial dye concentration, pH, temperature and contact time. It was noted

Ruchi Srivastava; D. C. Rupainwar

2009-01-01

69

A method for concentrating organic dyes: colorimetric measurements of nitric oxides and sialic acids.  

PubMed

A new method for extraction and concentration of organic dyes that uses a reagent composed of a nonionic detergent mixed with an alcohol is described. We have observed that water-soluble organic dyes are also soluble in nonionic detergents and can be extracted by adding salt, which separates the dye-detergent component from the aqueous phase. We have also found that mixing nonionic detergents with alcohols markedly reduces their viscosity and produces stable, free-flowing, and effective reagents for color extraction. On the basis of these observations, we used a mixture of Triton X-100 and 1-butanol and observed that water-soluble natural and synthetic chromophores, as well as dyes generated in biochemical reactions, can be extracted, concentrated, and analyzed spectrophotometrically. Trypan blue and phenol red are used as examples of synthetic dyes, and red wine is used as an example of phenolic plant pigments. Applications for quantification of nitric oxides and sialic acids are described in more detail and show that as little as 0.15 nmol of nitric oxide and 0.20 nmol of sialic acid can be detected. A major advantage of this method is its ability to concentrate chromophores from dye-containing solutions that otherwise cannot be measured because of their low concentrations. PMID:21605540

Lalezari, Parviz; Lekhraj, Rukmani; Casper, Diana

2011-09-01

70

Singlet oxygen generation from water-soluble quantum dot-organic dye nanocomposites.  

PubMed

Water-soluble quantum dot-organic dye nanocomposites have been prepared via electrostatic interaction. We used CdTe quantum dots with diameters up to 3.4 nm, 2-aminoethanethiol as a stabilizer, and meso-tetra(4-sulfonatophenyl)porphine dihydrochloride (TSPP) as an organic dye. The photophysical properties of the nanocomposite have been investigated. The fluorescence of the parent CdTe quantum dot is largely suppressed. Instead, indirect excitation of the TSPP moiety leads to production of singlet oxygen with a quantum yield of 0.43. The nanocomposite is sufficiently photostable for biological applications. PMID:16683767

Shi, Lixin; Hernandez, Billy; Selke, Matthias

2006-05-17

71

The role of rare earth oxide nanoparticles in suppressing the photobleaching of fluorescent organic dyes  

NASA Astrophysics Data System (ADS)

Organic dyes are widely used for both industrial as well as in scientific applications such as the fluorescent tagging of materials. However the process of photobleaching can rapidly degrade dye fluorescence rendering the material non-functional. Thus exploring novel methods for preventing photobleaching can have widespread benefits. In this work we show that the addition of minute quantities of rare earth (RE) oxide nanoparticles can significantly suppress the photobleaching of dyes. The fluorescence of Rhodamine and AlexaFluor dyes was measured as a function of time with and without the addition of CeO2 and La2O3 nanoparticle additives (two RE oxides that contain an oxygen vacancy based defect structure), as well as with FeO nanoparticles (which has an oxygen excess stoichiometry). We find that the rare earth oxides significantly prolonged the lifetimes of the dyes. The results allow us to develop a model based upon the presence of oxygen vacancies defects that allow the RE oxides to act as oxygen scavengers. This enables the RE oxide particles to effectively remove reactive oxygen free radicals generated in the dye solutions during the photoabsorption process.

Guha, Anubhav; Basu, Anindita

2013-03-01

72

Active polymer fibres doped with organic dyes: Generation and amplification of coherent radiation  

SciTech Connect

The technology is developed for manufacturing active polymer optical fibres doped with organic dyes. Stimulated emission and amplification in the long-wavelength part of the visible spectrum is studied for rhodamine 11B, phenalemine 512 and substituted DCM pyran in polymer optical fibres. Lasing was observed upon longitudinal and transverse pumping by the second harmonic of a Nd:YAG laser. The gain in polymer fibres was estimated by measuring the intensity ratio of radiation of a master oscillator (dye laser) propagated through the excited (pumped) and unexcited (not pumped) fibre pieces doped with organic dyes. It is shown that the lasing efficiency of rhodamine 11B in a transversely pumped polymer fibre can achieve 36%. The maximum gain (25 dB m{sup -1}) is obtained in fibres doped with phenalemine 512. (lasers)

Maier, G V; Kopylova, T N; Svetlichnyi, Valerii A [V.D. Kuznetsov Siberian Physical-Technical Institute, Tomsk (Russian Federation); Podgaetskii, Vitalii M [Moscow Institute of Electronic Engineering (Technical University), Moscow (Russian Federation); Dolotov, S M; Ponomareva, O V [Deltacor Limited Liability Company, Dolgoprudnyi, Moscow Region (Russian Federation); Monich, A E; Monich, E A [Impulse Scientific and Technical Center, Krasnodarskii krai, Apsheronsk (Russian Federation)

2007-01-31

73

Organic fluorescent thermometers based on borylated arylisoquinoline dyes.  

PubMed

Borylated arylisoquinolines with redshifted internal charge-transfer (ICT) emission were prepared and characterized. Upon heating, significant fluorescence quenching was observed, which forms the basis for a molecular thermometer. In the investigated temperature range (283-323?K) an average sensitivity of -1.2 to -1.8?%?K(-1) was found for the variations in fluorescence quantum yield and lifetime. In the physiological temperature window (298-318?K) the average sensitivity even reaches values of up to -2.4?%?K(-1) . The thermometer function is interpreted as the interplay between excited ICT states of different geometry. In addition, the formation of an intramolecular Lewis pair can be followed by (11) B?NMR spectroscopy. This provides a handle to monitor temperature-dependent ground-state geometry changes of the dyes. The role of steric hindrance is addressed by the inclusion of a derivative that lacks the Lewis pair formation. PMID:24861774

Pais, Vânia F; Lassaletta, José M; Fernández, Rosario; El-Sheshtawy, Hamdy S; Ros, Abel; Pischel, Uwe

2014-06-16

74

Comparative efficiency of energy transfer from CdSe-ZnS quantum dots or nanorods to organic dye molecules.  

PubMed

Fluorescence resonance energy transfer (FRET) in conjugates of CdSe-ZnS semiconductor nanocrystals of different shapes (FRET donors) and an Alexa Fluor organic dye (FRET acceptors) is examined. The dye molecules are chemically conjugated with quantum dots (QDs) or nanorods (NRs) in dimethyl sulfoxide colloidal solutions, and FRET efficiency in the purified conjugates is measured. The FRET from NR to a single dye molecule is less efficient than that of the QD-dye conjugates and this effect is explained in terms of distance-limited energy-transfer rate in the case of a point-like acceptor and extended donor dipoles. However, the larger surface area of NRs allows for many more dye acceptors to be bound, and the total FRET efficiency in NR-dye conjugates approaches those of QD-dye conjugates. PMID:22228648

Hardzei, Marya; Artemyev, Mikhail; Molinari, Michael; Troyon, Michel; Sukhanova, Alyona; Nabiev, Igor

2012-01-16

75

Photocatalytic Destruction of an Organic Dye Using TiO2 and Solar Energy.  

ERIC Educational Resources Information Center

Describes a general chemistry experiment that is carried out in sunlight to illustrate the ability of TiO2 to act as a photocatalyst by mineralizing an organic dye into carbon dioxide. Details about the construction of the reactor system used to perform this experiment are included. (DDR)

Giglio, Kimberly D.; And Others

1995-01-01

76

Performance measurement of dye-sensitized solar cells and organic polymer solar cells  

Microsoft Academic Search

Performance characterization of the dye-sensitized solar cells (DSC) and organic polymer solar cells (OSC) has been investigated, in order to clarify how to accurately determine their performance. Accurate characterization of DSC requires consideration on the very slow temporal response, and variation of the quantum efficiency spectrum for the bias light. The I-V curves of the DSC are clearly dependent on

Yoshihiro Hishikawa

2008-01-01

77

Optical Properties of Fluorescent Mixtures: Comparing Quantum Dots to Organic Dyes  

ERIC Educational Resources Information Center

The study describes and compares the size-dependent optical properties of organic dyes with those of semiconductor nanocrystals or quantum dots (QDs). The analysis shows that mixtures of QDs contain emission colors that are sum of the individual QD components.

Hutchins, Benjamin M.; Morgan, Thomas T.; Ucak-Astarlioglu, Mine G.; Wlilliams, Mary Elizabeth

2007-01-01

78

Rhodanine dye-based small molecule acceptors for organic photovoltaic cells.  

PubMed

The solution-processable small molecules based on carbazole or fluorene containing rhodanine dyes at both ends were synthesized and introduced as acceptors in organic photovoltaic cells. The high energy levels of their lowest unoccupied molecular orbitals resulted in a power conversion efficiency of 3.08% and an open circuit voltage of up to 1.03 V. PMID:24934612

Kim, Yujeong; Song, Chang Eun; Moon, Sang-Jin; Lim, Eunhee

2014-07-01

79

Design issues for improved environmental performance of dye-sensitized and organic nanoparticulate solar cells  

Microsoft Academic Search

Though environmental improvement has been claimed for the application of nanotechnology to solar cells, several characteristics of the fullerene-based organic, and the dye-sensitized nanoparticulate, solar cell are not conducive to such improvement. These include relatively high energy and materials inputs in the production of nanoparticles, a relatively low solar radiation to electricity conversion efficiency, a relatively short service life, the

L. Reijnders

2010-01-01

80

Organization of butadienyl dyes containing benzodithiacrown-ether or dimethoxybenzene in monolayers at the air/aqueous salt solution interface.  

PubMed

Two amphiphilic butadienyl dyes 1 and 2 form stable monolayers at the air/water interface in the presence of various salts. Dye 1 consists of the basic amphiphilic butadienyl chromophore. In dye 2, the dimethoxybenzene part of dye 1 is substituted by benzodithia-15-crown-5. The monolayers have been characterized by surface pressure-area and surface potential-area isotherms as well as Brewster angle microscopy and reflection spectroscopy. In contrast to dye 1, dye 2 interacts specifically with Hg(2+) and Ag(+) cations forming complexes. No complex formation was observed with alkali and earth alkali metal ions. The nature of the anion (Cl(-) or ClO(4)(-)) influences the monolayer behaviour of both dyes. At the air/water interface, besides monomers of the dyes, two types of associates are coexisting in the pure dye monolayers on aqueous salt solutions, attributed to dimers and aggregates, respectively. Their equilibria depend on the nature of both cations and anions in the subphase, as in the case of dye 2, or only anions, as in the case of dye 1. The dimers may be organized as head-to-tail dimers with the intermolecular distances 0.38 and 0.45nm for dye 1 and dye 2, respectively. According to the extended dipole model, we propose formation of aggregates in which the chromophores are parallel to each other with the same intermolecular distances as in the dimers, and the centers of their transition moments shifted by 0.95nm (dye 1) and 1.2nm (dye 2). PMID:19720508

Sergeeva, T I; Gromov, S P; Zaitsev, S Yu; Möbius, D

2009-12-01

81

Effect of enzymatic treatment on the dyeing of cotton and wool fibres with natural dyes  

Microsoft Academic Search

Cotton and wool fabrics were dyed with the natural dyes chlorophyll and carmine after treatment with the enzymes cellulase, ?-amylase and trypsin. Wash and light fastnesses of the dyed samples were studied. Enzymatic pretreatment resulted in an increase in pigment uptake in all cases compared with the corresponding untreated samples, and did not affect fastness properties. Pretreatment with metallic salts

E. Tsatsaroni; M. Liakopoulou-Kyriakides

1995-01-01

82

Carbazole-Dendrimer-Based Donor-?-Acceptor Type Organic Dyes for Dye-Sensitized Solar Cells: Effect of the Size of the Carbazole Dendritic Donor.  

PubMed

A series of novel D-?-A type organic dyes, namely, GnTA (n = 1-4), containing carbazole dendrons up to fourth generation as a donor, bithiophene as ?-linkage, and cyanoacrylic acid as acceptor were synthesized and characterized for applications in dye-sensitized solar cells (DSSCs). The photophysical, thermal, electrochemical, and photovoltaic properties of the new dyes as dye sensitizers were investigated, and the effects of the carbazole dendritic donors on these properties were evaluated. Results demonstrated that increasing the size or generation of the carbazole dendritic donor of the dye molecules enhances their total light absorption abilities and unluckily reduces the amount of dye uptake per unit TiO2 area because of their high molecular volumes. The latter was found to have a strong effect on the power conversion efficiency of DSSCs. Importantly, electrochemical impedance spectroscopy (EIS) revealed that the size or generation of the donor had a significant influence on a charge-transfer resistance for electron recombination at the TiO2/electrolyte interface, causing a difference in open circuit voltage (Voc) of the solar cells. Among them, dye G1TA containing first generation dendron as a donor (having lowest molecular volume) exhibited the highest power conversion efficiency of 5.16% (Jsc = 9.89 mA cm(-2), Voc = 0.72 V, ff = 0.73) under simulated AM 1.5 irradiation (100 mW cm(-2)). PMID:24878449

Thongkasee, Pongsathorn; Thangthong, Amonrat; Janthasing, Nittaya; Sudyoadsuk, Taweesak; Namuangruk, Supawadee; Keawin, Tinnagon; Jungsuttiwong, Siriporn; Promarak, Vinich

2014-06-11

83

Computational comparison of CPDT to other conjugated linkers in triarylamine-based organic dyes.  

PubMed

The use of the cyclopentadithiophene (cpdt) fragment to chemically link electron donor and acceptor groups has become a rather common procedure to design new organic dyes with enhanced light harvesting properties. The photo-to-current efficiencies obtained by sensitized solar cells with dyes incorporating the cpdt moiety are commonly improved with respect to other similar ?-fragments as separators. In many cases, the advantages of cpdt can be related to the larger extinction coefficients obtained. In this work we perform a detailed computational study of triarylamine-based organic dyes with the cyanoacrylic acid as the acceptor group and considering a variety of conjugated linkers with cpdt as the reference case. The influence of slightly different linkers and donor groups in the computed excitation energies and oscillator strengths is discussed by means of molecular geometries and frontier orbitals. The structural characteristics imposed by cpdt compared to similar conjugated bridges are responsible for its larger computed oscillator strengths. The insertion of an ethylene unit between the donor group and the linker systematically reduces the energy gap to the first excited singlet state and yields larger oscillator strengths of the optical transition. These results could be very helpful in the quest of new organic dyes with improved properties as sensitizers in Grätzel cells. PMID:23574949

Climent, Clàudia; Casanova, David

2013-01-01

84

Pure red emission of dye-doped organic molecules from microcavity organic light emitting diode  

NASA Astrophysics Data System (ADS)

Organic red emitting diode was fabricated by using 4-dicyanomethylene-2-methyl-6-[2-(2,3,6,7-tetrahydro-1 H,5H-benzo[ij]quinolizin-8-yl)vinyl]-4H-pyran (DCM)-doped tri-(8-quinolitolato) aluminum (Alq 3) as emitter with the structure of G/ITO/NPB(25 nm)/DCM:Alq 3(55 nm)/Alq 3(20 nm)/LiF (1.2 nm)/Al(84 nm), (glass/indium-tin-oxide/4,4- bis-[ N-(1-naphthyl)- N-phenyl-amino]biphenyl, G/ITO/NPB), the wavelength of the maximal emission of which is 615 nm. By introducing cavity to Organic light emitting diode (OLED), we got pure red emitting diode with wavelength of the maximal emission of 621 nm and full-width at half-maximum (FWHM) of 27 nm. As far as we know, it is the best result in the dye-doped organic red emitting diode. We also made a device of G/ITO/NPB(25 nm)/DCM:Alq 3(29 nm)/DCM:PBD(26 nm)/Alq 3(20 nm)/LiF(1.2 nm)/Al(84 nm), in order to compare the performance of Alq 3 with that of 2-(4-biphenylyl)-5-(4- t-butylphenyl)-1,3,4-oxadiazole (PBD) as host material. It was found that the performance of device A is better than that of C both in brightness and color purity,as well as in EL efficiency.

Cheng, Dong-ming; Ma, Feng-ying; Liu, Xing-yuan

2007-06-01

85

Intermolecular interactions between a Ru complex and organic dyes in cosensitized solar cells: a computational study.  

PubMed

Intermolecular interactions in cyclometalated Ru complex dye (FT89) dimers, carbazole organic dye (MK-45 and MK-111) dimers, FT89-MK-45 complexes, and FT89-MK-111 complexes were investigated using density functional theory (DFT) and time-dependent DFT (TD-DFT) to elucidate the improvement mechanism of dye-sensitized solar cell (DSSC) performance due to cosensitization with FT89 and MK dyes. All of the dimers and complexes form intermolecular cyclic hydrogen bonds via the carboxyl groups. The FT89 dimer and complexes with the TiO2Na model system promote intermolecular interactions with I2via the NCS ligand of the FT89 monomer. The computational results verify that MK-111 behaves not only as a sensitizer but also inhibits FT89 aggregation by effectively serving as a coadsorbent similar to deoxycholic acid (DCA) in the dye solution, suppressing recombination of the injected electrons in TiO2 with I2, improving DSSC performance. PMID:24968132

Kusama, Hitoshi; Funaki, Takashi; Koumura, Nagatoshi; Sayama, Kazuhiro

2014-07-01

86

Quantum dynamics simulations of interfacial charge-transfer in organic dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

We describe a novel time-dependent quantum-mechanics/molecular-mechanics method for studying electron transfer in dye sensitized semiconductor interfaces, that takes into account the interacting electron-hole quantum dynamics, the underlying nuclear fluctuations and solvation dynamics. We provide a comprehensive investigation of the quantum dynamics, the electronic and the structural properties of prototypical D-?-A organic dyes sensitizing the TiO2 anatase surface, both in vacuum and solvated by liquid acetonitrile. The organic dyes are comprised of an electron donating moiety and an anchoring acceptor moiety, conjugated by thiophene bridges. Although interfacial electron transfer is very efficient, it is demonstrated that the coupling between the photoexcited electron and the hole delays the electron injection. Simulations demonstrate that the solvent screens the dye from the surface, narrowing the absorption peaks and delaying the electron injection. We have also studied several aspects that are relevant for the recombination process, such as the role played by surface defects and the interaction of redox species with the TiO2 surface, and the effect of additives.

Rego, Luis G. C.; da Silva, R.; Hoff, D. A.

2013-03-01

87

Third-order nonlinear optical response of indigo carmine under 633 nm excitation for nonlinear optical applications  

NASA Astrophysics Data System (ADS)

We report thermally induced third-order nonlinearity and optical limiting behaviour of Indigo Carmine dye. z-Scan technique was used to determine the sign and magnitude of absorptive and refractive nonlinearities. Continuous wave (CW) He-Ne laser operating at 633 nm was used as source of excitation. In open aperture z-scan experiments, samples exhibited reverse saturable absorption (RSA) process. For closed aperture z-scan experiments, samples revealed self-defocusing property. The presence of donor and acceptor groups in the structure increases the conjugation length and in turn increases the optical nonlinearity. Induced self-diffraction rings pattern was recorded for the samples and it is attributed to refractive index change and thermal lensing. Also, optical limiting and clamping studies were carried out for various input power. Optical clamping of about ~1 mW was observed. This endorses that the dye under investigation is a positive candidate for opto-electronic and photonic applications.

Pramodini, S.; Poornesh, P.

2014-11-01

88

Blue natural organic dyestuffs--from textile dyeing to mural painting. Separation and characterization of coloring matters present in elderberry, logwood and indigo.  

PubMed

Natural dyestuffs used for painting or dyeing of textiles are complex mixtures of compounds of various chemical properties. Proper identification of the dye used by a painter and, even better, its origin is possible only when its compositional 'fingerprint' can be evaluated. For this reason gradient program for liquid chromatographic separation of 16 color compounds--components of natural blue dyes: elderberry, logwood and indigo--has been developed. Two detector systems were used simultaneously: UV-Vis spectrophotometry (at 280, 445, 520 and 600 nm) and ESI mass spectrometry (positive and negative SIM mode). It was found that fragmentation observed in ESI-MS is affected not only by ion source parameters, but also by chromatographic conditions, especially in case of the less stable substances: cyanidin glucosides, tannic acid, rutin and hematoxylin. Examination of characteristic dissociation pathways of the compounds under investigation after direct admission into ion source or after chromatographic separation allowed to select proper ions for SIM detection and to develop novel and efficient reversed phase high performance liquid chromatographic (RP-HPLC)-UV-Vis/ESI-MS method for the analysis of natural blue dyes. The procedure was successfully applied for identification of indigotin and carminic acid-main colorants extracted from a fiber taken from the blue-red 'Italian' tapestry (the collection of the National Museum in Warsaw, Poland). PMID:16575781

Pawlak, Katarzyna; Puchalska, Maria; Miszczak, Agata; Ros?oniec, Elzbieta; Jarosz, Maciej

2006-05-01

89

Adsorption of organic dyes on TiO2 surfaces in dye-sensitized solar cells: interplay of theory and experiment.  

PubMed

First-principles computer simulations can contribute to a deeper understanding of the dye/semiconductor interface lying at the heart of Dye-sensitized Solar Cells (DSCs). Here, we present the results of simulation of dye adsorption onto TiO(2) surfaces, and of their implications for the functioning of the corresponding solar cells. We propose an integrated strategy which combines FT-IR measurements with DFT calculations to individuate the energetically favorable TiO(2) adsorption mode of acetic acid, as a meaningful model for realistic organic dyes. Although we found a sizable variability in the relative stability of the considered adsorption modes with the model system and the method, a bridged bidentate structure was found to closely match the FT-IR frequency pattern, also being calculated as the most stable adsorption mode by calculations in solution. This adsorption mode was found to be the most stable binding also for realistic organic dyes bearing cyanoacrylic anchoring groups, while for a rhodanine-3-acetic acid anchoring group, an undissociated monodentate adsorption mode was found to be of comparable stability. The structural differences induced by the different anchoring groups were related to the different electron injection/recombination with oxidized dye properties which were experimentally assessed for the two classes of dyes. A stronger coupling and a possibly faster electron injection were also calculated for the bridged bidentate mode. We then investigated the adsorption mode and I(2) binding of prototype organic dyes. Car-Parrinello molecular dynamics and geometry optimizations were performed for two coumarin dyes differing by the length of the ?-bridge separating the donor and acceptor moieties. We related the decreasing distance of the carbonylic oxygen from the titania to an increased I(2) concentration in proximity of the oxide surface, which might account for the different observed photovoltaic performances. The interplay between theory/simulation and experiments appears to be the key to further DSCs progress, both concerning the design of new dye sensitizers and their interaction with the semiconductor and with the solution environment and/or an electrolyte upon adsorption onto the semiconductor. PMID:23108504

Anselmi, Chiara; Mosconi, Edoardo; Pastore, Mariachiara; Ronca, Enrico; De Angelis, Filippo

2012-12-14

90

Plant toxic and non-toxic nature of organic dyes through adsorption mechanism on cellulose surface.  

PubMed

Effluents releasing from dyeing industries directly affect the soil, water, plant and human life. Among these dyes, plant poisoning, soil polluting and water polluting nature of organic dyes are not yet identified. The plant poisoning and non-poisoning organic dyes are identified through adsorption mechanism of cationic malachite green (MG) and anionic methyl orange (MO) on brinjal plant root powder (cellulose). The positive ?H(o) (44 kJ mol(-1)) of MG higher than 40 kJ mol(-1) confirmed the adsorption of MG on cellulose is chemisorption and the negative ?H(o) (-11 kJ mol(-1)) less than 40 kJ mol(-1) showed that the adsorption of MO on cellulose is physisorption. The ?G(o) values for the adsorption of MG and MO on BPR are not much increased with increase of temperature which indicated that the adsorption is independent of the temperature. The entropy change for the adsorption of MG and MO has proved that the MG (+?S(o)) has less disorder at the adsorption interface and MO (-?S(o)) has the high disorder at the adsorption interface. The recovery of both dyes has been studied in water at 80°C on BPR surface and observed that the MO recovery is 95% and MG is 10%. The poor desorption of MG is due to the strong chemisorption on BPR (cellulose) surface proves its plant poisoning nature. The high recovery of MO due to physisorption mechanism proves that MO is not poisoning the plant. PMID:21398036

Buvaneswari, Natesan; Kannan, Chellapandian

2011-05-15

91

Concept and demonstration of all organic Gratzel solar cell (dye sensitized solar cell)  

Microsoft Academic Search

The authors present the concept of ``all organic Gratzel\\/dye sensitized solar cell'' and demonstrate such a device using high Tauc band gap (above 2.5 eV) amorphous carbon thin films doped with nitrogen (n type) deposited by microwave assisted surface wave plasma chemical vapor deposition and sensitized with copper-phthalocyanine thin films. Open circuit voltage and short circuit current density obtained are

Prakash R. Somani; Savita P. Somani; M. Umeno; A. Sato

2006-01-01

92

A Robust Organic Dye for Dye Sensitized Solar Cells Based on Iodine/Iodide Electrolytes Combining High Efficiency and Outstanding Stability  

PubMed Central

Among the new photovoltaic technologies, the Dye-Sensitized Solar Cell (DSC) is becoming a realistic approach towards energy markets such as BIPV (Building Integrated PhotoVoltaics). In order to improve the performances of DSCs and to increase their commercial attractiveness, cheap, colourful, stable and highly efficient ruthenium-free dyes must be developed. Here we report the synthesis and complete characterization of a new purely organic sensitizer (RK1) that can be prepared and synthetically upscaled rapidly. Solar cells containing this orange dye show a power conversion efficiency of 10.2% under standard conditions (AM 1.5G, 1000?Wm?2) using iodine/iodide as the electrolyte redox shuttle in the electrolyte, which is among the few examples of DSC using an organic dyes and iodine/iodide red/ox pair to overcome the 10% efficiency barrier. We demonstrate that the combination of this dye with an ionic liquid electrolyte allows the fabrication of solar cells that show power conversion efficiencies of up to 7.36% that are highly stable with no measurable degradation of initial performances after 2200?h of light soaking at 65°C under standard irradiation conditions. RK1 achieves one of the best output power conversion efficiencies for a solar cell based on the iodine/iodide electrolyte, combining high efficiency and outstanding stability.

Joly, Damien; Pelleja, Laia; Narbey, Stephanie; Oswald, Frederic; Chiron, Julien; Clifford, John N.; Palomares, Emilio; Demadrille, Renaud

2014-01-01

93

HPLC and molecular spectroscopic investigations of the red dye obtained from an ancient Pazyryk textile  

Microsoft Academic Search

The cloth specimens of Pazyryk culture from frozen burials of Altai Mountains (500–200 B.C.) were investigated by molecular spectroscopy and high performance liquid chromatography coupled with diode-array and mass selective detection. The qualitative and quantitative analyses of ancient red dyes were conducted. Natural dyes of plant origin – alizarin and purpurin and of insect origin – carminic acid and kermesic

G. G. Balakina; V. G. Vasiliev; E. V. Karpova; V. I. Mamatyuk

2006-01-01

94

Solution-processed organic photovoltaics based on indoline dye molecules developed in dye-sensitized solar cells.  

PubMed

A donor-acceptor (D-A) type indoline dye, D149, was used as an electron donor in solution-processed organic solar cells (OSCs). For bulk-heterojunction (BHJ) type OSCs with PC70BM as electron acceptor, the power conversion efficiency (PCE) is sensitive to the amount of D149 in the D149/PC70BM blend film. When the concentration of D149 in the blend film was as low as 5%, the highest PCE of up to 1.29%, together with a short-circuit current density (Jsc) of 4.58 mA·cm-2, an open-circuit voltage (Voc) of 0.90 V and a fill factor (FF) of 0.31, was achieved. In order to improve the PCE of D149-based OSCs, a bilayer-heterojunction configuration with C70 as electron acceptor has been employed. By optimizing the thickness of the D149 layer and varying the electron- and hole-transport layers, a highest PCE of up to 2.28% with a Jsc of 4.38 mA·cm-2, a Voc of 0.77 V, and an FF of 0.62 was achieved under AM 1.5G solar illumination (100 mW·cm-2). PMID:23470338

Liu, Zhaoyang; Ojima, Haruhiko; Hong, Ziruo; Kido, Junji; Tian, Wenjing; Wang, Xiao-Feng

2013-01-01

95

Highly oriented surface-growth and covalent dye labeling of mesoporous metal-organic frameworks.  

PubMed

Mesoporous amino-functionalized metal-organic framework thin films with the UiO-68 topology were grown in a highly oriented fashion on two different self-assembled monolayers on gold. The oriented MOF films were covalently modified with the fluorescent dye Rhodamine B inside the pore system, as demonstrated with size-selective fluorescence quenching studies. Our study suggests that mesoporous metal-organic frameworks are promising hosts for the covalent attachment of numerous functional moieties in a molecularly designed crystalline environment. PMID:22367006

Hinterholzinger, Florian M; Wuttke, Stefan; Roy, Pascal; Preusse, Thomas; Schaate, Andreas; Behrens, Peter; Godt, Adelheid; Bein, Thomas

2012-04-14

96

Indigo carmine enhances phenylephrine-induced contractions in an isolated rat aorta  

PubMed Central

Background The intravenous administration of indigo carmine has been reported to produce transiently increased blood pressure in patients. The goal of this in vitro study was to examine the effect of indigo carmine on phenylephrine-induced contractions in an isolated rat aorta and to determine the associated cellular mechanism with particular focus on the endothelium-derived vasodilators. Methods The concentration-response curves for phenylephrine were generated in the presence or absence of indigo carmine. Phenylephrine concentration-response curves were generated for the endothelium-intact rings pretreated independently with a nitric oxide synthase inhibitor, N?-nitro-L-arginine methyl ester (L-NAME), a cyclooxygenase inhibitor, indomethacin, and a low-molecular-weight superoxide anion scavenger, tiron, in the presence or absence of indigo carmine. The fluorescence of oxidized dichlorofluorescein was measured in rat aortic vascular smooth muscle cells cultured in the control, indigo carmine alone and tiron plus indigo carmine. Results Indigo carmine (10-5 M) increased the phenylephrine-induced maximum contraction in the endothelium-intact rings with or without indomethacin, whereas indigo carmine produced a slight leftward shift in the phenylephrine concentration-response curves in the endothelium-denuded rings and L-NAME-pretreated endothelium-intact rings. In the endothelium-intact rings pretreated with tiron (10-2 M), indigo carmine did not alter phenylephrine concentration-response curves significantly. Indigo carmine (10-5 M) increased the fluorescence of oxidized dichlorofluorescein in the vascular smooth muscle cells, whereas tiron abolished the indigo carmine-induced increase in oxidized dichlorofluorescein fluorescence. Conclusions Indigo carmine increases the phenylephrine-induced contraction mainly through an endothelium-dependent mechanism involving the inactivation of nitric oxide caused by the increased production of reactive oxygen species.

Choi, Yun Suk; Ok, Seong-Ho; Lee, Seung Min; Park, Sang-Seung; Ha, Yu Mi; Chang, Ki Churl; Kim, Hye Jung; Shin, Il-Woo

2011-01-01

97

Concept and demonstration of all organic Gratzel solar cell (dye sensitized solar cell)  

NASA Astrophysics Data System (ADS)

The authors present the concept of ``all organic Gratzel/dye sensitized solar cell'' and demonstrate such a device using high Tauc band gap (above 2.5 eV) amorphous carbon thin films doped with nitrogen (n type) deposited by microwave assisted surface wave plasma chemical vapor deposition and sensitized with copper-phthalocyanine thin films. Open circuit voltage and short circuit current density obtained are about 0.53 V (versus Ag/AgCl, reference electrode) and 8.52×10-6 A/cm2, respectively. The mechanism of photovoltaic action in such cells may be similar to dye sensitized photoelectrochemical cells using nano-TiO2/ZnO porous thick films.

Somani, Prakash R.; Somani, Savita P.; Umeno, M.; Sato, A.

2006-08-01

98

LASERS AND LASER AMPLIFIERS: Synchronous pumping of jet organic dye lasers with sinusoidally modulated argon laser radiation  

NASA Astrophysics Data System (ADS)

A simple and convenient method of synchronous pumping of jet organic dye lasers is described. In this method a cw argon laser with sinusoidally modulated radiation is used as the pump source. The argon laser is modulated by a standing-wave acoustooptic modulator operating at the frequency of intermode beats of the dye laser. The results are given of an experimental investigation of the width of the mode locking range under synchronous pumping conditions and of the time and energy characteristics of the output radiation. The duration of the output pulses of the dye laser was ~ 350 ps under synchronous pumping conditions.

Ra?, G. I.; Ustinov, B. P.; Sharonov, G. V.

1988-09-01

99

Nanocrystalline electrodes based on nanoporous-walled WO3 nanotubes for organic-dye-sensitized solar cells.  

PubMed

Nanoporous-walled tungsten oxide (WO(3)) nanotubes (NTs), which had a more positive conduction band edge level compared to that of TiO(2), were applied to various organic dyes for dye-sensitized solar cells (DSSCs). The dye-sensitized WO(3) NTs displayed photosensitization for the organic dyes whose lowest unoccupied molecular orbital (LUMO) level was relatively positive to the conventional TiO(2) electrode and, thus, not applicable for electron injection to the TiO(2) electrode. Electron transport time and electron lifetime for the WO(3) electrode in the DSSCs were investigated. In comparison to the DSSCs based on TiO(2), SnO(2), and In(2)O(3), the WO(3) DSSCs displayed the longest lifetime. On the other hand, non-diffusion-like electron transport may be an issue to apply WO(3) for the DSSCs. PMID:21942210

Hara, Kohjiro; Zhao, Zhi-Gang; Cui, Yan; Miyauchi, Masahiro; Miyashita, Masanori; Mori, Shogo

2011-10-18

100

Efficient adsorbents of nanoporous aluminosilicate monoliths for organic dyes from aqueous solution.  

PubMed

Growing public awareness on the potential risk to humans of toxic chemicals in the environment has generated demand for new and improved methods for toxicity assessment and removal, rational means for health risk estimation. With the aim of controlling nanoscale adsorbents for functionality in molecular sieving of organic pollutants, we fabricated cubic Im3m mesocages with uniform entrance and large cavity pores of aluminosilicates as highly promising candidates for the colorimetric monitoring of organic dyes in an aqueous solution. However, a feasible control over engineering of three-dimensional (3D) mesopore cage structures with uniform entrance (~5 nm) and large cavity (~10 nm) allowed the development of nanoadsorbent membranes as a powerful tool for large-quantity and high-speed (in minutes) adsorption/removal of bulk molecules such as organic dyes. Incorporation of high aluminum contents (Si/Al=1) into 3D cubic Im3m cage mesoporous silica monoliths resulted in small, easy-to-use optical adsorbent strips. In such adsorption systems, natural surfaces of active acid sites of aluminosilicate strips strongly induced both physical adsorption of chemically responsive dyes and intraparticle diffusion into cubic Im3m mesocage monoliths. Results likewise indicated that although aluminosilicate strips with low Si/Al ratios exhibit distortion in pore ordering and decrease in surface area and pore volume, enhancement of both molecular converges and intraparticle diffusion onto the network surfaces and into the pore architectures of adsorbent membranes was achieved. Moreover, 3D mesopore cage adsorbents are reversible, offering potential for multiple adsorption assays. PMID:21514595

El-Safty, Sherif A; Shahat, Ahmed; Awual, Md Rabiul

2011-07-01

101

Effect of viscosity, basicity and organic content of composite flocculant on the decolorization performance and mechanism for reactive dyeing wastewater  

Microsoft Academic Search

A coagulation\\/flocculation process using the composite flocculant polyaluminum chloride-epichlorohydrin dimethylamine (PAC-EPI-DMA) was employed for the treatment of an anionic azo dye (Reactive Brilliant Red K-2BP dye). The effect of viscosity (?), basicity (B = [OH]\\/[Al]) and organic content (Wp) on the flocculation performance as well as the mechanism of PAC-EPI-DMA flocculant were investigated. The ? was the key factor affecting

Yuanfang Wang; Baoyu Gao; Qinyan Yue; Yan Wang

2011-01-01

102

Neutral color tuning of polymer electrochromic devices using an organic dye.  

PubMed

Herein, we present a facile, one-step method to color tune electrochromic devices (ECDs) that switch between two neutral colors via in situ electrochemical polymerization of electroactive monomers in the presence of a small molecule organic yellow dye using all commercially available materials. These devices exhibited photopic contrasts of ca. 30% without background correction when assembled on flexible PET-ITO substrates. In addition, devices exhibited switching speeds as low as 1 second, color uniformity, and stability. Large defect free ECDs of 100 cm(2) were fabricated exceeding the active switch area required for goggles, lenses, and small display applications. PMID:24927214

Zhu, Yumin; Otley, Michael T; Kumar, Amrita; Li, Mengfang; Zhang, Xiaozheng; Asemota, Chris; Sotzing, Gregory A

2014-07-01

103

Effect of viscosity, basicity and organic content of composite flocculant on the decolorization performance and mechanism for reactive dyeing wastewater.  

PubMed

A coagulation/flocculation process using the composite flocculant polyaluminum chloride-epichlorohydrin dimethylamine (PAC-EPI-DMA) was employed for the treatment of an anionic azo dye (Reactive Brilliant Red K-2BP dye). The effect of viscosity (eta), basicity (B = [OH]/[Al]) and organic content (W(P)) on the flocculation performance as well as the mechanism of PAC-EPI-DMA flocculant were investigated. The eta was the key factor affecting the dye removal efficiency of PAC-EPI-DMA. PAC-EPI-DMA with an intermediate eta (2400 mPa x sec) gave higher decolorization efficiency by adsorption bridging and charge neutralization due to the co-effect of PAC and EPI-DMA polymers. The W(P) of the composite flocculant was a minor important factor for the flocculation. The adsorption bridging of PAC-EPI-DMA with eta of 300 or 4300 mPa x sec played an important role with the increase of W(P), whereas the charge neutralization of them was weaker with the increase of W(P). There was interaction between W(P) and B on the removal of reactive dye. The composite flocculant with intermediate viscosity and organic content was effective for the treatment of reactive dyeing wastewater, which could achieve high reactive dye removal efficiency with low organic dosage. PMID:22432257

Wang, Yuanfang; Gao, Baoyu; Yue, Qinyan; Wang, Yan

2011-01-01

104

A Research Module for the Organic Chemistry Laboratory: Multistep Synthesis of a Fluorous Dye Molecule  

PubMed Central

A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world.

2014-01-01

105

Profound Hypotension after an Intradermal Injection of Indigo Carmine for Sentinel Node Mapping  

PubMed Central

Intradermal injections of indigo carmine for sentinel node mapping are considered safe and no report of an adverse reaction has been published. The authors described two cases of profound hypotension in women that underwent breast-conserving surgery after an intradermal injection of indigo carmine into the periareolar area for sentinel node mapping.

Jo, Youn Yi; Lee, Mi Geum; Yun, Soon Young

2013-01-01

106

Screening for larvicidal activity of ten carminative plants.  

PubMed

Ten species of plants, reported to possess carminative property, were screened for larvicidal potential against Culex quinquefasciatus by exposing early 4th instar larvae to a series of concentrations of the ethanolic extracts of the plants. Mortality counts were made after 24 hours exposure. Probit analysis using computerized Harvard Programming (Hg1, 2) was employed to determine the LC50, LC95 and LC99 values in order to compare the larvicidal potency of the ten plants. Marked larvicidal effects were seen with Kaempferia galanga, Illicium vernum and Spilanthes acmella having LC50 values of 50.54, 54.11 and 61.43 ppm, respectively. PMID:10437975

Pitasawat, B; Choochote, W; Kanjanapothi, D; Panthong, A; Jitpakdi, A; Chaithong, U

1998-09-01

107

Removal of Dissolved Organic Carbon and Color from Dyeing Wastewater by Pre-ozonation and Subsequent Biological Treatment  

Microsoft Academic Search

The effects of pre-ozonation and subsequent biological treatment on the decrease in dissolved organic carbon (DOC) and color from dyeing wastewater were investigated. Moreover, the compositions of organic compounds in raw wastewater (RW) and the respective treated waters were estimated, and microscopic observations of the mixed liquor were conducted. The amount of ozone required to remove 1 mg of DOC

Nobuyuki Takahashi; Tomoya Kumagai

2006-01-01

108

Hierarchical assembly of metal nanoparticles, quantum dots and organic dyes using DNA origami scaffolds  

NASA Astrophysics Data System (ADS)

The self-assembly of nanoscale elements into three-dimensional structures with precise shapes and sizes is important in fields such as nanophotonics, metamaterials and biotechnology. Short molecular linkers have previously been used to create assemblies of nanoparticles, but the approach is limited to small interparticle distances, typically less than 10 nm. Alternatively, DNA origami can precisely organize nanoscale objects over much larger length scales. Here we show that rigid DNA origami scaffolds can be used to assemble metal nanoparticles, quantum dots and organic dyes into hierarchical nanoclusters that have a planet-satellite-type structure. The nanoclusters have a tunable stoichiometry, defined distances of 5-200 nm between components, and controllable overall sizes of up to 500 nm. We also show that the nanoscale components can be positioned along the radial DNA spacers of the nanostructures, which allows short- and long-range interactions between nanoparticles and dyes to be studied in solution. The approach could, in the future, be used to construct efficient energy funnels, complex plasmonic architectures, and porous, nanoengineered scaffolds for catalysis.

Schreiber, Robert; Do, Jaekwon; Roller, Eva-Maria; Zhang, Tao; Schüller, Verena J.; Nickels, Philipp C.; Feldmann, Jochen; Liedl, Tim

2014-01-01

109

Super-resolution recordable disc with organic dye for recording layer  

NASA Astrophysics Data System (ADS)

A new structure of super resolution optical disk with organic dye for recording layer was proposed. By utilizing of Sb thin film for the mask layer, below-diffraction-limited marks on organic recording layer could be recorded and retrieved. The mark size as small as 120nm could be read out on the current dynamic tester of digital versatile recordable disc (DVD-R). The conditions of optical pickup head are 635nm of laser wavelength (l) and 0.6 of lens numerical aperture (NA). The carrier-to-noise ratio (CNR) from recorded marks of 200nm was more than 28.5dB at low readout power of 2mW and at a constant linear velocity (CLV) equals 3.5 m/s. The recording layer with modified composition owned high thermal stability and the readout durability was more than 6 X 104 cycles without any decreasing of CNR.

Hsu, Wei-Chih; Tsai, Song Yeu; Kuo, P. C.; Tseng, Mei-Rurng; Hsu, Shih-Peng; Hung, Tien-Tsan; Chang, Chih-Li

2002-01-01

110

Near infrared organic semiconducting materials for bulk heterojunction and dye-sensitized solar cells.  

PubMed

Dye sensitized solar cells (DSSCs) and bulk heterojunction (BHJ) solar cells have been the subject of intensive academic interest over the past two decades, and significant commercial effort has been directed towards this area with the vison of developing the next generation of low cost solar cells. Materials development has played a vital role in the dramatic improvement of both DSSC and BHJ solar cell performance in the recent years. Organic conjugated polymers and small molecules that absorb solar light in the visible and near infrared (NIR) regions represent a class of emering materials and show a great potential for the use of different optoelectronic devices such as DSSCs and BHJ solar cells. This account describes the emering class of near infrared (NIR) organic polymers and small molecules having donor and acceptors units, and explores their potential applications in the DSSCs and BHJ solar cells. PMID:24890453

Singh, Surya Prakash; Sharma, G D

2014-06-01

111

Nanoscale insight into the exfoliation mechanism of graphene with organic dyes: effect of charge, dipole and molecular structure  

NASA Astrophysics Data System (ADS)

We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets. A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups. By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene-dye interaction energy, the molecular structure and the amount of graphene flakes solubilized. The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a ``sliding'' mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene. While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole.We study the mechanism of surface adsorption of organic dyes on graphene, and successive exfoliation in water of these dye-functionalized graphene sheets. A systematic, comparative study is performed on pyrenes functionalized with an increasing number of sulfonic groups. By combining experimental and modeling investigations, we find an unambiguous correlation between the graphene-dye interaction energy, the molecular structure and the amount of graphene flakes solubilized. The results obtained indicate that the molecular dipole is not important per se, but because it facilitates adsorption on graphene by a ``sliding'' mechanism of the molecule into the solvent layer, facilitating the lateral displacement of the water molecules collocated between the aromatic cores of the dye and graphene. While a large dipole and molecular asymmetry promote the adsorption of the molecule on graphene, the stability and pH response of the suspensions obtained depend on colloidal stabilization, with no significant influence of molecular charging and dipole. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00258f

SchlierfThese Authors Contributed Equally To This Work., Andrea; Yang, Huafeng; Gebremedhn, Elias; Treossi, Emanuele; Ortolani, Luca; Chen, Liping; Minoia, Andrea; Morandi, Vittorio; Samorì, Paolo; Casiraghi, Cinzia; Beljonne, David; Palermo, Vincenzo

2013-05-01

112

Spectrophotometric determination of trace water in organic solvents with a near infrared absorbing dye.  

PubMed

A spectrophotometric method for the determination of trace water in organic solvents using a near infrared absorbing dye has been developed. This method is based on the effect that a minor change in polarity of the solvent caused by trace water content determines the extent of aggregation of a near-infrared dye monomer. This change can be detected spectrophotometrically. The calibration curves for methanol, ethanol, and isopropanol were determined. This method has the highest sensitivity (em = 16.73 unit) for water in isopropanol and the lowest sensitivity (em = 2.806 unit) for water in methanol. The correlation coefficient (R)(2) values for the regression lines ranges from 0.990-0.998. The linear range of the method for ethanol is 0.001-0.5%, for isopropanol is 0.001-0.1%, and for methanol is 0.001-1.0%. The limit of detection for ethanol, isopropanol, and methanol are 0.0001, 0.0001, and 0.005% water, respectively. The developed method is sensitive, simple and easy to operate, and the cost of analysis is low. PMID:18966939

Li, M; Pacey, G E

1997-11-01

113

Quantitative determination of carmine in foods by high-performance liquid chromatography.  

PubMed

A simple and rapid method has been developed and validated for the determination of carmine in foods. Samples were homogenised and extracted with 0.05M NaOH, followed by centrifugation. The resulting solution was filtered and injected to HPLC. Carmine was separated by HPLC using an NovaPak C18 column coupled to a photodiode array detector. The contents of carmine were finally quantified using corresponding calibration curves over ranges of 1.0-100?gml(-1), with good correlation coefficients (r(2)=0.9999). The recoveries of carmine from foods spiked at levels of 10, 50, and 100?gg(-1) which ranged from 90.4% to 96.2% with relative standard deviations between 2.8% and 6.8%. Limit of detection and limit of quantification of carmine were 0.4 and 1.0?gml(-1), respectively. This method was found to be useful to distinguish carmine from carminic acid, a major component of cochineal extract. The method has been successfully applied to various foods. PMID:24731378

Lim, Ho-Soo; Choi, Jae-Chon; Song, Sung-Bong; Kim, Meehye

2014-09-01

114

Molecular engineering and theoretical investigation of organic sensitizers based on indoline dyes for quasi-solid state dye-sensitized solar cells.  

PubMed

Novel indoline dyes, I-1-I-4, with structural modification of ?-linker group in the D-?-A system have been synthesized and fully characterized. Molecular engineering through expanding the ?-linker segment has been performed. The ground and excited state properties of the dyes have been studied by means of density functional theory (DFT) and time-dependent DFT (TD-DFT). Larger ?-conjugation linkers would lead to broader spectral response and higher molar extinction coefficient but would decrease dye-loaded amount on TiO(2) electrode and LUMO level. While applied in DSSCs, the variation trends in short-circuit current density (J(sc)) and open-circuit voltage (V(oc)) were observed to be opposite to each other. The internal reasons were studied by experimental data and theoretical calculations in detail. Notably, I-2 showed comparable photocurrent values with liquid and quasi-solid state electrolyte, which suggested through molecular engineering of organic sensitizers the dilemma between optical absorption and charge diffusion lengths can be balanced well. Through studies of photophysical, electrochemical, and theoretical calculation results, the internal relations between chemical structure and efficiency have been revealed, which serve to enhance our knowledge regarding design and optimization of new sensitizers for quasi-solid state DSSCs, providing a powerful strategy for prediction of photovoltaic performances. PMID:21455531

Liu, Bo; Wu, Wenjun; Li, Xiaoyan; Li, Lei; Guo, Shaofu; Wei, Xiaoru; Zhu, Weihong; Liu, Qingbin

2011-05-21

115

Dendritic CdS assemblies for removal of organic dye molecules.  

PubMed

In this paper, novel CdS 3D assemblies are prepared via a facile and effective hydrothermal route using dimethyl sulfoxide as the growth template. Morphologies, microstructures and photocatalytic properties of the as-synthesized products are investigated in detail. It was found that dimethyl sulfoxide played an important role in the formation of CdS assemblies. A possible growth mechanism for CdS assemblies was proposed based on the experimental results. In addition, CdS assemblies exhibit superior photocatalytic activities by the photodegradation of eosin B, Methyl orange (MO) and Rhodamine B (RhB) under visible light irradiation, with a comparison with other CdS nanostructures, P25 and ?-Fe2O3 powders, demonstrating potential applications in removal of organic dye molecules from waste water. PMID:24481318

Yu, Zhou; Qu, Fengyu; Wu, Xiang

2014-03-28

116

Optical Stark effect in organic dyes probed with optical pulses of 6-fs duration  

NASA Astrophysics Data System (ADS)

We report the first observation of the dynamic optical Stark shift on a femtosecond time scale. Pump pulses of 50-fs duration with peak intensities of 1011-1012 W/cm2 were used to cause a Stark shift of the S0 to S1 transition in the organic-dye molecule rhodamine-B. The perturbed spectra were observed with the use of probe pulses of 6-fs duration. The inferred effective transition dipole moment of 7 D is in good agreement with the value derived from the absorption line strength. At the higher pump powers, line-shape distortions and a reduction in the apparent line strength are also noted and discussed.

Becker, P. C.; Fork, R. L.; Brito Cruz, C. H.; Gordon, J. P.; Shank, C. V.

1988-06-01

117

Confinement of pyridinium hemicyanine dye within an anionic metal-organic framework for two-photon-pumped lasing  

NASA Astrophysics Data System (ADS)

Two-photon-pumped dye lasers are very important because of their applications in wavelength up-conversion, optical data storage, biological imaging and photodynamic therapy. Such lasers are very difficult to realize in the solid state because of the aggregation-caused quenching. Here we demonstrate a new two-photon-pumped micro-laser by encapsulating the cationic pyridinium hemicyanine dye into an anionic metal-organic framework (MOF). The resultant MOF?dye composite exhibits significant two-photon fluorescence because of the large absorption cross-section and the encapsulation-enhanced luminescent efficiency of the dye. Furthermore, the well-faceted MOF crystal serves as a natural Fabry-Perot resonance cavity, leading to lasing around 640?nm when pumped with a 1064-nm pulse laser. This strategy not only combines the crystalline benefit of MOFs and luminescent behaviour of organic dyes but also creates a new synergistic two-photon-pumped lasing functionality, opening a new avenue for the future creation of solid-state photonic materials and devices.

Yu, Jiancan; Cui, Yuanjing; Xu, Hui; Yang, Yu; Wang, Zhiyu; Chen, Banglin; Qian, Guodong

2013-10-01

118

Confinement of pyridinium hemicyanine dye within an anionic metal-organic framework for two-photon-pumped lasing.  

PubMed

Two-photon-pumped dye lasers are very important because of their applications in wavelength up-conversion, optical data storage, biological imaging and photodynamic therapy. Such lasers are very difficult to realize in the solid state because of the aggregation-caused quenching. Here we demonstrate a new two-photon-pumped micro-laser by encapsulating the cationic pyridinium hemicyanine dye into an anionic metal-organic framework (MOF). The resultant MOF [symbol: see text] dye composite exhibits significant two-photon fluorescence because of the large absorption cross-section and the encapsulation-enhanced luminescent efficiency of the dye. Furthermore, the well-faceted MOF crystal serves as a natural Fabry-Perot resonance cavity, leading to lasing around 640 nm when pumped with a 1064-nm pulse laser. This strategy not only combines the crystalline benefit of MOFs and luminescent behaviour of organic dyes but also creates a new synergistic two-photon-pumped lasing functionality, opening a new avenue for the future creation of solid-state photonic materials and devices. PMID:24173352

Yu, Jiancan; Cui, Yuanjing; Xu, Hui; Yang, Yu; Wang, Zhiyu; Chen, Banglin; Qian, Guodong

2013-01-01

119

VIS absorption spectrophotometry of disperse dyes  

Microsoft Academic Search

In the investigations of the dyeing processes, the low solubility of disperse dyes in water represents a practical problem for the determination of dye concentration in dyebaths and waste waters. Therefore the use of an organic solvent which, dissolves disperse dyes, is recommended in visible spectrophotometry of disperse dyes. Three organic solvents (ethanol, N,N-dimethylformamide, acetone) and two disperse dyes, the

Vera Golob; Lidija Tušek

1999-01-01

120

Simple metal-free organic D-pi-A dyes with alkoxy- or fluorine substitutions: application in dye sensitized solar cells.  

PubMed

Two new metal-free organic sensitizers with simplest structural variations have been synthesized for application in nanocrystalline TiO2 sensitized solar cells. The donor-pi-bridge-acceptor (D-pi-A) structure dyes, Y2 and Y3 each designed with three parts, an electron donor unit (substituted phenyl), a linker unit (thiophene), and an anchor unit (cyanoacrylic acid) showed maximal monochromatic incident photon to current conversion efficiencies (IPCE) in a device reaching upto 67% and 82% respectively. The organic sensitizers with 3,4,5-trimethoxy phenyl (Y3) as donor moieties obtained better solar light to electrical energy conversion efficiencies of 3.30% where as the organic sensitizer with 2,4-difluoro phenyl as donor (Y2) showed comparatively lower efficiency of 1.02%. The efficiency obtained with the reference sensitizer N719 under similar fabrication and evaluation conditions was 5.84%. PMID:22905490

Chandrasekharam, M; Chiranjeevi, B; Gupta, K S V; Singh, Surya Prakash; Islam, A; Han, L; Kantam, M Lakshmi

2012-06-01

121

Template-free hydrothermal derived cobalt oxide nanopowders: Synthesis, characterization, and removal of organic dyes  

SciTech Connect

Graphical abstract: XRD patterns of the products obtained by hydrothermal treatment at 160 °C for 24 h, and at different [Co{sup 2+}]/[CO{sub 3}{sup 2?}] ratios: (a) 1:6, (b) 1:3, (c) 1:1.5, (d) 1:1, (e) 1:0.5. Highlights: ? Spinel cobalt oxide nanoparticles with different morphologies were prepared by hydrothermal approach. ? The optical characteristics of the as-prepared cobalt oxide revealed the presence of two band gaps. ? Adsorption of methylene blue dye on Co{sub 3}O{sub 4} was investigated and the percent uptake was found to be >99% in 24 h. -- Abstract: Pure spinel cobalt oxide nanoparticles were prepared through hydrothermal approach using different counter ions. First, the pure and uniform cobalt carbonate (with particle size of 21.8–29.8 nm) were prepared in high yield (94%) in an autoclave in absence unfriendly organic surfactants or solvents by adjusting different experimental parameters such as: pH, reaction time, temperature, counter ions, and (Co{sup 2+}:CO{sub 3}{sup 2?}) molar ratios. Thence, the spinel Co{sub 3}O{sub 4} (with mean particle size of 30.5–47.35 nm) was produced by thermal decomposition of cobalt carbonate in air at 500 °C for 3 h. The products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), transmission electron microscope (TEM), scanning electron microscope (SEM), and thermal analysis (TA). Also, the optical characteristics of the as-prepared Co{sub 3}O{sub 4} nanoparticles revealed the presence of two band gaps (1.45–1.47, and 1.83–1.93 eV). Additionally, adsorption of methylene blue dye on Co{sub 3}O{sub 4} nanoparticles was investigated and the uptake% was found to be >99% in 24 h.

Nassar, Mostafa Y. [Chemistry Department, Faculty of Science, Benha University, Benha 13518 (Egypt)] [Chemistry Department, Faculty of Science, Benha University, Benha 13518 (Egypt); Ahmed, Ibrahim S., E-mail: isahmed2010@gmail.com [Chemistry Department, Faculty of Science, Benha University, Benha 13518 (Egypt)

2012-09-15

122

Photoinduced absorption measurement on a microchip equipped with organic dye-doped polymer waveguide  

NASA Astrophysics Data System (ADS)

We have fabricated a waveguide-type optical sensing microchip and succeeded in on-chip photoinduced absorption (PIA) spectroscopy. The PIA microchip was fabricated with a conventional photolithographic technique and consisted of plastic optical waveguides and microfluidic channels. Furthermore, a serially-cascaded polymer waveguide doped with organic dyes was integrated on this microchip, which was fabricated using a self-written waveguide process. This dye-doped waveguide was pumped by a UV light emitting diode (UV-LED) and used as a probe light source with a broad emission spectrum. At the same time, a solution of test material in the microfluidic channel was synchronously pumped by a UV-LED or UV laser diode. Since the transmission spectrum of the photo-excited test material could be measured, the PIA spectra were obtained easily. In this study, we have demonstrated the on-chip PIA measurements for two classes of test materials, rare-earth complex and chlorophyll molecules. In the measurement for the aqueous solution of Neodymium (III) acetate hydrate, PIA signals attributed to the 4f-4f transition was observed. Furthermore, by varying the modulation frequency of the pulsed optical pumping, lifetime analysis of the excited 4f states was achieved. In the measurements for the ethanol solutions of chlorophyll a and chlorophyll b, PIA signals were observed at the wavelength near the Q-band absorption peaks. These spectra were very similar to the well-known feature for the photosystem II protein complex observed in a conventional PIA system. From these results, it is expected that the onchip PIA measurement technique is applicable to the transient analyses for the material systems with photoexcited charge transfer.

Kawaguchi, T.; Nagai, K.; Yamashita, K.

2013-05-01

123

Theoretical analysis of the absorption spectra of organic dyes differing by the conjugation sequence: illusion of negative solvatochromism  

NASA Astrophysics Data System (ADS)

Absorption peak maxima of two organic dyes differing by the position of the methine unit differ by 61 nm in dioxane and 128 nm in acetonnitrile. The difference is not reproduced by TDDFT using ab initio or hybrid functionals. TDDFT errors are different between the molecules due to a different albeit small extent of charge transfer, leading to a qualitative failure of TDDFT to predict relative energetics of the dyes. The TDDFT errors in non-polar solvents (such as dioxane) could be corrected based on the approach of Peach et al. (J. Chem. Phy. 128, 044118 (2008)). Here, we focus on the effect on the absorption spectrum of a polar solvent, specifically of the different between the two molecules sign of the solvatochromic shift vs. dioxane. Using the corrrection due to Peach et al, the absolute TDDFT errors can be brought within accetable ranges of 0.2-0.3 eV with the PCM solvent model, and the blue shift vs.dioxane is reporoduced, although both dyes are predicted to exhibit positive solvatochromism. The inclusion of explicit solvent molecules forming hydrogen bonds with the dye did not appreciably change neither TDDFT energies nor the correction term. These results show the importance of a more careful assessment of computational errors in the strategy of computationaly dye design by changing the conjugation order, where they are expected to be more important than in the case of an extension of the size of conjugation, and more so when polar solvents are used.

Manzhos, Sergei; Segawa, Hiroshi; Yamashita, Koichi

2012-05-01

124

Organic heterojunctions of layered perylene and phthalocyanine dyes: characterization with UV-photoelectron spectroscopy and luminescence quenching  

NASA Astrophysics Data System (ADS)

We present here the characterization of organic/organic' heterojunctions created from either of two perylene dyes, perylenetetracarboxylicdianhydride (PTCDA) or the bisimide derivative perylenetetracarboxylicdianhydride-N,N'-bis (butyl)imide (C4-PTCDI), and two chloro-metallated donor phthalocyanines (ClAlPc or ClInPc). The perylene dyes were selected to create thin films with the core of the perylene dye parallel to the substrate plane (PTCDA) or nearly vertical to the substrate plane, with layer planes defined by the butyl substituents (C4-PTCDI). We compare the frontier orbital offsets revealed by UV-photoelectron spectroscopy, and quenching of luminescence of the perylene dyes, as a function of Pc coverage. The ionization potentials (IPs) of the Pc layers, the degree to which interface dipoles are formed at the Pc/perylene dye interface, and the degree of quenching of the perylene luminescence are affected by the structure of the Pc/perylene interface. Pc/PTCDA heterojunctions show significant interface dipoles and higher IPs for the first-deposited Pc layers compared to Pc/C4-PTCDI heterojunctions, which show negligible interface dipoles and lower overall IP values for initial Pc layers. Luminescence of the selectively excited perylene layers is quenched by the addition of even submonolayer coverages of Pc. This quenching process occurs as a result of both energy transfer (perylene to Pc) and charge transfer (Pc to perylene). Luminescence from monomeric and aggregated ClAlPc and ClInPc monolayers is seen on C4-PTCDI films, whereas only luminescence from the aggregated forms of these Pcs is seen on PTCDA films. These studies reveal aspects of organic heterojunction energetics which may have important implications for organic solar cell design.

Alloway, Dana M.; Armstrong, Neal R.

2009-04-01

125

Removal of organic compounds during treating printing and dyeing wastewater of different process units.  

PubMed

Wastewater in Shaoxing wastewater treatment plant (SWWTP) is composed of more than 90% dyeing and printing wastewater with high pH and sulfate. Through a combination process of anaerobic acidogenic [hydraulic retention time (HRT) of 15h], aerobic (HRT of 20h) and flocculation-precipitation, the total COD removal efficiency was up to 91%. But COD removal efficiency in anaerobic acidogenic unit was only 4%. As a comparison, the COD removal efficiency was up to 35% in the pilot-scale upflow anaerobic sludge bed (UASB) reactor (HRT of 15h). GC-MS analysis showed that the response abundance of these wastewater samples decreased with their removal of COD. A main component of the raw influent was long-chain n-alkanes. The final effluent of SWWTP had only four types of alkanes. After anaerobic unit at SWWTP, the mass percentage of total alkanes to total organic compounds was slightly decreased while its categories increased. But in the UASB, alkanes categories could be removed by 75%. Caffeine as a chemical marker could be detected only in the effluent of the aerobic process. Quantitative analysis was given. These results demonstrated that GC-MS analysis could provide an insight to the measurement of organic compounds removal. PMID:17997469

Wang, J; Long, M C; Zhang, Z J; Chi, L N; Qiao, X L; Zhu, H X; Zhang, Z F

2008-03-01

126

Abatements of reduced sulphur compounds, colour, and organic matter from indigo dyeing effluents by electrocoagulation.  

PubMed

In the present study, the treatability of indigo dyeing effluents by the electrocoagulation (EC) process using stainless steel electrodes was experimentally investigated. The samples used were concentrated with main pollutant parameters of chemical oxygen demand (COD) (1000-1100 mg/L), reduced sulphur species (over 2000 mg SO2-(3)/L), and colour (0.12-0.13 1/cm). The study focused on the effect of main operation parameters on the EC process performance in terms of abatement of reduced sulphur compounds as well as decolourization and organic matter reduction. Results indicated that the performance of EC proved to be high providing total oxidation of the reduced sulphur compounds, almost complete decolourization, and COD removal up to 90%. Increasing applied current density from 22.5 to 45 mA/cm2 appreciably improved abatement of the reduced sulphur compounds for Sample I, but a further increase in the applied current density to 67.5 mA/cm2 did not accelerate the conversion rate to sulphate. The process performance was adversely affected by increasing initial concentration of the reduced sulphur compounds. Decolourization and organic matter removal efficiency enhanced with increasing applied current density. The main removal mechanism of the reduced sulphur compounds by EC was explained as conversion to sulphate via oxidation. Conversion rate to sulphate fitted pseudo-first-order kinetics very well. PMID:24956747

Tünay, Olcay; Sim?eker, Merve; Kabda?li, Isik; Olmez-Hanci, Tugba

2014-08-01

127

Removal of organic dyes using Cr-containing activated carbon prepared from leather waste.  

PubMed

In this work, hydrogen peroxide decomposition and oxidation of organics in aqueous medium were studied in the presence of activated carbon prepared from wet blue leather waste. The wet blue leather waste, after controlled pyrolysis under CO(2) flow, was transformed into chromium-containing activated carbons. The carbon with Cr showed high microporous surface area (up to 889 m(2)g(-1)). Moreover, the obtained carbon was impregnated with nanoparticles of chromium oxide from the wet blue leather. The chromium oxide was nanodispersed on the activated carbon, and the particle size increased with the activation time. It is proposed that these chromium species on the carbon can activate H(2)O(2) to generate HO radicals, which can lead to two competitive reactions, i.e. the hydrogen peroxide decomposition or the oxidation of organics in water. In fact, in this work we observed that activated carbon obtained from leather waste presented high removal of methylene blue dye combining the adsorption and oxidation processes. PMID:21752544

Oliveira, Luiz C A; Coura, Camila Van Zanten; Guimarães, Iara R; Gonçalves, Maraisa

2011-09-15

128

Photocatalytic degradation of organic dyes with manganese-doped ZnO nanoparticles.  

PubMed

Manganese-doped and undoped ZnO photocatalysts were synthesized via wet-chemical techniques. Doping of ZnO with manganese (Mn(2+)) was intended to create tail states within the band gap of ZnO. These can subsequently be used as efficient photocatalysts which can effectively degrade organic contaminants only with visible light irradiation. Photocatalysts prepared with these techniques, which were characterized with transmission electron microscopy (TEM), infrared spectroscopy (FTIR), photo-co-relation spectroscopy (PCS) and UV-vis-spectroscopy showed significant difference in the optical absorption of Mn-doped ZnO. Enhancement in optical absorption of Mn-doped ZnO indicates that it can be used as an efficient photocatalyst under visible light irradiation. The photo-reduction activities of photocatalysts were evaluated using a basic aniline dye, methylene blue (MB) as organic contaminant irradiated only with visible light from tungsten bulb. It was found that manganese-doped ZnO (ZnO:Mn(2+)) bleaches MB much faster than undoped ZnO upon its exposure to the visible light. The experiment demonstrated that the photo-degradation efficiency of ZnO:Mn(2+) was significantly higher than that of undoped ZnO and might also be better than the conventional metal oxide semiconductor such as TiO(2) using MB as a contaminant. PMID:18221834

Ullah, Ruh; Dutta, Joydeep

2008-08-15

129

Control of the spectral characteristics of organic dye molecules adsorbed in porous glass by preliminary chemical modification of the pore surface  

Microsoft Academic Search

The electron spectra of organic dye molecules adsorbed in silicate porous glass were modified by preliminary chemical hydrophobization\\u000a of the pore surface. A comparative study was made of the absorption spectra of various laser dyes introduced in modified and\\u000a initial unmodified porous glasses.

V. N. Beger; A. Yu. Fadeev; G. V. Lisichkin

1999-01-01

130

Quasi-solid-state dye-sensitized solar cells based on a sol–gel organic–inorganic composite electrolyte containing an organic iodide salt  

Microsoft Academic Search

An organic–inorganic composite gel electrolyte based on TiO2 gel, ?-butyrolactone (?-BL) and N-methyl pyridine iodide was prepared by the sol–gel method. This gel electrolyte shows high ambient ionic conductivity of 7.63mScm?1, which is close to the data of liquid electrolyte with the same organic iodide salt and ?-butyrolactone. Based on the gel electrolyte, a quasi-solid-state dye-sensitized solar cell was fabricated

Zhang Lan; Jihuai Wu; Dongbo Wang; Sancun Hao; Jianming Lin; Yunfang Huang

2007-01-01

131

Phenothiazine-sensitized organic solar cells: effect of dye anchor group positioning on the cell performance.  

PubMed

Effect of positioning of the cyanoacrylic acid anchoring group on ring periphery of phenothiazine dye on the performance of dye-sensitized solar cells (DSSCs) is reported. Two types of dyes, one having substitution on the C-3 aromatic ring (Type 1) and another through the N-terminal (Type 2), have been synthesized for this purpose. Absorption and fluorescence studies have been performed to visualize the effect of substitution pattern on the spectral coverage and electrochemical studies to monitor the tuning of redox levels. B3LYP/6-31G* studies are performed to visualize the frontier orbital location and their significance in charge injection when surface modified on semiconducting TiO?. New DSSCs have been built on nanocrystalline TiO? according to traditional two-electrode Grätzel solar cell setup with a reference cell based on N719 dye for comparison. The lifetime of the adsorbed phenothiazine dye is found to be quenched significantly upon immobilizing on TiO? suggesting charge injection from excited dye to semiconducting TiO?. The performances of the cells are found to be prominent for solar cells made out of Type 1 dyes compared to Type 2 dyes. This trend has been rationalized on the basis of spectral, electrochemical, computational, and electrochemical impedance spectroscopy results. PMID:23043502

Hart, Aaron S; K C, Chandra Bikram; Subbaiyan, Navaneetha K; Karr, Paul A; D'Souza, Francis

2012-11-01

132

An achievement of over 12 percent efficiency in an organic dye-sensitized solar cell.  

PubMed

Dye-sensitized solar cells fabricated by using a novel metal-free alkoxysilyl carbazole as a sensitizing dye and a Co(3+/2+)-complex redox electrolyte exhibited light-to-electric energy conversion efficiencies of over 12% with open-circuit photovoltages higher than 1 V by applying a hierarchical multi-capping treatment to the photoanode. PMID:24801395

Kakiage, Kenji; Aoyama, Yohei; Yano, Toru; Otsuka, Takahiro; Kyomen, Toru; Unno, Masafumi; Hanaya, Minoru

2014-06-18

133

Organic Dye Effects on DNAPL Entry Pressure in Water Saturated Porous Media  

Microsoft Academic Search

One of three diazo dyes with the same fundamental structure have been used in most studies of DNAPL behavior in porous media to stain the NAPL: Sudan III, Sudan IV, or Oil-Red-O. The dyes are generally implicitly assumed to not influence DNAPL behavior. That assumption was tested using simple entry pressure experiments.

2001-01-01

134

Photocatalytic destruction of organic dyes in aqueous TiO sub 2 suspensions using concentrated simulated and natural solar energy  

SciTech Connect

The photocatalytic destruction of several classes of organic dyes utilizing highly concentrated solar energy is reported. Several commercial samples of anatase TiO{sub 2} varying in particle size and purity were studied to determine catalytic activity with Degussa P25 grade being the most active. When immobilized on glass beads it remained highly active. The rate and extent of decomposition of the organic compounds were determined by UV/Vis spectroscopy and High Performance Liquid Chromatography (HPLC). Complete mineralization was confirmed by total organic carbon analysis as well as quantitative measurements of CO{sub 2} and various inorganic ions. In general, sulfur in the organic compounds is converted to sulfate ions and nitrogen is converted to ammonium and/or nitrate ions. The effect of increasing the flux of the radiation on the rate of decomposition of the dye was also studied. There is a dramatic rate increase as the flux is increase from 15 suns' (solar simulator) to 150 suns' (solar dish concentrator) with the increase being slightly greater than the square root of the increase in flux. This work suggests that potential exists for the use of highly concentrated sunlight in the removal of the textile dyes and biological stains from wastewater.

Reeves, P.; Ohlhausen, R.; Sloan, D.; Pamplin, K.; Scoggins, T.; Clark, C. (Abilene Christian Univ., TX (United States)); Hutchinson, B.; Green, D. (Pepperdine Univ., Malibu, CA (United States))

1992-01-01

135

High-performance plastic dye-sensitized solar cells based on low-cost commercial P25 TiO2 and organic dye.  

PubMed

High-performance plastic dye-sensitized solar cells (DSCs) based on low-cost commercial Degussa P25 TiO(2) and organic indoline dye D149 have been fabricated using electrophoretic deposition (EPD) with compression post-treatment at room temperature. The pressed EPD electrode outperformed the sintered EPD electrode and as-prepared EPD electrode in short-circuit current density and power conversion efficiency. About 150% and 180% enhancement in power conversion efficiency have been achieved in DSC devices with sintering and compression post-treatment as compared to the as-prepared electrode, respectively. Several characterizations including intensity modulated photocurrent spectroscopy, incident photon-to-electron conversion efficiency and electrochemical impedance spectra have been employed to reveal the nature of improvement with post-treatment. Experimental results indicate that the sintering and compression post-treatment are beneficial to improve the electron transport and thus lead to the enhancement of photocurrent and power conversion efficiency. In addition, the compression post-treatment is more efficient than sintering post-treatment in improving interparticle connection in the as-prepared EPD electrode. Under optimized conditions, the conversion efficiency of plastic devices with D149-sensitized P25 TiO(2) photoanode has reached 5.76% under illumination of AM 1.5G (100 mW cm(-2)). This study demonstrates that the EPD combined with compression post-treatment provides a way to fabricate highly efficient plastic photovoltaic devices. PMID:22324725

Yin, Xiong; Xue, Zhaosheng; Wang, Long; Cheng, Yueming; Liu, Bin

2012-03-01

136

High-voltage (1.8 V) tandem solar cell system using a GaAs\\/Al X Ga (1? X )As graded solar cell and dye-sensitised solar cells with organic dyes having different absorption spectra  

Microsoft Academic Search

Stacked multijunction (tandem) solar cells have been prepared by mechanically stacking dye-sensitised solar cells (DSCs) and a GaAs\\/AlXGa(1?X)As graded solar cell (GGC) as the top and bottom cells, respectively. Three organic dyes with different absorption spectra (D131, D102 and D205) were used in the DSCs, in order to match the photocurrent density between the DSC and the GGC. Tuning the

S. Ito; I. M. Dharmadasa; G. J. Tolan; J. S. Roberts; G. Hill; H. Miura; J.-H. Yum; P. Pechy; P. Liska; P. Comte; M. Grätzel

2011-01-01

137

Dye-doped silica nanoparticles as luminescent organized systems for nanomedicine.  

PubMed

The ability to find synergic solutions is the core of scientific research and scientific advancement. This is particularly true for medicine, where multimodal imaging and theranostic tools represent the frontier research. Nanotechnology, which by its very nature is multidisciplinary, has opened up the way to the engineering of new organized materials endowed with improved performances. In particular, merging nanoparticles and luminescent signalling can lead to the creation of unique tools for the design of inexpensive, hand-held diagnostic and theranostic kits. In this wide scenario, dye-doped silica nanoparticles constitute very effective nanoplatforms to obtain efficient luminescent, stable, biocompatible and targeted agents for biomedical applications. In this review we discuss the state of the art in the field of luminescent silica-based nanoparticles for medical imaging, starting with an overview of the most common synthetic approaches to these materials. Trying to rationalize the presentation of this extremely multifaceted and complex subject, we have gathered significant examples of systems applied in cancer research, also discussing those that take a multifunctional approach, including theranostic structures. Nanoprobes designed for applications that do not include cancer are a minor part, but interesting achievements have been published and we present a selection of these in the subsequent section. To conclude, we propose a debate on the advantages of creating chemosensors based on luminescent silica nanoparticles. This is far from easy but is a particularly valuable goal in the medical field and therefore subject to extensive research worldwide. PMID:24643354

Montalti, M; Prodi, L; Rampazzo, E; Zaccheroni, N

2014-05-27

138

Bright red organic light-emitting diodes doped with a fluorescent dye  

NASA Astrophysics Data System (ADS)

We have evaluated a synthetic red fluorescent dye, 6-methyl-3-[3-(1,1,6,6-tetramethyl-10-oxo2,3,5,6-tetrahydro-1H,4H,10H-11 -oxa-3a-aza-benzo[de]anthracen-9-yl)-acryloyl]-pyran-2,4-dione (AAAP), as a dopant for an organic light-emitting diode (LED). Bright emission of a good red (maximum luminance: 5600 cd/m2, chromaticity coordinates: x=0.63, y=0.36) was obtained. The device consisted of ITO/TPD(50 nm)/Alq3 doped with AAAP(1.5 mol %,15 nm)/bOXDF(20 nm)/Alq3(25 nm)/Mg:Ag (ITO: indium tin oxide, TPD: N, N'-diphenyl- N,N'-di(3-methylphenyl)-1, 1'biphenyl-4,4'-diamine, Alq3: tris (8-hydroxyquinolinato)-aluminum (III), bOXDF:2,2-bis[5-(4-biphenyl)-1,3,4-oxadiazole-2-yl-4,1 -phenylene]-hexafluoropropane). The bands of fluorescence of the Alq3 host and of absorption of the AAAP dopant overlap in an advantageous way, and insertion of the bOXDF layer between the emission layer, doped with AAAP, and Alq3 layer, made for a device with good properties.

Mitsuya, Masayuki; Suzuki, Takayuki; Koyama, Toshiki; Shirai, Hirofusa; Taniguchi, Yoshio; Satsuki, Makoto; Suga, Sadaharu

2000-11-01

139

Solution-processed organic solar cells from dye molecules: an investigation of diketopyrrolopyrrole:vinazene heterojunctions.  

PubMed

Although one of the most attractive aspects of organic solar cells is their low cost and ease of fabrication, the active materials incorporated into the vast majority of reported bulk heterojunction (BHJ) solar cells include a semiconducting polymer and a fullerene derivative, classes of materials which are both typically difficult and expensive to prepare. In this study, we demonstrate that effective BHJs can be fabricated from two easily synthesized dye molecules. Solar cells incorporating a diketopyrrolopyrrole (DPP)-based molecule as a donor and a dicyanoimidazole (Vinazene) acceptor function as an active layer in BHJ solar cells, producing relatively high open circuit voltages and power conversion efficiencies (PCEs) up to 1.1%. Atomic force microscope images of the films show that active layers are rough and apparently have large donor and acceptor domains on the surface, whereas photoluminescence of the blends is incompletely quenched, suggesting that higher PCEs might be obtained if the morphology could be improved to yield smaller domain sizes and a larger interfacial area between donor and acceptor phases. PMID:22136108

Walker, Bright; Han, Xu; Kim, Chunki; Sellinger, Alan; Nguyen, Thuc-Quyen

2012-01-01

140

The role of the ? linker in donor-?-acceptor organic dyes for high-performance sensitized solar cells.  

PubMed

The key elements arising from different linkers between donor (D) and acceptor (A) fragments in D-?-A organic dyes are computationally studied. Taking triarylamine and the cyanoacrylic acid fragments as donor and acceptor units, respectively, the role of the different separators is computationally explored by means of optimized geometries, frontier molecular orbitals, static polarizabilities and hyperpolarizabilities, excitation energies to the lowest excited singlet, the charge-transfer character of the transition, and simulated absorption spectra. The results are compared to two closely related sets of linkers. Electronic-structure calculations on the studied organic dyes are performed with the CIS(D) wave function based method and time-dependent density functional theory (?B97, ?B97X, and ?PBEh functionals). Solvation effects are introduced with the polarizable continuum model (PCM). PMID:22038881

Casanova, David

2011-11-18

141

Surface Binding and Organization of Sensitizing Dyes on Metal Oxide Single Crystal Surfaces  

SciTech Connect

Even though investigations of dye-sensitized nanocrystalline semiconductors in solar cells has dominated research on dye-sensitized semiconductors over the past two decades. Single crystal electrodes represent far simpler model systems for studying the sensitization process with a continuing train of studies dating back more than forty years. Even today single crystal surfaces prove to be more controlled experimental models for the study of dye-sensitized semiconductors than the nanocrystalline substrates. We analyzed the scientific advances in the model sensitized single crystal systems that preceded the introduction of nanocrystalline semiconductor electrodes. It then follows the single crystal research to the present, illustrating both their striking simplicity of use and clarity of interpretation relative to nanocrystalline electrodes. Researchers have employed many electrochemical, photochemical and scanning probe techniques for studying monolayer quantities of sensitizing dyes at specific crystallographic faces of different semiconductors. These methods include photochronocoulometry, electronic spectroscopy and flash photolysis of dyes at potential-controlled semiconductor electrodes and the use of total internal reflection methods. In addition, we describe the preparation of surfaces of single crystal SnS2 and TiO2 electrodes to serve as reproducible model systems for charge separation at dye sensitized solar cells. This process involves cleaving the SnS2 electrodes and a photoelectrochemical surface treatment for TiO2 that produces clean surfaces for sensitization (as verified by AFM) resulting in near unity yields for electron transfer from the molecular excited dyes into the conduction band.

Parkinson, Bruce

2010-06-04

142

Organic modifier of poly-silicic-ferric coagulant: Characterization, treatment of dyeing wastewater and floc change during coagulation  

Microsoft Academic Search

Organic modifier (PSFD) of poly-silicic-ferric (PSF) coagulant was prepared by adding dimethyldiallylammonium chloride (DMDAAC) as additives in PSF, and was characterized by Scanning Electron Microscopy (SEM), Photon Correlation Spectroscopy (PCS) and Fourier Transform Infrared Spectroscopy (FT-IR). Color removal and floc change during coagulation process in treating a simulated dyeing wastewater by PSFD were investigated compared to those of PSF. The

Fu Ying; Gao Bao-yu; Zhang Yi-feng; Zhang Xin-yu; Shi Nan

2011-01-01

143

Catalytic spectrophotometric determination of trace aluminium with indigo carmine  

NASA Astrophysics Data System (ADS)

A new catalytic spectrophotometric method is described for the determination of trace amounts of Al(III). The methods based on catalytic action of Al(III) on the oxidation of indigo carmine (IC) by ammonium persulfate in hexamethylene tetramine-hydrochloric acid ((CH 2) 6N 4-HCl) buffer medium (pH 5.4) and in the presence of surfactant—TritonX-100. The effects of some factors on the reaction speed were investigated. Aluminium concentration is linear for 0-1.2 × 10 -7 g/ml in this method. The detection limit of the proposed method is 1.96 × 10 -8 g/ml. Most of the foreign ions except for Cu(II), Fe(III) do not interfere with the determination, and the interference of Cu(II) and Fe(III) in this method can be removed by extraction with sodium diethyldithiocarbamate-carbon tetrachloride (DDTC-CCl 4). This system is a quasi-zero-order reaction for Al(III), but it is a quasi-first-order reaction for IC. The apparent rate constant is 2.62 × 10 -5 s -1 and the apparent activation energy is 6.60 kJ/mol in the system. The proposed method was applied to the determination of trace aluminium(III) in real samples with satisfactory results.

Zheng, Huai-Li; Xiong, Wen-Qiang; Gong, Ying-Kun; Peng, De-Jun; Li, Ling-Chun

2007-04-01

144

A copper(I)/copper(II)-salen coordination polymer as a bimetallic catalyst for three-component Strecker reactions and degradation of organic dyes.  

PubMed

A copper(i)/copper(ii)-salen coordination polymer prepared by solvothermal reactions shows prominent bimetallic catalytic activities towards three-component Strecker reactions and photodegradation of organic dyes under visible-light illumination. PMID:24440923

Hou, Yun-Long; Sun, Raymond Wai-Yin; Zhou, Xiao-Ping; Wang, Jun-Hao; Li, Dan

2014-03-01

145

Infrared Dye Laser Study.  

National Technical Information Service (NTIS)

Building on work done in Phase I of this study (See AD-748 863), research on near-infrared dye lasers continued along several lines. Eighteen more Kodak organic dyes were screened for laser action using a linear flash lamp for excitation. Six dyes lased b...

B. E. Plourde J. P. Webb

1973-01-01

146

Organic dye effects on dense nonaqueous phase liquids (DNAPL) entry pressure in water saturated porous media  

NASA Astrophysics Data System (ADS)

Visualization of DNAPL behavior in porous media is generally accomplished using three oil-soluble dyes: SudanIII, SudanIV, or Oil-Red-O. The dyes are generally assumed to not influence that behavior. That assumption was tested in the SudanIV-tetrachloroethene (PCE)-water-glass system. The dye significantly changes surface chemistry as a function of concentration and interface age. PCE mobility increases through lower adhesion tension. Increased mobility was demonstrated using entry pressure experiments for undyed and dyed PCE entering water-saturated glass bead media. Statistically significant entry pressure reduction occurred at a dye concentration of 0.0411 g/L, approximately two orders of magnitude lower than typically used. Dye type, concentration, and surface chemistry are therefore important experimental parameters which should be reported in multiphase flow studies. Dye use increases DNAPL surface chemical complexity, making them reasonable analogs for field DNAPLs. PCE entry pressure was strongly influenced by intrinsic permeability, providing experimental support for Bond number formulations which include permeability.

Tuck, David M.; Iversen, Gary M.; Pirkle, William A.

2003-08-01

147

Preparation of ZnO/Cu2O compound photocatalyst and application in treating organic dyes.  

PubMed

ZnO/Cu(2)O compound photocatalysts were prepared by "soak-deoxidize-air oxidation" with different concentrations of Cu(2+) (0.125, 0.25, 0.5, 1, 1.5 and 2 mol/L). The prepared ZnO/Cu(2)O samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), UV-vis diffuse reflectance spectrometer, and photochemical reaction instrument. The results show that ZnO was hexagonal wurtzite structure and the crystallinity had no change with the increase of Cu(2+) concentration. Cu(2)O belonged to cubic structure and the crystallinity increased with the increase of Cu(2+) concentration. ZnO were rods and bulks which had diameter of about 300-400 nm, some small round Cu(2)O particles which had a diameter of about 50 nm adhered to these rods and bulks. In the compounds the mole ratio of Cu(2)O to ZnO was 0.017, 0.025, 0.076, 0.137, 0.138, and 0.136, respectively. An absorbance in the visible light region between 400 and 610 nm was seen and the reflection rate became less with the mole ratio of Cu(2)O to ZnO increasing. The photocatalytic activities of ZnO/Cu(2)O compound were evaluated using a basic organic dye, methyl orange (MO). It was found that, compared with pure ZnO, the photocatalytic properties of ZnO/Cu(2)O compound were improved greatly and some compounds were better than pure Cu(2)O. PMID:20007008

Xu, Chao; Cao, Lixin; Su, Ge; Liu, Wei; Liu, Hui; Yu, Yaqin; Qu, Xiaofei

2010-04-15

148

Efficiency of energy transfer from organic dye molecules to CdSe-ZnS nanocrystals: nanorods versus nanodots.  

PubMed

We report on comparative experimental study of FRET efficiency in two different systems: organic dye molecules (donors) and CdSe-ZnS core-shell nanodots or nanorods (acceptors). Fluorescein isothiocyanate was bound chemically to the surface of nanocrystals using cysteine as a linker and the conjugates were embedded into the polymeric films. Contrary to intuitive presumptions based on the order of magnitude larger molar absorption coefficient for nanorods, the experiment demonstrated almost equal efficiency in the energy transfer from FITC to nanorods and nanodots. This effect is attributed to a distance-limited region of nanorod to which an efficient FRET from dye molecule can be achieved. These results may pave the way to hybrid materials with FRET efficiency controlled by the geometry of nanocrystals. PMID:19507903

Artemyev, Mikhail; Ustinovich, Elena; Nabiev, Igor

2009-06-17

149

75 FR 81949 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...  

Federal Register 2010, 2011, 2012, 2013

...Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages...Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages...marketers of distilled spirits and importers of wines sold in the United States. The...

2010-12-29

150

Controlling dye (Merocyanine-540) aggregation on nanostructured TiO{sub 2} films. An organized assembly approach for enhancing the efficiency of photosensitization  

SciTech Connect

The anionic cyanine dye Merocyanine 540 (MC540) dissolved in Aerosol-OT (AOT) solutions of heptane and toluene possesses a significantly higher fluorescence quantum yield and excited singlet lifetime than the acetonitrile solutions of the dye. The difference in the photophysical properties observed upon incorporation of the dye into the AOT micelles is attributed to the decrease in the photoisomerization efficiency. The presence of AOT also controls the aggregation and photosensitization behavior of MC540 adsorbed onto TiO{sub 2} semiconductor nanoparticles. MC540 adsorbed onto nanostructured TiO{sub 2} films from acetonitrile solutions contains both the aggregated and monomeric forms of the sensitizer, while the dye-modified films obtained from AOT/heptane solutions contain mainly the monomeric form of the sensitizer. Significant enhancement in the photocurrent generation efficiency has been achieved in photoelectrochemical cells using the AOT encapsulated dye films. An electroactive polymer (poly(4-vinylpyridine)) film cast on the dye-modified TiO{sub 2} electrode has been found to be effective in promoting charge mediation and minimizing dye desorption from the electrode surface. The incident photon-to-photocurrent generation efficiency (IPCE) exhibited by the monomeric form ({approximately}40%) is nearly five times greater than the corresponding efficiency of the aggregate form ({approximately}8%). The beneficial aspects of incorporating dyes in organized assemblies for the purpose of suppressing nonradiative decay of the excited-state sensitizer and minimizing the aggregation effects on semiconductor surfaces are discussed.

Khazraji, A.C. [Notre Dame Radiation Lab., IN (United States)] [Notre Dame Radiation Lab., IN (United States); [Univ. du Quebec a Trois-Rivieres (Canada). Groupe de Recherche en Energie et Information Biomoleculaires; Hotchandani, S. [Univ. du Quebec a Trois-Rivieres (Canada). Groupe de Recherche en Energie et Information Biomoleculaires] [Univ. du Quebec a Trois-Rivieres (Canada). Groupe de Recherche en Energie et Information Biomoleculaires; Das, S.; Kamat, P.V. [Notre Dame Radiation Lab., IN (United States)] [Notre Dame Radiation Lab., IN (United States)

1999-06-03

151

An integrated experimental and theoretical approach to the spectroscopy of organic-dye-sensitized TiO? heterointerfaces: disentangling the effects of aggregation, solvation, and surface protonation.  

PubMed

We report a joint experimental and computational study into the spectroscopic properties of a prototypical D5 organic dye, both in solution and adsorbed on a TiO2 surface, with the aim of modeling and quantifying the UV/Vis spectral shifts that occur in the different explored environments. Going from the dye in solution to dye-sensitized TiO2, various factors may shift the position of the UV/Vis absorption maximum, both towards longer and shorter wavelengths. Here we have focused on the effect of dye aggregation on TiO2, surface protonation, and solvent effects. The D5 dye forms stable aggregates on the TiO2 surface that cause spectral blueshifts. We used different sensitization conditions to vary the dye loading and thus the extent of dye aggregation. For each sensitization condition, we explored protonated and native TiO2 films. Computational modeling of different dimeric aggregates with increasing intermolecular interactions and simulation of the associated optical responses also confirm the observed spectral blueshifts. Our results show that both the presence of surface protons and solvent stabilize the excited state of the adsorbed dye molecules, which causes a marked redshift in the absorption maximum and thus moves in the opposite direction to the shift due to the increase in the surface coverage. PMID:24402779

Marotta, Gabriele; Lobello, Maria Grazia; Anselmi, Chiara; Barozzino Consiglio, Gabriella; Calamante, Massimo; Mordini, Alessandro; Pastore, Mariachiara; De Angelis, Filippo

2014-04-14

152

Tailoring of organic dyes with oxidoreductive compounds to obtain photocyclic radical generator systems exhibiting photocatalytic behavior  

PubMed Central

Summary The combination of a dye which absorbs the photon, an electron acceptor and an electron donor leading to energy conversion through electron transfer, was the basis of the so called three-component systems. In this paper, an experimental work combining Rose bengal dye with a triazine derivative as electron acceptor and ethyl 4-(dimethylamino)benzoate as electron donor, will underline the benefit of the photocyclic behavior of three-component systems leading to the dye regeneration. A thermodynamic approach of the photocycle is presented, followed by a mechanistic and computational study of ideal photocycles, in order to outline the specific kinetics occuring in so called photocatalytic systems. The simple kinetic model used is enough to outline the benefit of the cyclic system and to give the basic requirements in term of chemical combination needed to be fulfilled in order to obtain a photocatalytic behavior.

Christmann, Julien; Ibrahim, Ahmad; Stefano, Luciano H Di; Allonas, Xavier

2014-01-01

153

Clickable Degradable Aliphatic Polyesters via Copolymerization with Alkyne Epoxy Esters: Synthesis and Postfunctionalization with Organic Dyes.  

PubMed

Degradable aliphatic polyesters are the cornerstones of nanoparticle (NP)-based therapeutics. In this paradigm, covalent modification of the NP with cell-targeting motifs and dyes can aid in guiding the NP to its destination and gaining visual confirmation. Therefore, strategies to impart chemistries along the polymer backbone that are amenable to easy modification, such as 1,3-dipolar cycloaddition of an azide to an alkyne (the "click reaction"), could be significant. Here we present a simple and efficient way to introduce alkyne groups at high density in aliphatic polyesters without compromising their crystallinity via the copolymerization of cyclic lactones with propargyl 3-methylpentenoate oxide (PMPO). Copolymers of lactic acid and ?-caprolactone with PMPO were synthesized with up to 9 mol % alkyne content, and accessibility of the alkyne groups to the click reaction was demonstrated using several dyes commonly employed in fluorescence microscopy and imaging (Cy3, ATTO-740, and coumarin 343). In order to establish the suitability of these copolymers as nanocarriers, copolymers were formulated into NPs, and cytocompatibility, cellular uptake, and visualization studies undertaken in HeLa cells. Dye-modified NPs exhibited no quenching, remained stable in solution for at least 10 days, showed no cytotoxicity, and were readily taken up by HeLa cells. Furthermore, in addition to enabling the incorporation of multiple fluorophores within the same NP through blending of individual dye-modified copolymers, dye-modified polyesters offer advantages over physical entrapment of dye, including improved signal to noise ratio and localization of the fluorescence signal within cells, and possess the necessary prerequisites for drug delivery and imaging. PMID:24972035

Teske, Nele S; Voigt, Julia; Shastri, V Prasad

2014-07-23

154

Electrochromism and Solvatochromism in Fluorescence Response of Organic Dyes: A Nanoscopic View  

Microsoft Academic Search

\\u000a \\u000a Abstract  Methods are described that allow prediction and understanding of solvatochromism and fluorescence quenching of dyes embedded\\u000a in a nanometer-scale medium, e.g., solvent, protein, and membranes. Spectra of the dye are calculated at the microscopic level\\u000a using quantum mechanics coupled to the point charges representing the medium by Coulombic potentials, while the whole system\\u000a propagates by classical molecular mechanics. This view

Patrik R. Callis

155

Multi-Layered Anisotropic Films Based on the Azo Dye Brilliant Yellow and Organic Polymers  

NASA Astrophysics Data System (ADS)

A technique for producing multi-layered fi lms containing alternating layers of photo-aligned dichroic azo dye brilliant yellow (BY) dispersed in a matrix of polyvinylpyrrolidone and optically transparent polycyclohexadiene (PCHD) was developed. The optical density of the films depended linearly on the number of layers of dye and its concentration in the initial solutions. It was determined that the surface roughness of the composition BY layer on the PCHD layer was three times less than on single-crystalline silicon substrate (4.8 and 1.5 nm). Multi-layered fi lms based on BY exhibited dichroic absorption and birefringence upon irradiation with linearly polarized light (? = 450 nm).

Chaplanova, Zh. D.; Murauski, A. A.; Rogachev, A. A.; Agabekov, V. E.; Gracheva, E. A.

2013-11-01

156

Nonlinear optical organic co-crystals of merocyanine dyes and phenolic derivatives with short hydrogen bonds  

Microsoft Academic Search

We investigated the co-crystallization of merocyanine dyes M (M: R–N+C5H4–CH?CH–C6H4O?, M1: R=CH3, M2: R=HO–CH2–CH2–) with phenolic and aniline derivatives and show that the short or very short hydrogen bond between the two phenolic oxygen atoms which lead to a self-assembly of the M dyes and phenol derivatives is the key steering force for the co-crystallization process. The co-crystal formation was

Christian Bosshard; Feng Pan; Man Shing Wong; Sabine Manetta; Rolf Spreiter; Chengzhi Cai; Peter Günter; Volker Gramlich

1999-01-01

157

Response characterization of a fiber optic sensor array with dye-coated planar waveguide for detection of volatile organic compounds.  

PubMed

We have developed a multi-array side-polished optical-fiber gas sensor for the detection of volatile organic compound (VOC) gases. The side-polished optical-fiber coupled with a polymer planar waveguide (PWG) provides high sensitivity to alterations in refractive index. The PWG was fabricated by coating a solvatochromic dye with poly(vinylpyrrolidone). To confirm the effectiveness of the sensor, five different sensing membranes were fabricated by coating the side-polished optical-fiber using the solvatochromic dyes Reinhardt's dye, Nile red, 4-aminophthalimide, 4-amino-N-methylphthalimide, and 4-(dimethylamino)cinnamaldehyde, which have different polarities that cause changes in the effective refractive index of the sensing membrane owing to evanescent field coupling. The fabricated gas detection system was tested with five types of VOC gases, namely acetic acid, benzene, dimethylamine, ethanol, and toluene at concentrations of 1, 2,…,10 ppb. Second-regression and principal component analyses showed that the response properties of the proposed VOC gas sensor were linearly shifted bathochromically, and each gas showed different response characteristics. PMID:24988381

Lee, Jae-Sung; Yoon, Na-Rae; Kang, Byoung-Ho; Lee, Sang-Won; Gopalan, Sai-Anand; Jeong, Hyun-Min; Lee, Seung-Ha; Kwon, Dae-Hyuk; Kang, Shin-Won

2014-01-01

158

Hair dye use and occupational exposure to organic solvents as risk factors for myelodysplastic syndrome  

Microsoft Academic Search

To investigate the relationships of personal hair dye use and environmental factors to myelodysplastic syndromes (MDS), we conducted a case-control study in Japan. A total of 111 MDS cases and 830 controls randomly selected from the residents in the same prefecture of cases using telephone directories responded to a health questionnaire. The odds ratio (OR) for ever having used hair

Chisato Nagata; Hiroyuki Shimizu; Kunitake Hirashima; Eizo Kakishita; Kingo Fujimura; Yoshiyuki Niho; Masamitsu Karasawa; Shigeru Oguma; Yataro Yoshida; Hideaki Mizoguchi

1999-01-01

159

Solvent-induced organization of squaraine dyes in solution capillary layers and adsorbed films.  

PubMed

Unusual behavior of indolenine and hydroxyphenyl squaraines has been observed in solution capillary layers and adsorbed films. The confined solutions showed anomalous aggregation of squaraine molecules in contrast to their monomer behavior in the bulk solutions of the same concentration, along with formation of a macroscopic cell-like structure in the confined solution layer, with the diameter of cells being 3-5 microm. The aggregate structure, as observed through electronic absorption spectra, was strongly dependent on the chemical structure of squaraine used and solvent used, and it also was different from squaraine aggregates observed in aqueous solutions and films prepared by vacuum evaporation. It has been found that indolenine squaraine is capable of forming H-aggregates in confined dimethylformamide solutions and hydroxyphenyl squaraine is capable of forming J-aggregates in confined dimethylformamide solutions and adsorbed films. The results were compared with pseudoisocyanine, which forms J-aggregates in aqueous bulk solutions readily; however, no J-aggregates have been found in their capillary layers. The interplay of dye-dye, dye-surface, and dye-solvent interactions resulting in the above effects is discussed. PMID:16851533

Dimitriev, O P; Dimitriyeva, A P; Tolmachev, A I; Kurdyukov, V V

2005-03-17

160

Removal of organic dyes by UV/H2O2 process: modelling and optimization.  

PubMed

The effects of different operational parameters on the decolorization of a dye solution containing C.I. Acid Blue 92 (AB92) or C.I. Acid Black 1 (AB1) by the UV/H2O2 process were optimized using response surface methodology (RSM). The reaction time, dye and H2O2 initial concentrations and distance of the UV lamp from the solution were chosen as input variables. The removal process was performed according to a central composite design. Predicted results by the proposed models were in good agreement with experimental values (R2 = 0.942 and 0.957 for AB92 and AB1, respectively). The optimum points were located by graphical response surfaces and contour plots. The removal process of the dyes was compared and the efficiency difference justified by considering the chemical structure of the dyes. Additionally, the electrical energy consumption and the related treatment costs were estimated employing the figure-of-merit electrical energy per order (E(EO)). PMID:22856317

Kasiri, M B; Khataee, A R

2012-06-01

161

Enhanced Fluorescence of Quantum Dots by Au Nanoparticles on MultiColor Silica Spheres Labeled with Organic Dyes and Quantum Dots  

Microsoft Academic Search

We have prepared the multi-color hybrid silica spheres by assembling CdSe\\/ZnS quantum dots (QDs) on the organic dye-doped silica spheres. The labeled silica spheres can be excited simultaneously and exhibit dual luminescent emissions corresponding to the dyes and QDs, respectively. The fluorescence of QDs can be selective enhanced by Au nanoparticles, and the fluorescence intensity ratio of the dual emissions

Xian Zhang; Min Li; Xiao-Niu Peng; Li Zhou

2009-01-01

162

A dye-sensitized Pt@UiO-66(Zr) metal-organic framework for visible-light photocatalytic hydrogen production.  

PubMed

A stable photoactive metal-organic framework UiO-66(Zr) sensitized by adsorbed or directly added rhodamine B dye exhibited photocatalytic activity for hydrogen evolution under visible-light illumination (?? 420 nm). Using Pt as a co-catalyst, the adsorbed and directly added dye extremely enhanced the photocatalytic activity to 30 and 26 times the value afforded by bare Pt@UiO-66(Zr), respectively. PMID:24848342

He, Jiao; Wang, Jiaqiang; Chen, Yongjuan; Zhang, Jinping; Duan, Deliang; Wang, Yao; Yan, Zhiying

2014-07-01

163

Total colonic dye-spray increases the detection of diminutive adenomas during routine colonoscopy: A randomized controlled trial  

Microsoft Academic Search

Background: Small adenomas may be missed during colonoscopy, but chromoscopy has been reported to enhance detection. The aim of this randomized-controlled trial was to determine the effect of total colonic dye spray on adenoma detection during routine colonoscopy. Methods: Consecutive outpatients undergoing routine colonoscopy were randomized to a dye-spray group (0.1% indigo carmine used to coat the entire colon during

Jim C. Brooker; Brian P. Saunders; Syed G. Shah; Catherine J. Thapar; Huw J. W. Thomas; Wendy S. Atkin; Christopher R. Cardwell; Christopher B. Williams

2002-01-01

164

Solid-state dye-sensitized photovoltaic device with newly designed small organic molecule as hole-conductor  

Microsoft Academic Search

A newly and interestingly small organic molecule, (R)-2,2?-dimethoxyl-3,3?-di(phenyl-4-yl-diphenyl-amine)-[1,1?]-binaphthyl, was introduced into solid-state electrolyte to assemble dye-sensitized photoelectrical cell. With optimized molecular structure and composite porous TiO2 electrode, the solid-state device without any additives in electrolyte converted light to electric efficiency with a 0.07%. Under the assistance of some functional small-molecules in the electrolyte, solid-state devices showed an attractive conversion efficiency

Yong Zhao; Wei Chen; Jin Zhai; Xianliang Sheng; Qingguo He; Tianxin Wei; Fenglian Bai; Lei Jiang; Daoben Zhu

2007-01-01

165

Influences of Electron-Withdrawing Groups of Organic Dyes on Spectral Property and Photovoltaic Performance in Dye-sensitized Solar Cells Application  

NASA Astrophysics Data System (ADS)

We synthesized five donor--?-spacer--acceptor type organic photosensitizers bearing different types of electron-withdrawing groups (EWGs); trifluoromethyl, o-nitrophenyl, p-nitrophenyl, cyano, and carboxyl groups, on their acceptor part in the aim of observing an influence of the EWGs on spectral and photovoltaic properties from viewpoints of steric structure and ?-conjugation. The EWG possessing smaller dihedral angle between the EWG and dye skeleton exhibited larger bathochromic shift in absorptions. Highly planer cyano group presented the most red-shifted absorption at 464 nm, and the highest conversion efficiency of 5.69% was obtained. In contrast, highly distorted o- and p-nitrophenyl groups exhibited blue-shifted absorption at 416 and 422, respectively; however, despite of resemble spectral properties, o- and p-nitrophenyl gave second best and the worst conversion efficiencies of 4.05 and 2.51%, respectively. By combination with computational chemistry, it was indicated that the configuration of the EWG and distance between TiO2 surface and the EWG dominated electron injection efficiency.

Numata, Youhei; Han, Liyuan

2012-10-01

166

High-performance dye-sensitized solar cells containing double-layer organized mesoporous TiO2 films sensitized by a dye with a high molar extinction coefficient  

NASA Astrophysics Data System (ADS)

In the present work, we describe a practical technique to construct double-layer organized mesoporous TiO2 films with a combined thickness of 0.85 ?m. Large mesopores (25.74 nm) formed in the film by using ovalbumin as the main template facilitate entry and adsorption of dye molecules. The films were sensitized by a dye that exhibits a high molar extinction coefficient because it contains a ligand with a fused-ring system. The double-layer films exhibited a solar conversion efficiency of 7.37%, which was about 35% higher than that of monolayer films.

Wang, Juangang; Shang, Yunli

2013-04-01

167

Random lasing in liquid and solid solutions oversaturated with organic laser dye  

NASA Astrophysics Data System (ADS)

We present the results of studies carried out for oversaturated solutions with common laser dye 4- (Dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM) and 3-(1,1-Dicyanoethenyl)-1-phenyl-4,5- dihydro-1H-pyrazole (DCNP) nonlinear chromophore. We show that oversaturating the solution leads to formation of crystals suspension resulting in strong Mie scattering and thus random laser operation can be observed. The formation of aggregates can be induced be oversaturating the solution or by injection of non-solvent to the dye solution, leading to reduction of solubility limit. Similar situation can be obtained for polymeric matrices for which small crystals are precipitated during layer formation (solvent evaporation) when film is casted from the solution.

Sznitko, Lech; Cyprych, Konrad; Szukalski, Adam; Miniewicz, Andrzej; Mysliwiec, Jaroslaw

2014-03-01

168

Stimulated emission and lasing in dye-doped organic thin films with Forster transfer  

SciTech Connect

Optically pumped stimulated emission and lasing in thin films of an absorbing host 8-hydroxyquinolinato aluminum(Alq) doped with small amounts of the laser dye DCM II is observed. Forster transfer of the excitation from the Alq molecules to the DCM II molecules results in a high absorption coefficient at pump wavelength (337 nm) as well as low absorption loss at the emission wavelengths (610{endash}650 nm). {copyright} {ital 1997 American Institute of Physics.}

Berggren, M.; Dodabalapur, A.; Slusher, R.E. [Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, New Jersey 07974 (United States)] [Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, New Jersey 07974 (United States)

1997-10-01

169

A Unified Description of Linear and Nonlinear Polarization in Organic Polymethine Dyes  

Microsoft Academic Search

An internal or external electric field F can drive the chemical structure, bond order alternation, and electronic structure of linear polymethine dyes from a neutral, bond-alternated, polyene-like structure, through a cyanine-like structure, and ultimately to a zwitterionic (charge-separated) bond-alternated structure. As the structure evolves under the influence of F, the linear polarizability alpha, the first hyperpolarizability beta, and the second

Seth R. Marder; Christopher B. Gorman; Fabienne Meyers; Joseph W. Perry; Grant Bourhill; Jean-Luc Bredas; Brian M. Pierce

1994-01-01

170

Fast assembly of cyanine dyes into aggregates onto [6,6]-phenyl C61-butyric acid methyl ester surfaces from organic solvents.  

PubMed

Supramolecular agglomerates of organic colorants based on noncovalent interactions are promising candidates for the development of sensors, optoelectronics, lighting, or photovoltaics. However, their fast and defect-free fabrication on large scales using low-cost technologies has proven elusive so far. Here, we introduce a so far unreported mechanism to induce molecular order in cyanine dyes within minutes from organic solvents by self-assembly. Spin coating blends of a cyanine dye and a soluble fullerene derivative ([6,6]-phenyl C(61)-butyric acid methyl ester (PCBM)) from apolar, aprotic solvents leads to phase-separated structures on the micrometer scale. With this superordinated phase structure, adjustment of dye aggregation is possible, leading to novel optical properties of the film emerging from dye self-assembly on the nanometer scale. In the primary process, semiporous PCBM domains act as nucleation sites for H-aggregates. H-aggregates can then be reconstructed into J-aggregates by dissolving PCBM from the film. Unexpectedly, the method even works for sterically hindered cyanine dyes that are known for their reduced tendency to aggregate. Additionally, selective removal of H-aggregates leaves a template of PCBM nanocrystals, onto which cyanine dye monomers readsorb from solution, forming H-aggregates of similar quality. PMID:20073528

Heier, Jakob; Steiger, Rolf; Nüesch, Frank; Hany, Roland

2010-03-16

171

Stimulated resonance Raman scattering from organic dyes in a multiple-scattering medium as a potential method for determining their vibrational spectra  

SciTech Connect

A method is described for deriving Raman spectra of organic dyes from their random lasing spectra. The method was tested using Rhodamine 6G. The Raman spectrum obtained for this dye agrees well with the spectra measured by standard techniques but is more structured, which allows unresolved features to be detected. The spectrum provides more detailed information owing to the interference between the Raman scattered light and amplified spontaneous emission of the dye molecules within a photon mean free path. One advantage of the method is that the luminescence of the dye helps to observe Raman lines, which allows one to work in the Stokes region and facilitates the measurement procedure. (nonlinear optical phenomena)

Yashchuk, V P; Tikhonov, E A; Bukatar', A O; Prigodiuk, O A; Smalyuk, A P

2011-10-31

172

Smectite clays of Serbia and their application in adsorption of organic dyes  

NASA Astrophysics Data System (ADS)

Colorants and dyes are currently available in over a 100.000 different species and several biggest industries are using them daily in their manufacture processes (textile, cosmetics, food industry, etc.). Since colorants are easily dissoluble in water they pass through filter membranes without further decomposing and in that manner they end up in the environment. The main goal of this work is to apply certain methods in determining the suitability of individual clay in adsorbing and removing colorants from polluted waters. For this study we have chosen four different raw clays from three regions in Serbia: Svrljig (B), Bogovina (Bo) and Slatina-Ub (C and V) and as colorant - methylene blue dye (MB (MERCK, for analytical purposes)). Experiments where carried out to determine the sample structure (XRD and IR), grain size (granulometry), cationic exchange capacity (CEC via spectrophotometry using MB) and adsorption capabilities (spectrophotometry and fluorimetry using MB). XRD and IR data are showing that the samples are smectite clays where samples B i Bo are mainly montmorillonite while C and V are montmorillonite-illite clays. Granulometric distribution results indicate that samples B i Bo have smaller grain size, less that 1? (over 60%) whereas the samples C and V are more coarse grained (40% over 20?). This grain distribution is affecting their specific surface area in the manner that those coarse grained samples have smaller specific surface area. Cationic exchange capacity determined with methylene blue indicate that montmorillonite samples have larger CEC (B = 37 meq/100g, Bo = 50 meq/100g) and montmorillonite-illite samples smaller CEC (V = 5 meq/100g, V = 3 meq/100g). Fluorimetry measurement results gave us a clear distinction between those with higher and smaller adsorption capability. Montmorillonite samples (B and Bo) with higher CEC values and smaller grain size are adsorbing large amounts of methylene blue witch is visible by absence of fluorimetric band corresponding to methylene blue. Montmorillonite-illite samples with smaller CEC values and coarser grain size are adsorbing very small amounts of methylene blue from the suspension which is visible by appearance of the methylene blue band. Untreated, raw smectite clays of Serbia are efficient adsorbent material for removal of dyes from polluted waters. Samples from two regions especially, Bogovina and Svrljig, are showing favorable adsorption results and they are representing good raw materials for purification of waste-waters containing dyes. References: - Jovi?-Jovi?i?, N., Milutinovi?-Nikoli?, A., Gržeti?, I., Jovanovi?, D.; Organobentonite as efficient textile dye sorbent; Chem. Eng. Technol. 2008, 31, No. 4, 567-574 - Žuni?, M.J., Milutinovi?-Nikoli?, A.D., Jovi?-Jovi?i?, N.P., Bankovi?, P.T., Mojovi?, Z.D., Manojlovi?, D.D., Jovanovi?, D.M.; Modified bentonite as adsorbent and catalyst for purification of wastewaters containing dyes; Hem. ind. 2010, 64 ,No. 3, 193-199

Miloševi?, Maja; Logar, Mihovil

2014-05-01

173

UV light induced photodegradation of organic dye by ZnO nanocatalysts  

NASA Astrophysics Data System (ADS)

Ultraviolet light induced photocatalytic activity of ZnO nanocatalyst prepared using a wet chemical precipitation route and mineralization of the methyl orange (MO) dye has been carried out in a photocatalytic reactor. The degradation of the MO was monitored spectrophotometrically and showed a decolorization efficiency of 92% after nine hours of irradiation in the MO-ZnO/UV light system. The blue shifting of maximum peak position of the MO and the formation of extra peak at 247 nm during irradiation time advances revealed that MO degrades in the form of intermediates during the photocatalytic process.

Sumesh, C. K.; Patel, Bhavin; Parekh, Kinnari

2013-06-01

174

UV light induced photodegradation of organic dye by ZnO nanocatalysts  

SciTech Connect

Ultraviolet light induced photocatalytic activity of ZnO nanocatalyst prepared using a wet chemical precipitation route and mineralization of the methyl orange (MO) dye has been carried out in a photocatalytic reactor. The degradation of the MO was monitored spectrophotometrically and showed a decolorization efficiency of 92% after nine hours of irradiation in the MO-ZnO/UV light system. The blue shifting of maximum peak position of the MO and the formation of extra peak at 247 nm during irradiation time advances revealed that MO degrades in the form of intermediates during the photocatalytic process.

Sumesh, C. K.; Patel, Bhavin [Department of Physical Sciences, P.D. Patel Institute of Applied Sciences, CHARUSAT, Changa-388 421, Gujarat (India); Parekh, Kinnari [Dr. K. C. Patel R and D Centre, CHARUSAT, Changa-388 421, Gujarat (India)

2013-06-03

175

Properties of two-photon fluorescence and superradiance of a new organic dye C46H51N2B  

NASA Astrophysics Data System (ADS)

Linear and nonlinear optical properties of a new organic dye, trans-4-[ p-(N-n-butyl-N-n-butylamino)-styryl] -N-methyl-pyridinium tetraphenylborate solution in dimethyl formamide (DMF) have been studied systematically. When excited with mode-locked picosecond 1 064 nm laser beam, intense upconversion fluorescence and superradiance can be obtained. The temporal behaviors of one-photon absorption and two-photon absorption (TPA) fluorescence and superradiance have been studied. The highest upconversion efficiency was found to be 4.1% at a pump energy of 4 mJ. By using an optical parameter amplifier (OPA) as the pump laser, the nonlinear transmittance and upconversion efficiencies of the dye solution at different wavelengths were measured. The strongest linear absorption was found at a wavelength of 930 nm whereas the highest upconversion efficiency was at 1 030 nm. The 100 nm red-shift for the highest upconversion efficiency wavelength compared with the strongest nonlinear absorption are caused by excited state absorption.

Zhou, G.; Wang, D.; Yang, S.; Ren, Y.; Xu, X.; Shao, Z.; Zhao, X.; Jiang, M.; Tian, Y.; Hao, F.; Li, S.; Shi, P.

2002-06-01

176

Electrodeposited ZnO nanowires as photoelectrodes in solid-state organic dye-sensitized solar cells.  

PubMed

A new approach for developing solid-state dye-sensitised solar cells (DSSCs) on glass/ITO and plastic substrates (PEN/ITO) is presented in this manuscript. A two step electrodeposition technique has been employed to realize the ZnO photoelectrodes. First a ZnO thin film is deposited on the ITO substrate and subsequently on this buffer layer 650 nm long ZnO nanowires are grown. The different nanostructured electrodes are crystallized and show a transparency close to 80% in the visible spectral range. The electrodes are then sensitized with a new purely organic dye, whose synthesis is presented here, which reveals a wide absorption spectrum and a high molar extinction coefficient. Finally, the sensitized electrodes were employed for the fabrication of liquid and solid-state DSSCs, using, respectively, a liquid iodine/iodide electrolyte and the spiro-OMeTAD hole transporter. These devices represent the first solid-state DSSCs fabricated using electrodeposited zinc oxide nanowires. Their power conversion efficiency is still limited, respectively, 0.18% and 0.03% under standard AM 1.5G sunlight (100 mW cm(-2)), nevertheless, these results prove the interest in this low-temperature deposition method for the realization of nanostructured electrodes on rigid and flexible substrates, and open up new perspectives for the development of solid state DSSCs on plastic substrates. PMID:24626609

Muguerra, Hervé; Berthoux, Gaëlle; Yahya, Wan Zaireen Nisa; Kervella, Yann; Ivanova, Valentina; Bouclé, Johann; Demadrille, Renaud

2014-04-28

177

Organic dye lasers with distributed Bragg reflector grating and distributed feedback resonator.  

PubMed

The paper presents polymeric waveguide dye laser with distributed Bragg reflector (DBR) grating or distributed feedback (DFB) resonator. DBR grating and DFB resonator were fabricated on a surface of SU-8 2002 photoresist polymer using interference of laser beams. Polystyrene (PS) and poly(vinyl butyral) (PVB) waveguides dispersed with laser dye of 3-(2-benzothiazolyl)-7-(diethylamino)-coumarin (Coumarin 6) and tris(8-quinolinolate)aluminum (Alq) as a host were used. Single mode of lasing with TE mode was measured from the polymeric waveguide with DBR grating and DFB resonator. Threshold of lasing with DBR grating is lower than that with DFB resonator. For PVB/Alq/Coumarin 6 waveguide, 0.1 mJ cm(-2) pulse(-1) of threshold was measured with DBR grating and 0.3 mJ cm(-2) pulse(-1) with DFB resonator. Slope efficiency between 0.06 and 0.09 % was measured for PS/Alq/Coumarin 6 waveguide and that between 0.07 and 0.15 for PVB /Alq/Coumarin 6 waveguide. PMID:19997411

Tsutsumi, Naoto; Ishibashi, Takashi

2009-11-23

178

Theoretical studies on organic D-?-A sensitizers with planar triphenylamine donor and different ?-linkers for dyes-sensitized solar cells.  

PubMed

Systematic density functional theory (DFT) and time-dependent DFT calculations on the geometry, electronic structure, absorption, and nonlinear optical (NLO) properties of experimentally synthesized organic sensitizers LCn (n?=?1-3) used in dyes-sensitized solar cells (DSSCs) were performed to disclose the important influences of the planar triphenylamine donor and the extended ?-linker on the DSSCs performance. The interaction of dye with I2 and the conduction band shift were also investigated to rationalize the difference in open-circuit photovoltage (V oc). The results demonstrated that the planarization of TPA donor and the extended conjugation of ?-linker in sensitizers LC2 and LC3 could result in a red shift of absorption and a reduction in exciton binding energy, which is beneficial to enhance the matching degree of absorption of sensitizers with solar photon-flux spectrum and to improve the incident photon-to-current conversion efficiency, both contributing to the significant increase of photocurrent density as compared to reference dye LC1. It is also found that the calculated NLO properties correlated well with the photocurrent response of sensitizers, suggesting that NLO properties may be used as an effective tool for the fast screen and design of candidate sensitizers. As for candidate dyes Tn (n?=?1-4) with different dithiophene blocks as ?-linker, dye T1 with dithienosilole as ?-linker may serve as a promising alternative to high-performance dye LC3. PMID:24961897

Li, Hai-Bin; Zhang, Jian-Zhao; Zhang, Ji; Wu, Yong; Duan, Yi-Ai; Su, Zhong-Min; Geng, Yun

2014-07-01

179

Removal of organic polycyclic compounds from water solutions with a magnetic chitosan based sorbent bearing copper phthalocyanine dye  

Microsoft Academic Search

Magnetic chitosan gel particles, bearing covalently immobilized copper phthalocyanine dye (“magnetic blue citosan”), were prepared and used for the isolation and\\/or removal of polycyclic dyes from water solutions and suspensions. Binding of these polycyclic dyes occures by a chemical equilibrated and saturatable mechanism, following the Langmuir adsorption model. The values of maximum uptake (maximum adsorption capacity) were calculated. The bound

Ivo Šafa?ík

1995-01-01

180

ZnO-based dye solar cell with pure ionic-liquid electrolyte and organic sensitizer: the relevance of the dye–oxide interaction in an ionic-liquid medium.  

PubMed

The use of non-volatile electrolytes and fully organic dyes are key issues in the development of stable dye-sensitized solar cells (DSCs). In this work we explore the performance of ZnO-based DSCs sensitized with an indoline derivative coded D149 in the presence of a pure ionic-liquid electrolyte. Commercial nanostructured zinc oxide and an electrolyte composed of iodine plus (1) pure 1-propyl-3-methyl imidazolium iodide (PMII) and (2) a blend of PMII with low-viscosity ionic liquids were employed to construct the devices. Without further additives, the fabricated devices exhibit remarkable short-circuit photocurrents and efficiencies under AM1.5 simulated sunlight (up to 10.6 mA cm?2, 2.9% efficiency, 1 sun, active area = 0.64 cm2) due to the high surface area of the ZnO film and the high absorptivity of the D149 dye. Impedance spectroscopy is used to characterize the devices. It is found that the addition of the low-viscosity ionic-liquid improves the transport features (leading to a better photocurrent) but it does not alter the recombination rate. The robustness of the dye–oxide interaction is tested by applying continuous illumination with a Xenon-lamp. It is observed that the photocurrent is reduced at a slow rate due to desorption of the D149 sensitizer in the presence of the ionic liquid. Exploration of alternative ionic-liquid compositions or modification of the ZnO surface is therefore required to make stable devices based on ZnO and fully organic dyes. PMID:21188845

Guillén, E; Idígoras, J; Berger, T; Anta, J A; Fernández-Lorenzo, C; Alcántara, R; Navas, J; Martín-Calleja, J

2011-01-01

181

Infrared Dye Laser Study.  

National Technical Information Service (NTIS)

Near infrared laser action has been demonstrated for 9 Kodak organic dyes, using a linear flash lamp for excitation. The spectral region covered by these 9 dyes extends from 850 nm to at least 960 nm, with no tuning attempted so far. Output is in the kilo...

B. E. Plourde J. P. Webb

1972-01-01

182

Carrier multiplication in semiconductor nanocrystals detected by energy transfer to organic dye molecules  

PubMed Central

Carrier multiplication describes an interesting optical phenomenon in semiconductors whereby more than one electron-hole pair, or exciton, can be simultaneously generated upon absorption of a single high-energy photon. So far, it has been highly debated whether the carrier multiplication efficiency is enhanced in semiconductor nanocrystals as compared with their bulk counterpart. The controversy arises from the fact that the ultrafast optical methods currently used need to correctly account for the false contribution of charged excitons to the carrier multiplication signals. Here we show that this charged exciton issue can be resolved in an energy transfer system, where biexcitons generated in the donor nanocrystals are transferred to the acceptor dyes, leading to an enhanced fluorescence from the latter. With the biexciton Auger and energy transfer lifetime measurements, an average carrier multiplication efficiency of ~17.1% can be roughly estimated in CdSe nanocrystals when the excitation photon energy is ~2.46 times of their energy gap.

Xiao, Jun; Wang, Ying; Hua, Zheng; Wang, Xiaoyong; Zhang, Chunfeng; Xiao, Min

2012-01-01

183

Blue-Light-Emitting Organic Electroluminescent Devices with Oxadiazole Dimer Dyes as an Emitter  

NASA Astrophysics Data System (ADS)

Multilayer thin-film electroluminescent devices with blue emission color have been fabricated using new oxadiazole dimer dyes for both emission and electron transport layers. Emission characteristics of three types of cells, SH-A: ITO/HTL/EML/MgAg, SH-B: ITO/EML/ETL/MgAg and DH: ITO/HTL/EML/ETL/MgAg, in which ITO, HTL, EML, ETL and MgAg represent indium-tin-oxide cathode, hole transport layer, emission layer, electron transport layer and magnesium-silver alloy anode, respectively, are compared. Luminances exceeding 1000 cd/m2 are observed and emission peaks are located at 470-480 nm. Among the three cells, the DH cell shows the best performance. The DH cell is stable for more than 40-day storage and can also be continuously driven for more than one hour at room temperature and 7 h at liquid nitrogen temperature.

Hamada, Yuji; Adachi, Chihaya; Tsutsui, Tetsuo; Saito, Shogo

1992-06-01

184

Polariton-mediated energy transfer between organic dyes in a strongly coupled optical microcavity.  

PubMed

Strongly coupled optical microcavities containing different exciton states permit the creation of hybrid-polariton modes that can be described in terms of a linear admixture of cavity-photon and the constituent excitons. Such hybrid states have been predicted to have optical properties that are different from their constituent parts, making them a test bed for the exploration of light-matter coupling. Here, we use strong coupling in an optical microcavity to mix the electronic transitions of two J-aggregated molecular dyes and use both non-resonant photoluminescence emission and photoluminescence excitation spectroscopy to show that hybrid-polariton states act as an efficient and ultrafast energy-transfer pathway between the two exciton states. We argue that this type of structure may act as a model system to study energy-transfer processes in biological light-harvesting complexes. PMID:24793357

Coles, David M; Somaschi, Niccolo; Michetti, Paolo; Clark, Caspar; Lagoudakis, Pavlos G; Savvidis, Pavlos G; Lidzey, David G

2014-07-01

185

Photophysical characterization of pyrromethene 597 laser dye in silicon-containing organic matrices  

NASA Astrophysics Data System (ADS)

Samples of dipyrromethene-BF2 dye PM597 incorporated in copolymers of 3-(trimethoxysilyl)propyl methacrylate (TMSPMA) with methyl methacrylate (MMA) and 2-hydroxyethylmethacrylate (HEMA), and in terpolymers of MMA, HEMA and TMSPMA are characterized. The absorption cross-section spectra, stimulated emission cross-section spectra, and the excited-state absorption cross-section at 527 nm are determined. The fluorescence quantum distributions and fluorescence lifetimes are measured. The photo-degradation is studied under cw laser excitation conditions and quantum yields of photo-degradation are extracted. PM597 solid state samples are compared with PM597 in liquid ethyl acetate solution. The fluorescence quantum yield of PM597 is higher in doped samples (around 70%) compared to PM597 in ethyl acetate (43%). The excited-state absorption cross-section was found to be negligibly small. The photo-stability is considerably larger in the polymeric samples compared to the liquid solutions.

Susdorf, T.; Del Agua, D.; Tyagi, A.; Penzkofer, A.; García, O.; Sastre, R.; Costela, A.; García-Moreno, I.

2007-02-01

186

Nonlinear optical organic co-crystals of merocyanine dyes and phenolic derivatives with short hydrogen bonds  

NASA Astrophysics Data System (ADS)

We investigated the co-crystallization of merocyanine dyes M ( M: R-N +C 5H 4-CH?CH-C 6H 4O -, M1: R=CH 3, M2: R=HO-CH 2-CH 2-) with phenolic and aniline derivatives and show that the short or very short hydrogen bond between the two phenolic oxygen atoms which lead to a self-assembly of the M dyes and phenol derivatives is the key steering force for the co-crystallization process. The co-crystal formation was studied by melting point determination, by second-harmonic generation using the Kurtz and Perry powder test, and X-ray structural analysis. We present detailed results on the growth, polymorphism, and nonlinear optical properties of co-crystals of derivatives of M1 ( M2) and m-nitrophenol (mNP) and co-crystals of M2 and methyl 2,4-dihydroxybenzoate (MDB). Three phases of the co-crystal M2·mNP and three phases of the co-crystal M2·MDB were found. Both M2·MDB(I) and (II) have the same crystal structure (space group symmetry Cc determined by X-ray diffraction), but show different linear and nonlinear optical properties. This unusual property in the co-crystals of M2·MDB(I) and (II) may be caused by a different proton location of the short hydrogen bond (O-H-O) in the aggregation between M2 and MDB which could not be resolved by X-ray diffraction.

Bosshard, Christian; Pan, Feng; Wong, Man Shing; Manetta, Sabine; Spreiter, Rolf; Cai, Chengzhi; Günter, Peter; Gramlich, Volker

1999-07-01

187

Electrochemical oxidation of bio-refractory dye in a simulated textile industry effluent using DSA electrodes in a filter-press type FM01LC reactor  

Microsoft Academic Search

This work presents a study on degradation of indigo carmine dye in a filter-press type FM01-LC reactor using Sb2O5-doped Ti\\/IrO2-SnO2 dimensionally stable anode (DSA) electrodes. Micro- and macroelectrolysis studies were carried out using solutions of 0.8 mM indigo carmine in 0.05 M NaCl, which resemble blue denim laundry industrial wastewater. Microelectrolysis results show the behaviour of DSA electrodes in comparison with the

Francisca A. Rodríguez; María N. Mateo; Juan M. Aceves; Eligio P. Rivero; Ignacio González

2012-01-01

188

Microdochectomy Assisted by Ultrasound-Guided Indigo Carmine Staining of Intraductal Lesions: A Case Report  

PubMed Central

Spontaneous bloody nipple discharge from a single duct is a significant clinical problem. When performing preoperative marking of the discharging duct, it is sometimes difficult to identify the duct owing to intermittent discharge. Precise preoperative marking of the discharging duct and intraductal lesions is very important to avoid unnecessary wide excision of breast tissue or failure to remove the cause of nipple discharge. We herein present a case of preoperative ultrasound-guided indigo carmine staining in a patient with no discharge on the day of surgery. When a dilated duct is visualized on ultrasound, the targeted duct can be localized using indigo carmine staining, and it is possible to perform a precise minimal volume microdochectomy.

Jeong, Bo Young; Kwak, Beom Seok

2014-01-01

189

Passive mode locking of a Nd:YAG laser with a thin gelatine-film saturable absorber containing organic-dye J-aggregates  

SciTech Connect

Ultrashort pulses of duration {approx}13 ps are first obtained in a passively mode-locked Nd:YAG laser with a negative feedback using a thin gelatine-film saturable absorber containing organic-dye J-aggregates. (control of laser radiation parameters)

Avdeeva, V I; Shapiro, Boris I [Scientific Centre 'NIIKHIMFOTOPROEKT', Leningradskii prosp. 47, 125167 Moscow (Russian Federation); Kuch'yanov, Aleksandr S; Plekhanov, A I [Institute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Solominskii, Yu L; Tolmachev, Alexei I [Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Kiev (Ukraine)

2003-06-30

190

Metal-organic framework derived hierarchical ZnO parallelepipeds as an efficient scattering layer in dye-sensitized solar cells.  

PubMed

Metal-organic frameworks (MOFs) have been used in the area of photovoltaic devices via a novel approach proposed here for the first time. Hierarchical ZnO parallelepipeds were prepared from a MOF precursor, which could then act as an effective light scattering layer in dye-sensitized solar cells, leading to significantly improved cell performance. PMID:25026411

Li, Yafeng; Che, Zongzhou; Sun, Xun; Dou, Jie; Wei, Mingdeng

2014-07-29

191

Enhanced photocatalytic activity of TiO 2 nanofibers and their flexible composite films: Decomposition of organic dyes and efficient H 2 generation from ethanol-water mixtures  

Microsoft Academic Search

TiO2 nanofibers decorated with Pt and Pd nanoparticles have been synthesized and studied in various photocatalytic processes.\\u000a Excellent photocatalytic behavior in the decomposition of organic dyes in water, degradation of organic stains on the surface\\u000a of flexible freestanding cellulose\\/catalyst composite films and in generation of hydrogen from ethanol using both suspended\\u000a and immobilized catalysts are demonstrated. The performance of the

Ming-Chung Wu; András Sápi; Anna Avila; Mária Szabó; Jussi Hiltunen; Mika Huuhtanen; Géza Tóth; Ákos Kukovecz; Zoltán Kónya; Riitta Keiski; Wei-Fang Su; Heli Jantunen; Krisztián Kordás

2011-01-01

192

Effects of surface modification on dye-sensitized solar cell based on an organic dye with naphtho[2,1-b:3,4-b']dithiophene as the conjugated linker.  

PubMed

We have investigated the effects of surface modification on the dye-sensitized solar cell (DSSC) based on a donor-(?-spacer)-acceptor organic dye. A major challenge for donor-(?-spacer)--acceptor molecules as sensitizers in DSSCs is the fast recombination reactions that occur at both the photoanode (e.g., TiO2) surface and the fluorine-doped tin oxide (FTO) electrode, which presents unfavorable effects on the DSSC performance. The two interfaces of TiO2/electrolyte and FTO/electrolyte are passivated selectively in a DSSC using an organic dye with Naphtho[2,1-b:3,4-b']dithiophene as the conjugated linker and the I(-)/I3(-) electrolyte. The current density-voltage characteristics, the dark current analysis, the open circuit voltage-light intensity dependence, and the transient photovoltage/photocurrent results indicate that the recombination processes are affected strongly by surface passivation under variable light intensity. At high light intensity, the recombination reaction at the TiO2 surface is dominant. In this case, silane passivation of the TiO2 surface can suppress recombination significantly, while the c-TiO2 layer makes little contribution to the reduction of the recombination. At low illumination intensity, the recombination at FTO becomes significant, and the recombination can be reduced by applying a c-TiO2 layer. PMID:24377275

Wang, Xiaoxu; Guo, Lei; Xia, Ping Fang; Zheng, Fan; Wong, Man Shing; Zhu, Zhengtao

2014-02-12

193

Relationship between Temperature-Induced Changes in Internal Microscopic Structures of Poly(N-isopropylacrylamide) Microgels and Organic Dye Uptake Behavior.  

PubMed

Temperature-induced changes in the internal structures of poly(N-isopropylacrylamide) (pNIPAm) microgels were evaluated by small-angle X-ray scattering (SAXS), and the results were used to explain organic dye uptake by the microgels. The dye uptake experiments were conducted using two organic dyes: cationic rhodamine 6G (R6G) and anionic erythrosine. In the SAXS investigation, the internal structures of the microgels were characterized in terms of the correlation length, ?, and the distance, d*, which originated from the local packing of the isopropyl groups of two neighboring chains. With increasing temperature up to the volume phase transition temperature (VPTT) of the microgels, the correlation length, ?, was increased and the distance, d*, was decreased. At the same time, the amounts of the dyes taken up by the pNIPAm microgels were increased, despite a decrease in the volume of the microgels. The results indicated that the pNIPAm chains were closer to each other due to the hydrophobic association of isopropyl groups, which resulted in the growth of the hydrophobic domains. Thus, the hydrophobic interactions between the dyes and pNIPAm were probably accompanied by the domain formation. With a further increase of temperature above the VPTT, the correlation length, ?, was decreased and then not defined because the Ornstein-Zernike type contribution disappeared, and the distance, d*, was not largely changed. At the same time, the uptake amounts of the dyes per unit volume of the microgels were also not largely changed, which behaved similar to the distance, d*. It was probably due to the fact that the internal structures of the microgels were not largely changed because the isopropyl groups were in contact with each other. The view was supported by the result of the uptake study of the nonthermoresponsive microgels which did not have the hydrophobic isopropyl groups. PMID:25003512

Kureha, Takuma; Sato, Takaaki; Suzuki, Daisuke

2014-07-29

194

Organic sensitizers featuring a planar indeno[1,2-b]-thiophene for efficient dye-sensitized solar cells.  

PubMed

An efficient organic sensitizer (JK-306) featuring a planar indeno[1,2-b]thiophene as the ?-linker of a bridging unit for dye-sensitized solar cells (DSSCs) was synthesized. The sensitizer had a strong molar absorption coefficient and a red-shifted absorption band compared with JK-305, which resulted in a significant increase in the short-circuit photocurrent density. We incorporated a highly congested bulky amino group into the 2',4'-dihexyloxybiphenyl-4-yl moiety, an electron donor, to diminish the charge recombination and to prevent aggregation of the sensitizer. Under standard AM 1.5G solar conditions, JK-306-sensitized cells in the presence of co-adsorbents chenodeoxycholic acid (CDCA) and 4-[bis(9,9-dimethyl-9H-fluoren-2-yl)amino]benzoic acid (HC-A), which afforded an overall conversion efficiency of 8.37% and 8.52%, respectively. Upon changing the I(-) /I3 (-) electrolyte to the Co(II) /Co(III) redox couple, the cell gave rise to a significantly improved conversion efficiency of 10.02% with the multifunctional HC-A, which is one of the highest values reported for DSSCs with a cobalt-based electrolyte. Furthermore, the JK-306-based solar cell with a polymer gel electrolyte revealed a high conversion efficiency of 7.61%, which is one of the highest values for cells based on organic sensitizers. PMID:23788486

Lim, Kimin; Ju, Myung Jong; Song, Juman; Choi, In Taek; Do, Kwangsuk; Choi, Hyeju; Song, Kihyung; Kim, Hwan Kyu; Ko, Jaejung

2013-08-01

195

Detection of volatile organic compounds through a sensing film of TiO II doped with organic dyes deposited on an optical fiber  

NASA Astrophysics Data System (ADS)

The necessity of detection and recognition of different types of gases, such as volatile organic compounds, which are frequently found in food and beverage industries among others, requires the development of different types of sensors. In this work, an application of optical fiber for the detection of volatile organic compounds, particularly ethanol is presented. The sensor was constructed removing a portion of the cladding and depositing instead a sensing titanium dioxide (TiO II) film doped with an organic dye (rhodamine 6G) by the sol-gel method. The sensor response was measured in a Teflon chamber where the sample to be measured was injected. A He-Ne laser beam was coupled to the fiber and the variation in the output power was measured which indicates the gas presence. The difference between the output power with and without gas gives a measure of the concentration that exists in the chamber. The experimental results showed that for an ethanol concentration range from 0 to 10500 ppm, the response of the sensor was approximately linear with a correlation coefficient of 0.9924.

Muñoz A., S.; Ramos M., J.; Martínez H., C.; Castillo M., J.; Beltrán P., G.; Palomino M., R.

2007-06-01

196

Visible light-driven novel nanocomposite (BiVO4/CuCr2O4) for efficient degradation of organic dye.  

PubMed

In the present study, BiVO4/CuCr2O4 nanocomposites synthesized via a chemical route are applied as a photocatalyst for the degradation of methylene blue (MB) dye. The photocatalytic activity results indicated a substantial degradation of MB dye by ~90% over the surface of nanocomposite catalyst under visible light illumination. The nanocomposite showed a photocatalytic activity for MB dye degradation which is three times higher compared to that of BiVO4. This has been attributed to photogenerated electron-hole pair charge separation. The prepared photocatalysts were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis absorption and photoluminescence spectroscopy. Furthermore, an oxidizing reagent such as H2O2 was added to the photocatalytic system, which may act as an alternative electron scavenger and resulting in a notably enhanced rate of pollutant destruction. In addition, the effect of polyaniline has also been studied by synthesizing an organic/inorganic hybrid material (BiVO4/CuCr2O4/PANI). It has been observed that 95% photodegradation of organic dye takes place on the nanocomposite surface with visible light. A possible mechanism explaining the origin of enhanced performance of nanocomposite and nanohybrid is proposed. PMID:23385890

Bajaj, Rohit; Sharma, Madhulika; Bahadur, D

2013-05-21

197

Straightforward fabrication of stable white LEDs by embedding of inorganic UV-LEDs into bulk polymerized polymethyl-methacrylate doped with organic dyes  

NASA Astrophysics Data System (ADS)

Stable white-emitting down-converted LEDs are straightforwardly prepared by bulk polymerization of an organic dye doped polymethyl-methacrylate (PMMA) shell directly on top of a highly efficient commercial blue-emitting InGaN LED. Our optimized polymerization procedure allows for extending the form factor of achievable luminescence converter (LUCO) material beyond the conventional thin film form and to directly produce devices with light bulb design. The selected organic dyes, the blue-emitting Coumarin 30 and a red-emitting diketopyrrolopyrrole derivative, exhibit high compatibility with the free radical polymerization reaction of the PMMA matrix and ensure high stability of the final hybrid device. The control of both the thickness of the PMMA shell and the concentration of the dopant dyes allow for fine tuning of the emission color of the LUCO LED and to obtain white light with CIE chromatic coordinates x = 0.32 and y = 0.33, with rendering index as high as 80. This simple and versatile procedure is not dye-exclusive and is therefore extendable to other molecular systems for color-tunable efficient solid-state lighting sources.

di Martino, Daniela; Beverina, Luca; Sassi, Mauro; Brovelli, Sergio; Tubino, Riccardo; Meinardi, Francesco

2014-03-01

198

Removal of natural organic dyes from wool–implications for ancient textile provenance studies  

Microsoft Academic Search

Ancient wool textiles recovered from archaeological sites are in many cases originally dyed with natural organic dyestuffs from vegetable sources. These include among others woad (Isatis tinctoria L.), weld (Reseda luteola L.), and madder (Rubia tinctorum L.). These dyestuffs could be a threat to the use of the strontium isotopic system as a tracer for provenance studies of ancient wool,

Karin Margarita Frei; Ina Vanden Berghe; Robert Frei; Ulla Mannering; Henriette Lyngstrøm

2010-01-01

199

Favorite Demonstration: Demonstrating Indigo Carmine Oxidation-Reduction Reactions--A Choreography for Chemical Reactions  

NSDL National Science Digital Library

The indigo carmine demonstration (Ferguson et al. 1973), also referred to as a traffic-light demonstration (Flinn Scientific 2007a), is an example of a set of oxidation-reduction reactions that occurs within one solution. This type of demonstration can be used to introduce the concept of chemical reaction to undergraduate nonscience majors. Through their observations guided by the instructor, students begin to develop and construct the following concepts: color changes, reaction rates, reversible reactions, energy requirements (endothermic/exothermic), and equilibrium.

Majerich, David M.; Schmuckler, Joseph S.

2008-03-01

200

First record of the carmine spider mite, Tetranychus urticae, infesting Withania somnifera in India.  

PubMed

During April-June 2010, red two-spotted carmine spider mites Tetranychus urticae Koch (Trombidiformes: Tetranychidae) were found on aerial apical parts of Ashwagandha Withania somnifera (L.) Dunal (Solanales: Solanaceae) plants in the Amritsar District of Punjab Province in the North Indian plains. The mites fed on the leaves, making them shiny white in color, which gradually dried off and were later shed. The pest was identified as T. urticae. To best of our knowledge, this is the first record of this pest infesting W. somnifera in India. PMID:22970740

Sharma, Ashutosh; Kumar Pati, Pratap

2012-01-01

201

First Record of the Carmine Spider Mite, Tetranychus urticae, Infesting Withania somnifera in India  

PubMed Central

During April–June 2010, red two—spotted carmine spider mites Tetranychus urticae Koch (Trombidiformes: Tetranychidae) were found on aerial apical parts of Ashwagandha Withania somnifera (L.) Dunal (Solanales: Solanaceae) plants in the Amritsar District of Punjab Province in the North Indian plains. The mites fed on the leaves, making them shiny white in color, which gradually dried off and were later shed. The pest was identified as T. urticae. To best of our knowledge, this is the first record of this pest infesting W. somnifera in India.

Sharma, Ashutosh; Kumar Pati, Pratap

2012-01-01

202

Highly efficient Mo2C nanotubes as a counter electrode catalyst for organic redox shuttles in dye-sensitized solar cells.  

PubMed

Molybdenum carbide nanotubes (Mo2C-NTs) were synthesized and showed remarkable catalytic activity for regeneration of an organic sulfide redox shuttle. The dye-sensitized solar cells (DSCs) using Mo2C-NTs as the counter electrode (CE) showed a high power conversion efficiency of 6.22%, which is much higher than the DSCs using a conventional Pt CE (3.91%). PMID:24895688

Wu, Mingxing; Lin, Ya-Nan; Guo, Hongyue; Wu, Kezhong; Lin, Xiao

2014-06-19

203

Removal of Dissolved Organic Carbon and Color from Dyeing Wastewater by Pre-Ozonation and Subsequent Biological Treatment Using Test-Scale Plant  

Microsoft Academic Search

The effects of pre-ozonation and subsequent biological treatment process on the decrease in dissolved organic carbon (DOC) and color were investigated in a test-scale plant of 5 m\\/d capacity using actual raw wastewater (RW) from a dye works. Ozone dosage rate and contacting time were around 70 mg\\/L on average and 30 min, respectively. The DOC concentration was gradually decreased

Nobuyuki Takahashi; Tomoya Kumagai; Masami Shimizu; Takahisa Suzuki; Toshi Ohtsuki

2007-01-01

204

Optical dephasing of organic dye molecules doped in cross-linked polyvinyl alcohol derivatives: Incoherent photon echo and hole-burning studies  

Microsoft Academic Search

Optical dephasing of the zero-phonon line (ZPL) of organic dye molecules doped in polyvinyl alcohol (PVA) and several cross-linked PVA derivatives was studied by using the incoherent photon echoes and the photophysical persistent hole-burning. It was found in the incoherent photon echo measurements that optical dephasing time of the ZPL increases with increasing the length of a cross-linker introduced to

Shunsuke Nakanishi; Yuuichi Miyawaki; Mitsuo Nishikawa; Masayuki Amano; Seiji Fujiwara; Mayumi Jitou; Hiroshi Itoh; Masaya Kawase

1994-01-01

205

Sampling and identification of natural dyes in historical maps and drawings by liquid chromatography with diode-array detection  

Microsoft Academic Search

A simple and rapid liquid chromatographic with diode-array UV–vis spectrophotometric detection (HPLC–DAD) method for identification of natural dyes has been developed. Chromatographic retention of carminic acid, indigotin, crocetin, gambogic acid, alizarin and purpurin has been studied. The mobile phase consisted of 40mM SDS–10mM phosphate buffer solution (pH 2.3)–0.1% TFA (eluent A) and acetonitrile (eluent B) using a programmed gradient (5%

Rosario Blanc; Teresa Espejo; Ana López-Montes; David Torres; Guillermo Crovetto; Alberto Navalón; José Luis Vílchez

2006-01-01

206

Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes  

Microsoft Academic Search

This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed

Brian Yuliarto; Fahiem Fanani; M. Kasyful Fuadi; Nugraha

2010-01-01

207

Absorption cross sections, saturated vapor pressures, sublimation energies, and evaporation energies of some organic laser dye vapors  

NASA Astrophysics Data System (ADS)

A new technique of transmission measurement of overheated dye vapors is applied to determine absolute absorption cross-section spectra of three active dyes for vapor phase dye lasers. The investigated compounds are 1,4-di/2-(5-phenyloxazolyl)/-benzene (POPOP), 1,4-di/2-(4-methyl-5-phenyl-oxazolyl)/-benzene (dimethyl-POPOP), and 2,5-diphenylfuran (PPF). The vapor absorption spectra are compared with liquid solution spectra in order to obtain information on the dye-solvent interaction. The saturated vapor densities are determined by transmission measurements after knowing the absolute absorption cross-section spectra. The latent heats of sublimation, evaporation, and melting are derived by analyzing the dependences of the saturated vapor densities on the vapor temperature.

Schmidt, J.; Penzkofer, A.

1989-08-01

208

Molecular organization and aggregation in Langmuir and Langmuir-Blodgett films of azo dye/liquid crystal mixtures  

NASA Astrophysics Data System (ADS)

A study of azo dye/liquid crystal mixtures in monolayers formed at air-water (Langmuir films) and air-solid substrate (Langmuir-Blodgett films) interfaces was performed. Three azo dyes with various molecular structure and two liquid crystal materials: 4-octyl-4'-cyanobiphenyl (8CB) and trans-4-octyl(4'-cyanophenyl)-cyclohexane (8PCH) were used. The morphology of Langmuir films was monitored by means of a Brewster angle microscope (BAM). Moreover, a surface pressure and electronic absorption spectra of the monolayer spread on the water surface of dye/liquid crystal mixtures as a function of a mean molecular area were simultaneously recorded. In addition, the absorption for Langmuir-Blodgett films deposited on quartz plates was measured. Information about intermolecular interactions in the mixtures of the nonamphiphilic dye and the liquid crystal with polar terminal group was obtained. Conclusions about the formation of self-aggregates between dye molecules have been drawn. The influence of the dye molecular structure and its concentration on aggregates’ geometry was found.

Inglot, K.; Marty?ski, T.; Bauman, D.

2009-06-01

209

Organic additives assisted synthesis of mesoporous ?-Ga2O3 nanostructures for photocatalytic dye degradation  

NASA Astrophysics Data System (ADS)

Functional semiconductor ?-Ga2O3 nanostructures with interesting morphologies like blocks, spindles and rods were fabricated using hydrothermal process employing cationic (CTAB), anionic (SDS) and non-ionic (PEG) organic additives. Well-defined and monodispersed uniform mesoporous nanostructures of ?-Ga2O3 were observed using scanning electron microscopy. The diameter of nanostructures was evaluated from transmission electron microscopy images and was found to be ˜125, 70 and 50 nm, respectively, for nanoblocks, nanospindles and nanorods, which are in accordance with XRD analysis. Structural characterization using XRD and FTIR spectroscopy revealed the single crystalline monoclinic structure of ?-Ga2O3 with high purity. The thermal decomposition process was monitored through a thermogravimetric/differential thermal analyzer. The N2 adsorption/desorption analysis revealed the distribution of mesopores with high surface area. Furthermore, the photocatalytic activities of semiconductor ?-Ga2O3 nanostructures toward Rhodamine B under ultraviolet light showed enhanced activity over commercial Degussa P25 and bulk Ga2O3, with ?-Ga2O3 nanorods presenting higher photocatalytic ability. The enhanced photocatalytic activity of ?-Ga2O3 nanostructures ascribed to specific surface area, pore size distribution and optical properties have also been addressed.

Girija, K.; Thirumalairajan, S.; Patra, Astam K.; Mangalaraj, D.; Ponpandian, N.; Viswanathan, C.

2013-03-01

210

Investigation of dye-doped red emitting organic electroluminescent devices with metal-mirror microcavity structure  

NASA Astrophysics Data System (ADS)

Organic electroluminescent (EL) devices with planar microcavity structure, indium-tin-oxide/Ag/N,N'-diphenyl-N , N '-bis(3-methylphenyl)-1,1'-biphenyl-4 , 4'-diamine/tris(8-hydroxyquinoline)-aluminum (AlQ):4-(dicyanomethylene)-2-methyl-6-(p-dimethyl aminostyryl)-4H-pyran/AlQ/LiF/Al, were fabricated. The Ag and Al layers acted as not only hole-injection layer and cathode, respectively, but reflective mirrors, resulting in strong microcavity effects, such as spectral narrowing and directional emission. The effects of device parameters on the EL performance were studied in detail and were discussed in terms of conventional microcavity theory. On-axis light magnification with a coefficient (EL enhancement ratio between cavity and noncavity devices) of ~5 was observed, which was consistent with the theoretical calculation. At the same time, optimized microcavity device with bright pure red emission showed maximum luminance of 5140 cd/m2, peak at 624 nm, Commission International de I'Eclairage coordinates of x=0.663 and y=0.336, and high EL efficiency of 1.71 cd/A were obtained.

Sun, X. Y.; Li, W. L.; Hong, Z. R.; Wei, H. Z.; Zang, F. X.; Chen, L. L.; Shi, Z.; Bi, D. F.; Li, B.; Zhang, Z. Q.; Hu, Z. Z.

2005-05-01

211

High molar extinction coefficient organic sensitizers for efficient dye-sensitized solar cells.  

PubMed

We have designed and synthesized highly efficient organic sensitizers with a planar thienothiophene-vinylene-thienothiophene linker. Under standard global AM 1.5 solar conditions, the JK-113-sensitized cell gave a short circuit photocurrent density (J(sc)) of 17.61 mA cm(-2), an open-circuit voltage (V(oc)) of 0.71 V, and a fill factor (FF) of 72%, corresponding to an overall conversion efficiency (eta) of 9.1%. The incident monochromatic photo-to-current conversion efficiency (IPCE) of JK-113 exceeds 80% over the spectral region from 400 to 640 nm, reaching its maximum of 93% at 475 nm. The band tails off toward 770 nm, contributing to the broad spectral light harvesting. Solar-cell devices based on the sensitizer JK-113 in conjunction with a volatile electrolyte and a solvent-free ionic liquid electrolyte gave high conversion efficiencies of 9.1% and 7.9%, respectively. The JK-113-based solar cell fabricated using a solvent-free ionic liquid electrolyte showed excellent stability under light soaking at 60 degrees C for 1000 h. PMID:19998435

Choi, Hyunbong; Raabe, Ines; Kim, Duckhyun; Teocoli, Francesca; Kim, Chulwoo; Song, Kihyung; Yum, Jun-Ho; Ko, Jaejung; Nazeeruddin, Md K; Grätzel, Michael

2010-01-25

212

Degradation of Dye Wastewater by ns-Pulse DBD Plasma  

NASA Astrophysics Data System (ADS)

Two plasma reactors have been developed and used to degrade dye wastewater agents. The configuration of one plasma reactor is a comb-like extendable unit module consisting of 5 electrodes covered with a quartz tube and the other one is an array reactor which is extended from the unit module. The decomposition of wastewater by ns pulse dielectric barrier discharge (DBD) plasma have been carried out by atomizing the dyeing solutions into the reactors. During experiments, the indigo carmine has been treated as the waste agent. The measurements of UV-VIS absorption spectroscopy and the chemical oxygen demand (COD) are carried out to demonstrate the decomposition effect on the wastewater. It shows that the decoloration rate of 99% and the COD degradation rate of 65% are achieved with 15 min treatment in the unit reactor. The effect of electrical parameters on degradation has been studied in detail. Results from the array reactor indicate that it has a better degradation effect than the unit one. It can not only totally remove the chromogenic bond of the indigo carmine solution, but also effectively degrade unsaturated bonds. The decoloration rate reaches 99% after 10 min treatment, the decomposition rate of the unsaturated bond reaches 83% after 60 min treatment, and the COD degradation rate is nearly 74%.

Gao, Jin; Gu, Pingdao; Yuan, Li; Zhong, Fangchuan

2013-09-01

213

76 FR 3584 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...  

Federal Register 2010, 2011, 2012, 2013

...Docket No. TTB-2010-0008; Notice No. 111] RIN 1513-AB79 Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages Correction In proposed rule document 2010-27733 beginning on page 67669 in the...

2011-01-20

214

Hair Dyes  

Microsoft Academic Search

\\u000a Contact dermatitis to hair dye ingredients have been known since human started dyeing with aromatic amines like p-phenylenediamine\\u000a (PPD). Hair dye allergy may cause severe clinical reactions, with edema of the face, eyelids, and scalp. More moderate reactions\\u000a such as erythema, suppuration, and ulceration, typically at the scalp margin, on the ears, and sometimes with evidence of\\u000a eczema where the

David Basketter; Jeanne Duus Johansen; John McFadden; Heidi Søsted

215

Electrodeposition of nanoporous ZnO on Al-doped ZnO leading to a highly organized structure for integration in Dye Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

In the present study, we propose an improvement of the anode configuration in Zinc Oxide based Dye Sensitized Solar Cells (DSSC). Instead of the classical configuration, which is composed by two different metal oxides: one transparent conducting oxide (TCO) for the substrate and one nanostructured metal oxide for supporting the dye, the new approach is to use ZnO as unique material. Thus, nanoporous zinc oxide films have been electrodeposited on a sputtered Al doped ZnO layers with varying thicknesses up to 6 ?m. The evolution of the porosity of the structure has been studied by scanning electron microscope (SEM) and electrochemical impedance spectroscopy and compared with standard nanoporous ZnO grown on fluorine doped tin oxide (SnO2:F noted FTO). This results firstly in the modification of the nanoporous structure morphology and secondly a better adhesion between the nanoporous layer and the substrate. Organization in the nanoporous material is enhanced with regular pores arrays and perpendicular to the substrate. Dye sensitized solar cells based on this simplified architecture present efficiencies up to 4.2% and 4.5% with N719 and D149 respectively as sensitizers. Higher fill factor and Voc are found in comparison with the one obtained for deposition on the classical transparent conducting oxide (FTO), which denote improved electrical transfer properties.

Haller, S.; Rousset, J.; Renou, G.; Lincot, D.

2011-10-01

216

Functionalization of self-organized TiO2 nanotubes with Pd nanoparticles for photocatalytic decomposition of dyes under solar light illumination.  

PubMed

Self-organized, vertically oriented TiO2 nanotube arrays prepared by the sonoelectrochemical anodization method are functionalized with palladium (Pd) nanoparticles of approximately 10 nm size. A simple incipient wetness method is adopted to distribute the Pd nanoparticles uniformly throughout the TiO2 nanotubular surface. This functionalized material is found to be an excellent heterogeneous photocatalyst that can decompose nonbiodegradable azo dyes (e.g., methyl red and methyl orange) rapidly (150-270 min) and efficiently (100%) under ambient conditions using simulated solar light in the absence of any external oxidative radicals such as hydrogen peroxide. PMID:18729485

Mohapatra, Susanta K; Kondamudi, Narasimharao; Banerjee, Subarna; Misra, Mano

2008-10-01

217

Simultaneous identification of natural dyes in the collection of drawings and maps from The Royal Chancellery Archives in Granada (Spain) by CE  

Microsoft Academic Search

A simple and rapid capillary electrophoretic method with UV detection (CE-UV) has been developed for the identification of five natural dyes namely, carmine, indigo, saffron, gam- boge and Rubia tinctoria root. The separation was performed in a fused-silica capillary of 64.5 cm length and 50 mm id. The running buffer was 40 mM sodium tetraborate buffer solution (pH 9.25). The

Ana López-Montes; Rosario Blanc García; Teresa Espejo; José F. Huertas-Perez; Alberto Navalón; José Luis Vílchez

2007-01-01

218

Dye lasers  

SciTech Connect

This patent describes a dye laser. It consists of a composite composition of an inorganic oxide glass monolith with a microporous structure containing an incorporated solution comprising a solvent component and a lasable dye component. Wherein the glass monolith has sealed outer surfaces.

Kuder, J.E.; McGinnis, J.L.; Goldberg, H.A.; Hart, T.R.; Che, T.M.

1989-10-31

219

Enhancing the color gamut of white displays using novel deep-blue organic fluorescent dyes to form color-changed thin films with improved efficiency  

NASA Astrophysics Data System (ADS)

This study used novel fluorescence based deep-blue-emitting molecules, namely BPVPDA, an organic fluorescence color thin film using BPVPDA exhibit deep blue fluorine with CIE coordinates of (0.13,0.16). The developed original Organic RGB color thin film technology enables the optimization of the distinctive features of an organic light emitting diode (OLED) and (TFT) LCD display. The color filter structure maintains the same high resolution to obtain a higher level of brightness, in comparison with conventional organic RGB color thin film. The image-processing engine is designed to achieve a sharp text image for a thin-film-transistor (TFT) LCD with organic color thin films. The organic color thin films structure uses organic dye dopent in limpid photo resist. With this technology , the following characteristics can be obtained: (1) high color reproduction of gamut ratio, and (2) improved luminous efficiency with organic color fluorescence thin film. This performance is among the best results ever reported for a color-filter used on TFT-LCD and OLED.

Liu, Wei-ting; Huang, Wen-Yao

2012-05-01

220

Enhancing the color gamut of white displays using novel deep-blue organic fluorescent dyes to form color-changed thin films with improved efficiency  

NASA Astrophysics Data System (ADS)

This study used the novel fluorescence based deep-blue-emitting molecule BPVPDA in an organic fluorescent color thin film to exhibit deep blue color with CIE coordinates of (0.13, 0.16). The developed original organic RGB color thin film technology enables the optimization of the distinctive features of an organic light emitting diode (OLED) and thin-film-transistor (TFT) LCD display. The color filter structure maintains the same high resolution to obtain a higher level of brightness in comparison with conventional organic RGB color thin film. The image-processing engine is designed to achieve a sharp text image for a TFT LCD with organic color thin films. The organic color thin films structure uses an organic dye dopant in a limpid photoresist. With this technology, the following characteristics can be obtained: 1. high color reproduction of gamut ratio, and 2. improved luminous efficiency with organic color fluorescent thin film. This performance is among the best results ever reported for a color-filter used on TFT-LCD or OLED.

Liu, Wei-Ting; Huang, Wen-Yao

2012-10-01

221

Electron transfer properties of organic dye-sensitized solar cells based on indoline sensitizers with ZnO nanoparticles.  

PubMed

Two indoline dyes, coded D149 and D205, were used as the sensitizers of ZnO dye-sensitized solar cells (DSCs) with optimal energy conversion efficiencies of more than 5%, under AM 1.5 full sunlight illumination (100 mW cm( - 2)). Higher interfacial charge transfer rate and retardant fluorescence decay confirmed from transient fluorescence illustrated that D205-sensitized ZnO DSCs could possess better electron transport than D149-sensitized ZnO DSCs. The enhancement of V(oc) and J(sc) for D205-sensitized ZnO DSCs was ascribed to the effective suppression of electron recombination by extending the alkyl chain on the terminal rhodanine moiety from ethyl to octyl. The evidence of enhanced electron diffusion coefficient was further shown by electrochemical impedance spectroscopy (EIS). PMID:21051799

Cheng, Hsin-Ming; Hsieh, Wen-Feng

2010-12-01

222

Laser dye toxicity, hazards, and recommended controls  

SciTech Connect

Laser dyes are complex fluorescent organic compounds which, when in solution with organic solvents, form a lasing medium. The wavelength of a dye laser's output beam can vary with different dyes, concentrations, and solvents, giving it a tunable feature capable of emitting ultraviolet, visible, or infrared radiation. Toxicity information on the approximately 100 commercially available laser dyes is very scarce. Limited animal experimentation has been performed with only a few dyes. This paper summarizes what is known about laser dye toxicity, and offers recommendations for controlling dye hazards. The laser dyes investigated have been categorized according to their central chemical structures. These include the xanthenes (rhodamines and fluoresceins), polymethines (cyanines and carbocyanines), coumarins, and stilbenes. A few other miscellaneous dyes that do not fall into one of these categories have also been investigated. Prepared laser dye solutions usually contain very small quantities of dye--typical dye concentrations are 10/sup -2/ to 10/sup -5/ molar. For this reason, the solvent in which the dye is dissolved plays an important role when defining potential hazards. Practically all the solvents used are flammable and toxic by inhalation and skin absorption, and therefore must be controlled properly.

Mosovsky, J.A.

1983-05-06

223

Free amino and imino-bridged centres attached to organic chains bonded to structurally ordered silica for dye removal from aqueous solution.  

PubMed

Ordered mesoporous SBA-15 type silica was synthesized by sol gel polymerization and reacted with 3-aminopropyltriethoxysilane (AP) or triethylenetetramine (TE), to attach pendant chains or bridging molecules, with basic centres. The materials were characterized by elemental analysis, infrared spectroscopy, and nuclear magnetic resonance in the solid state, X-ray diffractometry, scanning and transmission electron microscopy. The nitrogen sorption/desorption data for SBA-15 and the organofunctionalized SBA-15AP and SBA-15TE silicas resulted in IV type isotherms with hysteresis loops of the H1 type, surface areas of 800; 213 and 457 m(2) g(-1) and average pore diameters of 8.0; 3.2 and 6.8 nm, respectively. The ordered structural features of the mesoporous silica remained preserved after post-functionalization with pendant and bridged organic chains. Sorption data for organofunctionalized silicas gave highly selective sorption capacities for anionic water soluble Reactive Blue dye, with 0.064 and 0.072 mmol g(-1). Negligible sorption was observed with the unmodified mesoporous silica. The results suggest that organofunctionalized silica can be a simple, efficient, inexpensive and suitable method for the effective and selective removal of anionic organic dye pollutants from aqueous solutions. PMID:24374243

Rehman, Fozia; Volpe, Pedro L O; Airoldi, Claudio

2014-01-15

224

Treatment of a textile effluent from dyeing with cochineal extracts using Trametes versicolor fungus.  

PubMed

Trametes versicolor (Tv) fungus can degrade synthetic dyes that contain azo groups, anthraquinone, triphenylmethane polymers, and heterocyclic groups. However, no references have been found related to the degradation of natural dyes, such as the carminic acid that is contained in the cochineal extract. Experiments to determine the decolorization of the effluent used in the cotton dyeing process with cochineal extract by means of Tv fungus were done. Treatments to determine decolorization in the presence or absence of Kirk's medium, glucose, and fungus, with an addition of 50% (v v-1) of nonsterilized effluent were performed. Physicochemical characterization was performed at the start and end of the treatment. Degradation kinetics were determined. A direct relationship was found between the dry weight of fungi, pH, and the decolorization system, with higher decolorization at lower pH levels (pH ~4.3). High decolorization (81% ± 0.09; 88% ± 0.17; and 99% ± 0.04) for three of the eight treatments (Kirk's medium without glucose, Kirk's medium with glucose, and without medium with glucose, respectively) was found. Toxicity tests determined an increase in the initial effluent toxicity (7.33 TU) compared with the final treatment (47.73 TU) in a period of 11 days. For this system, a degradation sequence of the carminic acid structure present in the effluent by the Tv fungus is suggested, in which it is seen that metabolites still containing aromatic structures are generated. PMID:21552764

Arroyo-Figueroa, Gabriela; Ruiz-Aguilar, Graciela M L; López-Martínez, Leticia; González-Sánchez, Guillermo; Cuevas-Rodríguez, Germán; Rodríguez-Vázquez, Refugio

2011-01-01

225

Study of nonlinear refraction of organic dye by Z-scan technique using He-Ne laser  

SciTech Connect

Laser induced third-order nonlinear optical responses of Brilliant Green solution has been investigated by utilizing single beam Z-scan technique with a continuous-wave He-Ne laser radiation at 632.8 nm. It was observed that the material exhibits self-defocusing type optical nonlinearity. The measurements of nonlinear refraction were carried out at different dye concentrations and found that the increase in solution concentration leads to the linear increase of the nonlinear refractive index. The experimental results confirm great potential of the Brilliant Green for the application in nonlinear optical devices.

Medhekar, S.; Kumar, R.; Mukherjee, S.; Choubey, R. K. [Dept. of Applied Physics, Birla Institute of Technology, Mesra, Ranchi - 835215, Jharkhand (India)

2013-02-05

226

Fluorescence Resonance Energy Transfer between organic dyes adsorbed onto nano-clay and Langmuir-Blodgett (LB) films  

NASA Astrophysics Data System (ADS)

In this communication we investigate two dyes N, N'-dioctadecyl thiacyanine perchlorate (NK) and octadecyl rhodamine B chloride (RhB) in Langmuir and Langmuir-Blodgett (LB) films with or with out a synthetic clay laponite. Observed changes in isotherms of RhB in absence and presence of nano-clay platelets indicate the incorporation of clay platelets onto RhB-clay hybrid films. AFM images confirm the incorporation of clay into hybrid films. FRET is observed in clay dispersion and LB films with and without clay. Efficiency of energy transfer is maximum in LB films with clay.

Hussain, Syed Arshad; Chakraborty, S.; Bhattacharjee, D.; Schoonheydt, R. A.

2010-02-01

227

Graphene nanoplatelets doped with N at its edges as metal-free cathodes for organic dye-sensitized solar cells.  

PubMed

Challenging precious Pt-based electrocatalysts for dye-sensitized solar cells (DSSCs), graphene nanoplatelets that are N-doped at the edges (NGnPs) are prepared via simply ball-milling graphite in the presence of nitrogen gas. DSSCs based on specific nanoplatelets designated "NGnP5" display superior photovoltaic performance (power conversion efficiency, 10.27%) compared to that of conventional Pt-based devices (9.96%). More importantly, the NGnP counter electrode exhibits outstanding electrochemical stability and electrocatalytic activity with a cobalt-complex redox couple. PMID:24677174

Ju, Myung Jong; Jeon, In-Yup; Kim, Jae Cheon; Lim, Kimin; Choi, Hyun-Jung; Jung, Sun-Min; Choi, In Taek; Eom, Yu Kyung; Kwon, Young Jin; Ko, Jaejung; Lee, Jae-Joon; Kim, Hwan Kyu; Baek, Jong-Beom

2014-05-21

228

Vertical-cavity surface-emitting laser in the long-wavelength (700 nm) region in the visible by energy transfer between organic dyes  

NASA Astrophysics Data System (ADS)

In this work, organic vertical-cavity surface-emitting lasers (VCSELs) with single-mode laser output in the long-wavelength region (~700 nm) of the visible were reported based on the energy transfer between dye pairs consisting of pyrromethene 597 (PM597) and rhodamine 700 (LD700). By co-doping PM597 into the polymeric hosts, the fluorescence intensity of LD700 was enhanced by 30-fold and the photophysical parameters of the donor-acceptor pairs were investigated, indicating the involvement of non-radiative resonance energy transfer processes between PM597 and LD700. Active distributed Bragg reflectors (DBR) were made by alternately spin-coating dye-doped polyvinylcarbazole and cellulose acetate thin films as the high and low refractive index layers, respectively. By sandwiching the active layer with 2 DBR mirrors, VCSEL emission at 698.9 nm in the biological first window (650-950 nm) was observed under the 532-nm laser pulses. The laser slope efficiency and threshold were also measured.

Liao, Zhifu; Zhou, Yuan; Cui, Yuanjing; Yang, Yu; Wang, Zhiyu; Qian, Guodong

2014-06-01

229

[Study on removal effect of different organic fractions from bio-treated effluent of dye wastewater by UV/H2O2 process].  

PubMed

The pretreatment of bio-treated effluent of dye wastewater by UV/H2O2 process was studied. The influencing factors, such as H2O2 dosage, reaction time and pH values were evaluated for the removal efficiency of UV254, ADMI7.6, DOC and DOC of dye wastewater by UV/H2O2 process. The experimental results showed that,the optimal conditions determined were as follows: initial pH 7.4-8.1, H2O2 dosage 4.5 mmol x L(-1) and UV irradiation time of 50 min. Under the optimal conditions, UV254, ADMI7.6, DOC and COD removal rate could reach 77%, 94%, 40% and 69%. Removal effects of four different DOM fractions, hydrophobic acids, non-acid hydrophobics, tasnsphilics and hydrophilics separated by XAD-8 and XAD-4 resins. The experimental results show that: hydrophobic material was the main substance causing color, when it was characterized by ADMI7.6, the proportion could reach 92%, of which 53% was non-acid hydrophobics. It indicated that removal efficiencies of tasnsphilics, hydrophobic acids and non-acid hydrophobics were high through UV/H2O2, process, while hydrophilics' efficiencies were lower. The experimental results showed that organic molecules with molecular weight over 10,000 contributed greatly to UV254, ADMI7.6 and DOC removal rate. PMID:23213897

Li, Xin; Liu, Yong-di; Sun, Xian-bo; Xu, Hong-yong; Qian, Fei-yue; Li, Xin-jue; Li, Mu

2012-08-01

230

Decolorization of triphenylmethane dyes and textile and dye-stuff effluent by Kurthia sp  

Microsoft Academic Search

A number of soil and water samples were collected from the vicinity of effluent treatment plant of a textile and dyeing industry. Several organisms were screened for their ability to decolorize triphenylmethane group of dyes. A Kurthia sp. was selected on the basis of rapid dye decolorizing activity. Under aerobic conditions, 98% color was removed intracellularly by this strain. A

Rajesh Kumar Sani; Uttam Chand Banerjee

1999-01-01

231

Vibrational spectroscopy to study degradation of natural dyes. Assessment of oxygen-free cassette for safe exposition of artefacts.  

PubMed

An important issue connected with conservation chemistry is how to improve the storage and exposure conditions in order to suppress the fading and degradation of dyes and other components of paintings. Although the oxygen-free exposure cassettes are commonly known in museums, there is still lack of information in the literature about the effect of anoxic conditions on the degradation of dyes. This study is an attempt to start a database formation on the dyes degradation. Five commercial dyes (indigo, dragon's blood, curcumin, madder, carminic acid) were submitted to accelerated ageing by exposure to intensive light in the visible range in both oxygen-free (anoxia) and -rich conditions. Degradation of the samples was investigated by several analytical techniques (attenuated total reflectance infrared spectroscopy, Raman spectroscopy, reflectance UV-Vis spectroscopy, X-ray fluorescence spectroscopy and optical microscopy). The conclusions are based on the estimators (derived from the determination of colour differences from Vis spectra and from the changes in FTIR and Raman vibrational bands intensity). According to them, only indigo, dragon's blood and curcumin show greater stability in anoxic conditions in comparison with oxygen-rich ones while madder, carminic acid undergo greater degradation. PMID:21165610

Koperska, Monika; ?ojewski, Tomasz; ?ojewska, Joanna

2011-03-01

232

Dispersive liquid-phase microextraction with solidification of floating organic droplet coupled with high-performance liquid chromatography for the determination of Sudan dyes in foodstuffs and water samples.  

PubMed

Dispersive liquid-phase microextraction with solidification of floating organic drop (SFO-DLPME) is one of the most interesting sample preparation techniques developed in recent years. In this paper, a new, rapid, and efficient SFO-DLPME coupled with high-performance liquid chromatography (HPLC) was established for the extraction and sensitive detection of banned Sudan dyes, namely, Sudan I, Sudan II, Sudan III, and Sudan IV, in foodstuff and water samples. Various factors, such as the type and volume of extractants and dispersants, pH and volume of sample solution, extraction time and temperature, ion strength, and humic acid concentration, were investigated and optimized to achieve optimal extraction of Sudan dyes in one single step. After optimization of extraction conditions using 1-dodecanol as an extractant and ethanol as a dispersant, the developed procedure was applied for extraction of the target Sudan dyes from 2 g of food samples and 10 mL of the spiked water samples. Under the optimized conditions, all Sudan dyes could be easily extracted by the proposed SFO-DLPME method. Limits of detection of the four Sudan dyes obtained were 0.10-0.20 ng g(-1) and 0.03 ?g L(-1) when 2 g of foodstuff samples and 10 mL of water samples were adopted, respectively. The inter- and intraday reproducibilities were below 4.8% for analysis of Sudan dyes in foodstuffs. The method was satisfactorily used for the detection of Sudan dyes, and the recoveries of the target for the spiked foodstuff and water samples ranged from 92.6 to 106.6% and from 91.1 to 108.6%, respectively. These results indicated that the proposed method is simple, rapid, sensitive, and suitable for the pre-concentration and detection of the target dyes in foodstuff samples. PMID:24894629

Chen, Bo; Huang, Yuming

2014-06-25

233

Discoloration of indigo carmine using aqueous extracts from vegetables and vegetable residues as enzyme sources.  

PubMed

Several vegetables and vegetable residues were used as sources of enzymes capable to discolor indigo carmine (IC), completely or partially. Complete discoloration was achieved with aqueous extracts of green pea seeds and peels of green pea, cucumber, and kohlrabi, as well as spring onion leaves. The source of polyphenol oxidase (PPO), pH, time, and aeration is fundamental for the discoloration process catalyzed by PPO. The PPO present in the aqueous extract of green pea seeds was able to degrade 3,000?ppm of IC at a pH of 7.6 and magnetic stirring at 1,800?rpm in about 36?h. In addition, at 1,800?rpm and a pH of 7.6, this extract discolored 300?ppm of IC in 1:40?h; in the presence of 10% NaCl, the discoloration was complete in 5:50?h, whereas it was completed in 4:30?h with 5% NaCl and 2% laundry soap. PMID:24151588

Solís, A; Perea, F; Solís, M; Manjarrez, N; Pérez, H I; Cassani, J

2013-01-01

234

Quasi solid state dye sensitized solar cells employing a polymer electrolyte and xanthene dyes  

Microsoft Academic Search

A series of organic dyes in the xanthene class namely Rose Bengal (RB), Eosin Y (EY) and Fluorescein sodium (FLU) were used as photo-sensitizer for nano-crystalline TiO2, for the application of quasi solid state dye sensitized solar cells. These dyes have same backbone with different number of electron acceptor groups. The dye with the highest number of electron acceptor group,

G. D. Sharma; P. Balraju; Manish Kumar; M. S. Roy

2009-01-01

235

Photocatalytic degradation of organic dyes by La(3+)/Ce(3+)-H3PW12O40 under different light irradiation.  

PubMed

New photocatalysts (La(3+)-H3PW12O40 and Ce(3+)-H3PW12O40) were prepared, and the degradation activity of these products was evaluated. These photocatalysts were synthesized by the hydrothermal method assisted by PEG-1000 from the reactions of LaCl3 or CeCl3 and phosphotungstic acid. The prepared catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), ultraviolet-visible diffuse reflection spectroscopy (UV-vis) and thermal gravimetric analysis (TGA). The catalytic activity of La(3+)-H3PW12O40 and Ce(3+)-H3PW12O40 was evaluated by adopting methyl orange (MO) and Rhodamine B (RhB) as model dyes, and the reaction was carried out under UV- and visible light irradiation. PMID:24805777

Li, Taohai; Li, Quanguo; Yan, Jing; Li, Feng

2014-05-28

236

water-Dispersible, pH-stable and highly-luminescent organic dye nanoparticles with amplified emissions for in vitro and in vivo bioimaging.  

PubMed

A new strategy is presented for using doped small-molecule organic nanoparticles (NPs) to achieve high-performance fluorescent probes with strong brightness, large Stokes shifts and tunable emissions for in vitro and in vivo imaging. The host organic NPs are used not only as carriers to encapsulate different doped dyes, but also as fluorescence resonance energy transfer donors to couple with the doped dyes (as acceptors) to achieve multicolor luminescence with amplified emissions (AE). The resulting optimum green emitting NPs show high brightness with quantum yield (QY) of up to 45% and AE of 12 times; and the red emitting NPs show QY of 14% and AE of 10 times. These highly-luminescent doped NPs can be further surface modified with poly(maleic anhydride-alt-1-octadecene)-polyethylene glycol (C18PMH-PEG), endowing them with excellent water dispersibility and robust stability in various bio-environments covering wide pH values from 2 to 10. In this study, cytotoxicity studies and folic acid targeted cellular imaging of these multicolor probes are carried out to demonstrate their potential for in vitro imaging. On this basis, applications of the NP probes in in vivo and ex vivo imaging are also investigated. Intense fluorescent signals of the doped NPs are distinctly, selectively and spatially resolved in tumor sites with high sensitivity, due to the preferential accumulation of the NPs in tumor sites through the passive enhanced permeability and retention effect. The results clearly indicate that these doped NPs are promising fluorescent probes for biomedical applications. PMID:24318966

Yu, Jia; Diao, Xiaojun; Zhang, Xiujuan; Chen, Xianfeng; Hao, Xiaojun; Li, Wei; Zhang, Xiaohong; Lee, Chun-Sing

2014-03-26

237

Water-Soluble Fluorescing and Laser Dyes.  

National Technical Information Service (NTIS)

This invention relates to water-soluble lasing dyes. When dyes are used in lasers, they are usually dissolved in organic solvents. One widely used solvent is ethanol. As a solvent, water offers advantages over organic compounds in that it is more readily ...

R. A. Henry

1978-01-01

238

Dyeing properties of natural dyes extracted from eucalyptus  

Microsoft Academic Search

A natural dye was extracted from Eucalyptus camaldulensis and was used to dye cotton by direct dyeing method at different dyeing conditions. Then, the fastness properties of dyeing with different dyeing techniques were compared.

S. Ali; N. Nisar; T. Hussain

2007-01-01

239

Rattle-type carbon-alumina core-shell spheres: synthesis and application for adsorption of organic dyes.  

PubMed

Porous micro- and nanostructured materials with desired morphologies and tunable pore sizes are of great interests because of their potential applications in environmental remediation. In this study, novel rattle-type carbon-alumina core-shell spheres were prepared by using glucose and metal salt as precursors via a simple one-pot hydrothermal synthesis followed by calcination. The microstructure, morphology, and chemical composition of the resulting materials were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N(2) adsorption-desorption techniques. These rattle-type spheres are composed of a porous Al(2)O(3) shell (thickness ? 80 nm) and a solid carbon core (diameter ? 200 nm) with variable space between the core and shell. Furthermore, adsorption experiments indicate that the resulting carbon-alumina particles are powerful adsorbents for the removal of Orange-II dye from water with maximum adsorption capacity of ~210 mg/g. It is envisioned that these rattle-type composite particles with high surface area and large cavities are of particular interest for adsorption of pollutants, separation, and water purification. PMID:22458371

Zhou, Jiabin; Tang, Chuan; Cheng, Bei; Yu, Jiaguo; Jaroniec, Mietek

2012-04-01

240

Optical microring resonators constructed from organic dye nanofibers and their application to miniaturized channel drop/add filters.  

PubMed

We fabricated micrometer-scale optical ring resonators by micromanipulation of thiacyanine (TC) dye nanofibers that propagate exciton polaritons (EPs) along the fiber axis. High mechanical flexibility of the nanofibers and a low bending loss property of EP propagation enabled the fabrication of microring resonators with an average radius (r(ave)) as small as 1.6 ?m. The performances of the fabricated resonators (r(ave) = 1.6-8.9 ?m) were investigated by spatially resolved microscopy techniques. The Q-factors and finesses were evaluated as Q ? 300-3500 and F ? 2-12. On the basis of the r(ave)-dependence of resonator performances, we revealed the origin of losses in the resonators. To demonstrate the applicability of the microring resonators to photonic devices, we fabricated a channel drop filter that comprises a ring resonator (r(ave) = 3.9 ?m) and an I/O bus channel nanofiber. The device exhibited high extinction ratios (4-6 dB) for its micrometer-scale dimensions. Moreover, we successfully fabricated a channel add filter comprising a ring resonator (r(ave) = 4.3 ?m) and two I/O bus channel nanofibers. Our results demonstrated a remarkable potential for the application of TC nanofibers to miniaturized photonic circuit devices. PMID:23802740

Takazawa, Ken; Inoue, Jun-ichi; Mitsuishi, Kazutaka

2013-07-10

241

Transparent bifacial dye-sensitized solar cells based on organic counter electrodes and iodine-free electrolyte  

NASA Astrophysics Data System (ADS)

In this study, a novel bifacially active transparent dye-sensitized solar cell (DSSCs) assembled with a transparent poly(3,4-ethylenedioxythiophene) (PEDOT) counter electrode and a colorless iodine-free polymer gel (IFPG) electrolyte was developed. The IFPG electrolyte was prepared by employing an ionic liquid (1,2-dimethyl-3-propylinmidazolium iodide, DMPII) as the charge transfer intermediate and a polymer composite as the gelator without the addition of iodine, exhibiting high conductivity and non-absorption characters. PEDOT electrodes were prepared via a facile electro-polymerization method. By controlling the amount of polymerization charge capacity, we optimized the PEDOT electrodes with high transparency and a favorable activity for catalyzing the IFPG electrolyte. The bifacial DSSCs device fabricated by this kind of transparent PEDOT electrode and colorless IFPG electrolyte showed a power conversion efficiency (PCE) of 6.35% and 4.98% at 100 mW cm-2 AM1.5 illumination corresponding to front- and rear-side illumination. It is notable that the PCE under rear-side illumination approaches 80% that of front-side illumination. Moreover, the device shows excellent stability as confirmed by aging test. These promising results highlight the enormous potential of this transparent PEDOT CE and colorless IFPG electrolyte in scaling up and commercialization of low cost and effective bifacial DSSCs.

Ku, Zhiliang; Rong, Yaoguang; Han, Hongwei

2013-10-01

242

Facile fabrication of mesoporous iron modified Al2O3 nanoparticles pillared montmorillonite nanocomposite: a smart photo-Fenton catalyst for quick removal of organic dyes.  

PubMed

A mesoporous iron modified Al2O3 nanoparticle pillared montmorillonite nanocomposite (mesoporous Fe/APM nanocomposite) was synthesized by using sodium exchanged montmorillonite by cation-exchange, gallery-templated synthesis and impregnation method. Formation of Al2O3 nanoparticles (Al2O3 NPs) having average particle size 5.20-6.50 nm within montmorillonite, formation of mesoporous Al2O3 NPs pillared montmorillonite (mesoporous APM) from montmorillonite and formation of a mesoporous Fe/APM nanocomposite signifies the present investigation. The roles of ammonia, CTAB, octyl amine and calcination temperature for fabrication of mesoporous Fe/APM nanocomposite were highly significant. Ammonia was used for post-synthesis treatment, which helped in the formation of micellar assemblies in the interlayer space. The materials were characterized by different techniques such as N2 adsorption-desorption study, which demonstrated the mesoporosity of the material. A transmission electron microscopy (TEM) image proves the morphology and size of the Al2O3 NPs and mesoporous Fe/APM nanocomposites. X-ray diffraction technique (XRD) describes the formation of the pillaring of the Al2O3 NPs within montmorillonite (APM). It has been noted that pure montmorillonite is a micro/mesoporous material. But after pillaring of Al2O3 NPs within the montmorillonite, mesoporosity developed, which is the vital aspect of present investigation. It was observed that the mesoporous Fe/APM nanocomposite has high photo-Fenton activity towards degradation of organic dyes such as acid blue (AB) and reactive blue (RB). Nearly 100% degradation took place within 30 minutes with high concentration of dye (500 mg L(-1)) by mesoporous 5 Fe/APM nanocomposite under ambient conditions. Small particle sizes of nanocomposite, quick reduction of Fe(III) and mesoporosity are the key points for proficient degradation of AB and RB. PMID:24002045

Pradhan, Amaresh C; Varadwaj, G Bishwa Bidita; Parida, K M

2013-11-14

243

Use of grape seed and its natural polyphenol extracts as a natural organic coagulant for removal of cationic dyes  

Microsoft Academic Search

Natural organic coagulants (NOCs) such as chitosan and Moringa oleifera seeds have been extensively characterized for potential application in water treatment as an alternative to metal-based coagulants. However, the action of both chitosan and M. oleifera seeds is mainly restricted to anionic organic pollutants because of their cationic functional groups affording poor cationic pollutant coagulation by electrostatic repulsion. In this

Jong-Rok Jeon; Eun-Ju Kim; Young-Mo Kim; Kumarasamy Murugesan; Jae-Hwan Kim; Yoon-Seok Chang

2009-01-01

244

Studies of the photoelectrochemistry of organic dyes using attenuated total-reflection techniques. Annual progress report, June 1, 1982-May 31, 1983  

SciTech Connect

Using a laser total internal reflection system (laser IRS), the energetic threshold has been mapped for photocurrent sensitized excited singlet dye molecules adsorbed on the surface of SrTiO/sub 3/ single crystals. The results, obtained in terms of the quantum efficiency of photocurrent production (phi), are compared with theory and implications summarized. Data are presented from an initial study of the photoxidation of triphenylmethane dyes at gold electrodes which utilized spectroelectrochemical internal reflection spectroscopy (spectroelectrochemical IRS). The progress in new dye sensitization experiments with triplets and dye aggregates is outlined.

Spitler, M.T.

1983-01-01

245

Photocatalytic degradation of organic dyes on visible-light responsive photocatalyst PbBiO{sub 2}Br  

SciTech Connect

The layered compound of lead bismuth oxybromide PbBiO{sub 2}Br, prepared by conventional solid-state reaction method, has an optical band gap of 2.3 eV, and possesses a good visible-light-response ability. The references, PbBi{sub 2}Nb{sub 2}O{sub 9}, TiO{sub 2-x}N{sub x}, BiOBr and BiOI{sub 0.8}Cl{sub 0.2}, which are excellent visible-light-response photocatalysts, were applied to comparatively understand the activity of PbBiO{sub 2}Br. Degradation of methyl orange and methylene blue was used to evaluate photocatalytic activity. The results show that PbBiO{sub 2}Br is more photocatalytically active than PbBi{sub 2}Nb{sub 2}O{sub 9}, TiO{sub 2-x}N{sub x} and BiOBr under visible light. - Graphical abstract: The as-prepared layered PbBiO{sub 2}Br with an optical band gap of 2.3 eV possesses a fair visible-light-response ability. The references, PbBi{sub 2}Nb{sub 2}O{sub 9}, TiO{sub 2-x}N{sub x}, BiOBr and BiOI{sub 0.8}Cl{sub 0.2}, were applied to comparatively understand the activity of PbBiO{sub 2}Br. Degradation of dyes was used to evaluate photocatalytic activity. The results show that PbBiO{sub 2}Br is more photocatalytically active than PbBi{sub 2}Nb{sub 2}O{sub 9}, TiO{sub 2-x}N{sub x} and BiOBr under visible light.

Shan Zhichao [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Department of Chemistry, East China Normal University, Shanghai 200062 (China); Wang Wendeng; Lin Xinping [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Ding Hanming [Department of Chemistry, East China Normal University, Shanghai 200062 (China)], E-mail: hmding@chem.ecnu.edu.cn; Huang Fuqiang [State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)], E-mail: huangfq@mail.sic.ac.cn

2008-06-15

246

Afferent and efferent connections of the pineal organ in the European sea bass Dicentrarchus labrax: a carbocyanine dye tract-tracing study.  

PubMed

The pineal organ of fish is a photosensitive structure that receives light information from the environment and transduces it into hormonal (rhythmic melatonin secretion) and neural (efferent projections/neurotransmitters) signals. In this study, we focused on this neural output. Thus, we performed a tract-tracing study using 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI), a fluorescent carbocyanine dye, in order to elucidate the efferent and afferent connections of the pineal organ in the European sea bass. The axonal transport of DiI revealed extensive bilateral projections in the sea bass brain. The efferent projections of the sea bass pineal organ reach the habenula, ventral thalamus, periventricular pretectum, central pretectal area, posterior tubercle and medial and dorsal tegmental areas. In addition, in this study we also examined the pinealopetal system in sea bass. This analysis demonstrated that the sea bass pineal organ receives central projections from neurons located, to a large extent, in brain areas innervated by pineal efferent projections, i.e. the thalamic eminence, habenula, ventral thalamus, dorsal thalamus, periventricular pretectum, posterior commissure, posterior tubercle and medial tegmental area. This study is the first description of pinealofugal projections in a representative of Perciformes, which constitutes a derived order within teleosts. Moreover, it represents the first evidence for the presence of pinealopetal neurons in the brain of a teleost species. Our findings, together with the analysis of retinal connections, represent a step forward in the understanding of the integration of photoperiodic signals into the central nervous system of sea bass. PMID:21921581

Servili, Arianna; Herrera-Pérez, Patricia; Yáñez, Julián; Muñoz-Cueto, José Antonio

2011-01-01

247

Dye laser amplifier  

DOEpatents

An improved dye laser amplifier is disclosed. The efficiency of the dye laser amplifier is increased significantly by increasing the power of a dye beam as it passes from an input window to an output window within the dye chamber, while maintaining the intensity of the dye beam constant. 3 figs.

Moses, E.I.

1992-12-01

248

Application of surface-enhanced Raman scattering (SERS) for the identification of anthraquinone dyes used in works of art  

SciTech Connect

Surface-enhanced Raman scattering (SERS) was investigated for applications in the analysis of anthraquinone dyes used in works of art. Two SERS procedures were developed and evaluated with three frequently used anthraquinone dyes, alizarin, carminic acid and lac dye. The first procedure involves coating a layer of silver nanoparticles directly on pieces of filter paper stained with the dyes of interest by thermal evaporation to induce SERS effect. In the second procedure, a SERS-active Ag-Al{sub 2}O{sub 3} substrate was prepared by spin-coating an alumina-nanoparticle layer onto a glass slide to provide the nanostructure of the substrate, followed by thermally evaporating a layer of silver nanoparticles on top of the alumina layer. Aliquots of dye solutions were delivered onto this substrate to be analyzed. Intense SERS spectra characteristic of alizarin, carminic acid and lac dye were obtained using both SERS procedures. The effects of two parameters, the concentration of the alumina suspension and the thickness of the silver nanoparticle layer on the performance of the Ag-Al{sub 2}O{sub 3} substrate were examined with alizarin as the model compound. Comparative studies were conducted between the Ag-Al{sub 2}O{sub 3} substrate and the SERS substrate prepared using Tollens reaction. The Ag-Al{sub 2}O{sub 3} substrate was shown to offer larger enhancement and improved reproducibility than the Tollens substrates. Finally, the potential applicability of the Ag-Al{sub 2}O{sub 3} substrate for the analysis of real artifact objects was illustrated by the identification of alizarin extracted from a small piece of textile dyed using traditional methods and materials. The limit of detection for alizarin was estimated to be 7 x 10{sup -15} g from tests performed on solutions of known concentration.

Chen, Kui [ORNL; Leona, Marco [ORNL; Yan, Fei [ORNL; Wabuyele, Musundi B [ORNL; Vo Dinh, Tuan [ORNL

2006-04-01

249

Low-temperature sintering for plastic dye-sensitized solar cells using conventional TiO2 paste containing organic binders  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells (DSSCs) require sintering of TiO2 photoelectrodes at 450 °C to 550 °C. However, high-temperature sintering is unfavorable because it limits the use of materials that cannot withstand high temperatures. In previous papers, we proposed a surface treatment of TiO2 photoelectrodes to reduce the sintering temperature from 500 °C to 250 °C using a dielectric barrier discharge and ultraviolet light from a low-pressure mercury lamp. In this study, we improved the surface treatment of TiO2 photoelectrodes to further reduce the sintering temperature from 250 °C to 150 °C using a conventional TiO2 paste that contains organic binders. The sintering temperature of 150 °C is critical because it is the maximum tolerable temperature of plastic substrates. The improved surface treatment is applied to both glass and plastic substrate DSSCs. The energy conversion efficiency of glass and plastic substrate DSSCs sintered at 150 °C using our improved surface treatment are approximately 110% and 80%, respectively, of that of glass substrate DSSCs fabricated using the conventional method sintered at 500 °C.

Zen, Shungo; Ishibashi, Yuta; Ono, Ryo

2014-05-01

250

Effect of different solvents on the performance of organic light-emitting device based on red-fluorescent ACY dye by spin coating method  

NASA Astrophysics Data System (ADS)

A small-molecular red-fluorescent dye of [7-diethylamino-3-(2-thienyl)chronmen-2-ylidene]-2,2-dicyanoviny-lamine (ACY) has been blended into blue-emitting poly(N-vinylcarbazole) (PVK) by using different solvents of chloroform and 1,2-dichloroethane. Photoluminescence characteristic of solvent effects were investigated mainly from the aspect of solvent polarity. To demonstrate the solvent effects in organic light emitting devices (OLEDs), devices with a structure of indium-tin-oxide (ITO)/PVK: ACY (x wt %)/tris(8-quinolinolato) aluminum (Alq3)/Mg: Ag were fabricated, in which the weight doping ratios are x = 0.3, 0.5 and 0.7. Using spin coating method, a blending system of PVK: ACY is dissolved in both chloroform and 1,2-dichloroethane with various doping concentrations. As a result, by choosing chloroform as solvent, a high electroluminescent (EL) performance device with a maximum luminance of 7698 cd/m2 at a driving voltage of 15.5 V was obtained, with a concentration proportion of PVK: ACY at 1000: 7. In the EL spectra of the OLEDs, red and green fluorescence of ACY and Alq3 were detected. It was found that by using 1,2-dichloroethane as a solvent, fluorescent quenching emerged with the enhancement of doping concentration. Energy transfer and Alq3 cations quencher theories were used to discuss different solvent effects on OLEDs.

Yu, Shuangjiang; Yu, Junsheng; Wang, Hong; Jiang, Yadong

2010-05-01

251

Microwave-enhanced synthesis of magnetic porous covalent triazine-based framework composites for fast separation of organic dye from aqueous solution.  

PubMed

A novel type of magnetic porous carbonaceous polymeric material, CTF/Fe(2)O(3) composite (CTF = covalent triazine-based framework), has been synthesized by a facile microwave-enhanced high-temperature ionothermal method. By selecting ZnCl(2) as a reaction medium and the Lewis acid catalyst, and choosing FeCl(3)·6H(2)O as an iron oxide precursor, a series of CTF/Fe(2)O(3) composites with different ?-Fe(2)O(3) contents has been prepared in 60 min. The resulting samples were characterized by the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibration sample magnetometer (VSM), and N(2) sorption-desorption isotherms. The obtained CTF/Fe(2)O(3) composites exhibit high surface areas (930-1149 m(2) g(-1)), and their saturation magnetizations at 300 K vary from 1.1 to 5.9 emu g(-1), depending respectively on different Fe(2)O(3) contents (6.43-12.43 wt%) in the CTF/Fe(2)O(3) composites. The CTF/Fe(2)O(3) composites were applied to remove organic dye from aqueous solution by selecting methyl orange as a model molecule, and both high adsorption capacity (291 mg g(-1), corresponding to 0.889 mmol g(-1)) and fast adsorption kinetics (k(ads) = 4.31 m(2) mg(-1) min(-1)) were observed. PMID:21159428

Zhang, Wang; Liang, Fei; Li, Cun; Qiu, Ling-Guang; Yuan, Yu-Peng; Peng, Fu-Min; Jiang, Xia; Xie, An-Jian; Shen, Yu-Hua; Zhu, Jun-Fa

2011-02-28

252

Characterization of anthocyanin based dye-sensitized organic solar cells (DSSC) and modifications based on bio-inspired ion mobility improvements  

NASA Astrophysics Data System (ADS)

The worldwide electrical energy consumption will increase from currently 10 terawatts to 30 terawatts by 2050. To decrease the current atmospheric CO2 would require our civilization to develop a 20 terawatts non-greenhouse emitting (renewable) electrical power generation capability. Solar photovoltaic electric power generation is thought to be a major component of proposed renewable energy-based economy. One approach to less costly, easily manufactured solar cells is the Dye-sensitized solar cells (DSSC) introduced by Greatzel and others. This dissertation describes the work focused on improving the performance of DSSC type solar cells. In particular parameters affecting dye-sensitized solar cells (DSSC) based on anthocyanin pigments extracted from California blackberries (Rubus ursinus) and bio-inspired modifications were analyzed and solar cell designs optimized. Using off-the-shelf materials DSSC were constructed and tested using a custom made solar spectrum simulator and photoelectric property characterization. This equipment facilitated the taking of automated I-V curve plots and the experimental determination of parameters such as open circuit voltage (V OC), short circuit current (JSC), fill factor (FF), etc. This equipment was used to probe the effect of various modifications such as changes in the annealing time and composition of the of the electrode counter-electrode. Solar cell optimization schemes included novel schemes such as solar spectrum manipulation to increase the percentage of the solar spectrum capable of generating power in the DSSC. Solar manipulation included light scattering and photon upconversion. Techniques examined here focused on affordable materials such as silica nanoparticles embedded inside a TiO2 matrix. Such materials were examined for controlled scattering of visible light and optimize light trapping within the matrix as well as a means to achieve photon up-energy-conversion using the Raman effect in silica nano-particles (due to a strong Raman anti-Stoke scattering probability). Finally, solutions to the mobility problem of organic photovoltaics were explored. The solutions examined here were based on the bio-inspired neural ionic conduction were nature has overcome the poor ionic mobility in solutions (D ˜ 10-5cm2/ s) to achieve amazingly fast ionic conduction using non-electric field energy gradients. Electric-permeability-graded layers with possibility to create an energy gradient that helps the diffusion DSSC electrolyte diffusion were explored in this work.

Mawyin, Jose Amador

253

Just Dyeing to Find Out.  

ERIC Educational Resources Information Center

Presents a multidisciplinary unit on natural dyes designed to take advantage of the natural curiosity of middle school students. Discusses history of dyes, natural dyes, preparation of dyes, and the dyeing process. (JRH)

Monhardt, Becky Meyer

1996-01-01

254

Hair Dye and Hair Relaxers  

MedlinePLUS

... Bad Reaction to Cosmetics? Tell FDA Cosmetics Tips Hair Dye and Hair Relaxers En Español Hair dye is ... hair relaxers. Hair Dyes Hair Relaxers Report Problems Hair Dyes There are different types of hair dyes used ...

255

Review: Dye sensitized solar cells based on natural photosensitizers  

Microsoft Academic Search

The performance of dye sensitized solar cells is mainly based on the dye as a sensitizer. Natural dyes have become a viable alternative to expensive and rare organic sensitizers because of its low cost, easy attainability, abundance in supply of raw materials and no environment threat. Various components of a plant such as the flower petals, leaves and bark have

Monishka Rita Narayan

256

Studies of the photoelectrochemistry of organic dyes using attenuated total reflection techniques. Annual progress report, June 1, 1983-May 31, 1984  

SciTech Connect

Employing two experimenal arrangements of internal reflection spectroscopy, work has been completed which define the energetic threshold for sensitized photocurrent and explore the photochemistry of J aggregate sensitization of semiconductor electrodes by cyanine dyes. The threshold measurements were made using a laser total internal reflection system (laser ATR); the aggregate experiments were done using internal reflection spectroscopy with white light (spectroelectrochemical IRS). A summary is made of the progress in measurements with H-band aggregates of cyanine dyes and triplet state studies with xanthene dyes. The direction of research during the remainder of the contract year is outlined.

Spitler, M.T.

1983-11-01

257

Suitability of Polymeric Media In Solid State Dye Lasers  

NASA Astrophysics Data System (ADS)

Solid hosts doped with organic dyes are suitable for tunable solid state lasers because of large band width in visible region. Moreover they also overcome the problems of toxicity and limited tunability due to liquid solutions of the dyes. We report fluorescence spectra of different rhodamine dyes in different solid hosts which can be quite helpful in choosing the proper solid host for solid state dye lasers.

Sharma, Amit; Saini, G. S. S.

2011-12-01

258

Studies of the photoelectrochemistry of organic dyes using attenuated total-reflection techniques. Annual progress report, June 1, 1981-May 31, 1982  

SciTech Connect

A laser total internal reflection system (laser IRS) has been used to study the photooxidation of cyanine dyes at ZnO, TiO/sub 2/, and SrTiO/sub 3/ single crystal electrodes. The quantum efficiency for photocurrent production, phi/sub p/, was found to be approx. 10/sup -3/ at these electrodes for the monomer form of the dye. Aggregates of the dyes were also found to play a significant role with an oxidation mechanism which differs from the monomer. Energetic thresholds for electron injection into the semiconductor predicted by theory were confirmed for SrTiO/sub 3/ and TiO/sub 2/. A spectroelectrochemical total internal reflection spectroscopy system (spectroelectrochemical IRS) has been constructed to study the photooxidation of triphenylmethane dyes at gold electrodes. Experimentation with this system is in progress.

Spitler, M.T.

1982-01-01

259

Comparative study of UV\\/TiO 2, UV\\/ZnO and photo-Fenton processes for the organic reactive dye degradation in aqueous solution  

Microsoft Academic Search

In this study advanced oxidation processes (AOPs), UV\\/TiO2, UV\\/ZnO and photo-Fenton, were applied in order to degrade C.I. Reactive Red 45 (RR45) dye in aqueous solution. The effects of key operating parameters, such as initial pH, catalyst and hydrogen peroxide dosage as well as the effect of initial dye concentration on decolorization and mineralization extents were studied. Primary objective was

Igor T. Peternel; Natalija Koprivanac; Ana M. Lon?ari? Boži?; Hrvoje M. Kuši?

2007-01-01

260

Synthesis, Photophysics, Electrochemistry and Electrogenerated Chemiluminescence of PEG-Modified BODIPY dyes in Organic and Aqueous Solutions  

PubMed Central

A set polyethylene glycol (PEG) appended BODIPY architectures (BOPEG1 – BOPEG3) have been prepared and studied in CH2Cl2, H2O:CH3CN (1:1) and aqueous solutions. BOPEG1 and BOPEG2 both contain a short PEG chain and differ in substitution about the BODIPY framework. BOPEG3 is comprised of a fully substituted BODIPY moiety linked to a PEG polymer that is roughly 13 units in length. The photophysics and electrochemical properties of these compounds have been thoroughly characterized in CH2Cl2 and aqueous CH3CN solutions. The behavior of BOPEG1 – BOPEG3 correlates with established rules of BODIPY stability based on substitution about the BODIPY moiety. ECL for each of these compounds was also monitored. BOPEG1, which is unsubstituted at the 2- and 6-positions dimerized upon electrochemical oxidation while BOPEG2, which contains ethyl groups at the 2- and 6-positions, was much more robust and served as an excellent ECL luminophore. BOPEG3 is highly soluble in water due to the long PEG tether and demonstrated modest ECL activity in aqueous solutions using tri-n-propylamine (TPrA) as a coreactant. As such, BOPEG3 represents the first BODIPY derivative that has been shown to display ECL in water without the need for an organic cosolvent, and marks an important step in the development of BODIPY based ECL probes for various biosensing applications.

Nepomnyashchii, Alexander B.; Pistner, Allen J.; Bard, Allen J.; Rosenthal, Joel

2013-01-01

261

Solvatochromic behavior of chiral mesoporous metal-organic frameworks and their applications for sensing small molecules and separating cationic dyes.  

PubMed

Two anionic metal-organic frameworks (MOFs) with 1D mesoporous tubes (1) and chiral mesoporous cages (2) have been rationally constructed by means of a predesigned size-extended hexatopic ligand, namely, 5,5',5''-(1,3,5-triazine-2,4,6-triyl)tris- (azanediyl)triisophthalate (TATAT). Charge neutrality is achieved by protonated dimethylamine cations. Notably, the two MOFs can be used to separate large molecules based on ionic selectivity rather than the size-exclusion effect so far reported in the literature. Owing to the imino triazine backbone and carboxyl groups of the hexatopic ligand, which provide important host-guest interactions, rare solvatochromic phenomena of 1 and 2 are observed on incorporating acetone and ethanol guests. Furthermore, guest-dependent luminescence properties of compound 2 were investigated, and the results show that luminescence intensity is significantly enhanced in toluene and benzene, while quenching effects are observed in acetone and ethanol. Thus, compound 2 may be a potential material for luminescent probes. PMID:23361638

Sun, Chun-Yi; Wang, Xin-Long; Qin, Chao; Jin, Jun-Ling; Su, Zhong-Min; Huang, Peng; Shao, Kui-Zhan

2013-03-11

262

Predicting azo dye toxicity  

Microsoft Academic Search

Literature regrading azo dye carcinogenicity was examined to establish, if possible, guidelines to predict the human health risks of new azo dyes. Three different mechanisms for azo dye carcinogenicity were identified, all involving metabolic activation to reactive electrophilic intermediates that covalently bind DNA. In the order of decreasing number of published references, these mechanisms are 1. Azo dyes that are

Mark A. Brown; Stephen C. De Vito

1993-01-01

263

On the intrinsic photophysics of indigo: a time-resolved photoelectron spectroscopy study of the indigo carmine dianion.  

PubMed

The intrinsic photophysics of indigo has been studied using gas-phase time-resolved photoelectron imaging of the indigo carmine dianion (InC(2-)). The action spectrum reveals that the gas-phase absorption spectrum arising from the S(1) <-- S(0) transition in InC(2-) has a similar solvent shift to that of neutral indigo. Femtosecond spectroscopy shows that the S(1) state decays on a 1.4 ps timescale. Through isotopic substitution, the primary mechanism on the S(1) excited state can be assigned to an intra-molecular proton transfer, which is the same as that which has been observed in solution. However, the excited state lifetime is significantly shorter in vacuum. These similarities and differences are discussed in terms of recent theoretical investigations of the S(1) excited state of indigo. PMID:24734261

Chatterley, Adam S; Horke, Daniel A; Verlet, Jan R R

2012-12-14

264

Accurate simulation of optical properties in dyes.  

PubMed

Since Antiquity, humans have produced and commercialized dyes. To this day, extraction of natural dyes often requires lengthy and costly procedures. In the 19th century, global markets and new industrial products drove a significant effort to synthesize artificial dyes, characterized by low production costs, huge quantities, and new optical properties (colors). Dyes that encompass classes of molecules absorbing in the UV-visible part of the electromagnetic spectrum now have a wider range of applications, including coloring (textiles, food, paintings), energy production (photovoltaic cells, OLEDs), or pharmaceuticals (diagnostics, drugs). Parallel to the growth in dye applications, researchers have increased their efforts to design and synthesize new dyes to customize absorption and emission properties. In particular, dyes containing one or more metallic centers allow for the construction of fairly sophisticated systems capable of selectively reacting to light of a given wavelength and behaving as molecular devices (photochemical molecular devices, PMDs).Theoretical tools able to predict and interpret the excited-state properties of organic and inorganic dyes allow for an efficient screening of photochemical centers. In this Account, we report recent developments defining a quantitative ab initio protocol (based on time-dependent density functional theory) for modeling dye spectral properties. In particular, we discuss the importance of several parameters, such as the methods used for electronic structure calculations, solvent effects, and statistical treatments. In addition, we illustrate the performance of such simulation tools through case studies. We also comment on current weak points of these methods and ways to improve them. PMID:19113946

Jacquemin, Denis; Perpète, Eric A; Ciofini, Ilaria; Adamo, Carlo

2009-02-17

265

Chalcogenopyrylium Dyes as Differential Modulators of Organic Anion Transport by Multidrug Resistance Protein 1 (MRP1), MRP2, and MRP4  

PubMed Central

Multidrug resistance proteins (MRPs) mediate the ATP-dependent efflux of structurally diverse compounds, including anticancer drugs and physiologic organic anions. Five classes of chalcogenopyrylium dyes (CGPs) were examined for their ability to modulate transport of [3H]estradiol glucuronide (E217?G; a prototypical MRP substrate) into MRP-enriched inside-out membrane vesicles. Additionally, some CGPs were tested in intact transfected cells using a calcein efflux assay. Sixteen of 34 CGPs inhibited MRP1-mediated E217?G uptake by >50% (IC50 values: 0.7–7.6 µM). Of 9 CGPs with IC50 values ?2 µM, two belonged to class I, two to class III, and five to class V. When tested in the intact cells, only 4 of 16 CGPs (at 10 µM) inhibited MRP1-mediated calcein efflux by >50% (III-1, V-3, V-4, V-6), whereas a fifth (I-5) inhibited efflux by just 23%. These five CGPs also inhibited [3H]E217?G uptake by MRP4. In contrast, their effects on MRP2 varied, with two (V-4, V-6) inhibiting E217?G transport (IC50 values: 2.0 and 9.2 µM) and two (V-3, III-1) stimulating transport (>2-fold), whereas CGP I-5 had no effect. Strikingly, although V-3 and V-4 had opposite effects on MRP2 activity, they are structurally identical except for their chalcogen atom (Se versus Te). This study is the first to identify class V CGPs, with their distinctive methine or trimethine linkage between two disubstituted pyrylium moieties, as a particularly potent class of MRP modulators, and to show that, within this core structure, differences in the electronegativity associated with a chalcogen atom can be the sole determinant of whether a compound will stimulate or inhibit MRP2.

Myette, Robert L.; Conseil, Gwenaelle; Ebert, Sean P.; Wetzel, Bryan; Detty, Michael R.

2013-01-01

266

Anthraquinone dyes decolorization capacity of anamorphic Bjerkandera adusta CCBAS 930 strain and its HRP-like negative mutants.  

PubMed

Cultures of the anamorphic fungus Bjerkandera adusta CCBAS 930 decolorizing, in stationary cultures, 0.01 % solutions of carminic acid and Poly R-478, were characterised by a strong increase in the activity of the horseradish peroxidase (HRP-like) and manganese-dependent peroxidase (MnP) at a low activity of lignin peroxidase. Genotypically modified mutants of B. adusta CCBAS 930: 930-5 and 930-14, with total or partial loss of decolorization capabilities relative to anthraquinonic dyes, showed inhibition of the activity of HRP-like peroxidase and MnP. Whereas, compared to the parental strain, in the mutant cultures there was an increase in the activity of lignin peroxidase and laccase. The paper presents a discussion of the role of the studied enzymatic activities in the process of decolorization of anthraquinonic dyes by the strain B. adusta CCBAS 930. PMID:24415463

Korni??owicz-Kowalska, Teresa; Rybczy?ska, Kamila

2014-06-01

267

Visible-Light-Driven, Tunable, Photoelectrochemical Performance of a Series of Metal-Chelate, Dye-Organized, Crystalline, CdS Nanoclusters.  

PubMed

CdS nanoclusters of four different sizes were integrated with ruthenium-complex dyes. The cluster-dye crystalline composites, [Cd4 (SPh)10 ][Ru(bpy)3 ], [Cd8 S(SPh)16 ][Ru(bpy)3 ], [Cd8 S(SPh)13 ?Cl?(CH3 OCS2 )2 ][Ru(phen)3 ], [Cd17 S4 (SPh)28 ][Ru(bpy)3 ], and [Cd32 S14 (SPh)40 ][Ru(phen)3 ]2 (phen=1,10-phenanthroline and bpy=bipyridine), show intense absorption in the visible-light region. They also exhibit size-dependent photocurrent responses under the illumination of visible light. The photocurrent increases with increased cluster size. The dyes also have significant influence on the photocurrent generation of the composite. PMID:24890989

Liu, Yang; Lin, Qipu; Zhang, Qichun; Bu, Xianhui; Feng, Pingyun

2014-07-01

268

Role of Rare Earth Oxide Nanoparticles (CeO2 and La 2O 3) in Suppressing the Photobleaching of Fluorescent Organic Dyes.  

PubMed

Aqueous solutions with Rhodamine dye, and fluorescently labeled polymer samples of fibrin and collagen were mixed with aqueous dispersions of cerium oxide, lanthanum oxide, iron (II) oxide nanoparticles, and OxyFluor, a commonly used reagent for suppressing photobleaching. From time dependent studies of the fluorescence from these samples, we observed that the dyes in samples containing rare earth oxide nanoparticles exhibited significantly slower rates of fluorescence decay compared to control samples without additives, or containing OxyFluor or iron oxide nanoparticles. We posit that this may be related to the oxygen free radical scavenging properties of rare earth oxides. PMID:24706286

Guha, Anubhav; Basu, Anindita

2014-05-01

269

Enhanced photocatalytic and adsorptive degradation of organic dyes by mesoporous Cu/Al2O3-MCM-41: intra-particle mesoporosity, electron transfer and OH radical generation under visible light.  

PubMed

Mesoporous Cu/Al(2)O(3)-MCM-41 composite was synthesized by two step processes; in situ incorporation of high surface area mesoporous Al(2)O(3) (MA) into the framework of MCM-41 (in situ method) followed by impregnation of Cu(II) by incipient wetness method. The interesting thing is that starch was used for the first time as template for the preparation of high surface area MA. To evaluate the structural and electronic properties, these catalysts were characterized by low angle X-ray diffraction (LXRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), UV-vis DRS, FTIR and photoluminescent (PL) spectra. The various cationic dye such as methylene blue (MB), methyl violet (MV), malachite green (MG) and rhodamine 6G (Rd 6G) of high concentration 500 mg L(-1) were degraded and adsorbed very efficiently (100%) using the 5 Cu/Al(2)O(3)-MCM-41 composite within 30 and 60 min, respectively. The high and quick removal of such concerted cationic organic dyes and also mixed dyes (MB+MV+MG+Rd 6G) by means of photocatalysis/adsorption is basically due to the combined effect three characteristics of synthesized mesoporous 5 Cu/Al(2)O(3)-MCM-41 composite. These characteristics are intra-particle mesoporosity, electron transfer and ?OH radical generation under solar light. PMID:21681290

Pradhan, Amaresh C; Parida, K M; Nanda, Binita

2011-07-28

270

Method of dye removal for the textile industry  

DOEpatents

The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention comprises using an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.

Stone, Mark L. (Idaho Falls, ID)

2000-01-01

271

Influence of physicochemical–electronic properties of transition metal ion doped polycrystalline titania on the photocatalytic degradation of Indigo Carmine and 4-nitrophenol under UV\\/solar light  

Microsoft Academic Search

To understand the role of dopant inside TiO2 matrix, anatase TiO2 was doped with transition metal ions like Mn2+, Fe3+, Ru3+ and Os3+ having unique half filled electronic configuration and their photocatalytic activity was probed in the degradation of Indigo Carmine (IC) and 4-nitrophenol (NP) under UV\\/solar light. For comparison, TiO2 was also doped with V5+, Ni2+ and Zn2+ metal

L. Gomathi Devi; S. Girish Kumar

2011-01-01

272

Molecular architecture in cyanine dye aggregates at the air-water interface. Effect of monolayer composition and organization on fluorescent behavior  

SciTech Connect

The fluorescence behavior of an amphiphatic oxacyanine dye and its thiacyanine analogue has been investigated in spread monolayers at the air-water interface. J-aggregate formation as a function of area/(dye molecule) was monitored by spectral changes in pure dye monolayers and in 1:1 mixtures of dye with various fatty acid coaggregates. Simultaneously, the thermodynamic behavior of these systems was characterized by the associated surface pressure-area isotherms. In all cases, J-aggregate formation may be related to a phase transition in the isotherm. The intensity of aggregate fluorescence is found to be inversely related to the work, ..delta..W, of compression of the monolayer through the transition. Inclusion of the fatty acid coaggregate was shown to facilitate J-aggregate formation in the order stearic > elaidic > oleic. Both fluorescence and thermodynamic data indicate more extensive aggregate formation in the thiacyanine systems. Aside from the paramount role played by the chromophore-chromophore interactions in determining J-aggregate phenomena, this study suggests important contributions from dispersion forces involving the long hydrocarbon moieties. 13 refs., 10 figs.

Vaidyanathan, S.; Patterson, L.K.; Moebius, D.; Gruniger, H.R.

1985-01-31

273

Microencapsulated Fluorescent Dye Penetrant.  

National Technical Information Service (NTIS)

Microencapsulated fluorescent dye pentrant materials were evaluated for feasibility as a technique to detect cracks on metal surfaces when applied as a free flowing dry powder. Various flourescent dye solutions in addition to a commercial penetrant (Zyglo...

S. Allinikov

1979-01-01

274

Fluorescent dye binding peptides  

US Patent & Trademark Office Database

The present invention is directed to novel polypeptides, termed fluorettes, that bind with high avidity to fluorophore dyes. The peptides find use in a variety of methods and approaches involving fluorophore dyes.

2004-06-08

275

Optofluidic dye lasers  

Microsoft Academic Search

Optofluidic dye lasers are microfabricated liquid dye lasers enabled by the microfluidics technology. The integration of dye\\u000a lasers with microfluidics not only facilitates the implementation of complete “lab-on-a-chip” systems, but also allows the\\u000a dynamical control of the laser properties which is not achievable with solid-state optical components. We review the recent\\u000a demonstrations of on-chip liquid dye lasers and some of

Zhenyu Li; Demetri Psaltis

2008-01-01

276

Functional assessment for predicting charge-transfer excitations of dyes in complexed state: a study of triphenylamine-donor dyes on titania for dye-sensitized solar cells.  

PubMed

Time-dependent density functional theory (TD-DFT) was employed to calculate the UV/vis spectra for three of the triphenylamine (TPA)-donor dyes, TC1, L1, and LJ1, in isolation as well as when complexed with a titania nanoparticle. TPA-donor dyes are a class of promising organic dyes for use in dye-sensitized solar cells (DSSCs). The three dyes studied here are among the smallest of these molecules and provide important insight into the entire series of TPA dyes that are being explored as possible sensitizers in titania-based DSSCs. An attempt to calculate the optical spectra for these dyes within the B3LYP approximation to the exchange correlation functional produces erroneous results. However, Coulomb attenuated approximation (CAM-B3LYP) captures the correct photophysics of the dyes and produces more accurate charge-transfer excitation energies of their complexes with titania. This work shows that the extent to which a given approximation fails or succeeds to correctly predict the charge-transfer excitation energies in the isolated dyes is propagated in that it fails (or succeeds) to correctly predict the values of the excitation energies for the complexes. It is, therefore, important to determine the most appropriate functional for a dye before considering it in more complicated structures such as dye-titania complexes. PMID:23237270

Dev, Pratibha; Agrawal, Saurabh; English, Niall J

2013-03-14

277

Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes  

NASA Astrophysics Data System (ADS)

This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed on mesoporous Titanium Dioxide (TiO2) which has been optimized in our laboratory. The best dyes light absorbance and performance obtained from papaya leaf as chlorophyll dyes that gives two peaks at 432 nm and 664 nm from UV-Vis Spectrophotometry and performance under 100 mW/cm2 Xenon light solar simulator gives VOC = 0.566 Volt, JSC = 0.24 mA/cm2, Fill Factor = 0.33, and efficiency of energy conversion 0,045%.

Yuliarto, Brian; Fanani, Fahiem; Fuadi, M. Kasyful; Nugraha

2010-10-01

278

The process of the reduction of azo dyes used in dyeing textiles on the basis of infrared spectroscopy analysis  

Microsoft Academic Search

Nowadays the world observes a widespread campaign against the use in yarn of dangerous, carcinogenic amines which penetrate human organisms. Their source in organisms is the process of biological reduction of azo dyes which are used in dyeing yarn. The current obligatory methods of aromatic amine identification are the widely understood chromatographic methods. In this work, the identification of amines

A. Pielesz

1999-01-01

279

The influence of Yb, B, and Ga-doped Er3+:Y3Al5O12 on solar light photocatalytic activity of TiO2 in degradation of organic dyes  

NASA Astrophysics Data System (ADS)

Five up-conversion luminescence agents (Er3+:Y3Al5O12, Er3+:Yb n Y3 - n Al5O12, Er3+:Y3B a Al5 - a O12, Er3+:Y3Ga b Al5 - b O12, and Er3+:Yb n Y3 - n B a Ga b Al5 - a - b O12) were synthesized using sol-gel method and then the corresponding coated composites (Er3+:Y3Al5O12/TiO2, Er3+:Yb n Y3- n Al5O12/TiO2, Er3+:Y3B a Al5 - a O12/TiO2, Er3+:Y3Ga b Al5 - b O12/TiO2, and Er3+:Yb n Y3 - n B a Ga b Al5 - a - b O12/TiO2) as photocatalysts were prepared by sol-gel coating process. The XRD and SEM were used to confirm the crystalline phase and surface morphology. The UV-vis absorption and fluorescence-emission spectra were used to research the effect of doping category and amount on the up-conversion emission ability. The photocatalytic activities were detected through the degradation of Acid Red B dye in aqueous solution. Some key parameters of catalyst amount and initial concentration of organic dye on solar light photocatalytic degradation were also examined. The extensive feasibility of prepared photocatalysts in solar light degradation was detected by other organic dyes. The results suggest that the photocatalysts can be widely used in sewage treatment.

Wang, J.; Li, Y.; Wang, J.; Zhang, L.; Gao, J. Q.; Wang, B. X.; Yang, Q.; Fan, P.

2014-01-01

280

Optimization of Luminescent Solar Concentrators Using a Triple Dye System  

NASA Astrophysics Data System (ADS)

A possible alternative to the expensive photovoltaic cell (PVC) is the Luminescent Solar Concentrator (LSC). A LSC is a flat, translucent plate that absorbs sunlight through embedded, highly fluorescent chromophores. About 74 percent of the fluorescence is concentrated via total internal reflection at the edges of the LSC where PVCs convert it to electricity. Cost savings are realized through the reduced area of PVC material. A typical LSC employs a single organic dye, limiting the amount of light absorbed. A multiple dye LSC absorbs more light resulting in greater optical efficiency. We report on the performance of LSCs made with one, two, or three dyes in a 20 micron thick polymer layer on a glass substrate. By varying the relative concentrations of the dyes contained within the film, fluorescence resonance energy transfer between the dyes was optimized. The triple dye LSC showed a 36 percent increase in power over that of our best single dye LSC.

Wittmershaus, Bruce P.; Bailey, Sheldon T.; Lokey, Gretchen E.; Zhang, Yu-Zhong

2004-03-01

281

Two photon absorption energy transfer in the light-harvesting complex of photosystem II (LHC-II) modified with organic boron dye  

NASA Astrophysics Data System (ADS)

The plant light-harvesting complexes of photosystem II (LHC-II) play important roles in collecting solar energy and transferring the energy to the reaction centers of photosystems I and II. A two photon absorption compound, 4-(bromomethyl)-N-(4-(dimesitylboryl)phenyl)-N-phenylaniline (DMDP-CH2Br), was synthesized and covalently linked to the LHC-II in formation of a LHC-II-dye complex, which still maintained the biological activity of LHC-II system. Under irradiation with femtosecond laser pulses at 754 nm, the LHC-II-dye complex can absorb two photons of the laser light effectively compared with the wild type LHC-II. The absorbed excitation energy is then transferred to chlorophyll a with an obvious fluorescence enhancement. The results may be interesting and give potentials for developing hybrid photosystems.

Chen, Li; Liu, Cheng; Hu, Rui; Feng, Jiao; Wang, Shuangqing; Li, Shayu; Yang, Chunhong; Yang, Guoqiang

2014-07-01

282

Influence of Exposure to Imidacloprid on Survivorship, Reproduction and Vitellin Content of the Carmine Spider Mite, Tetranychus cinnabarinus  

PubMed Central

Occasional reports linking neonicotinoid insecticide applications to field population outbreaks of the spider mite have been a topic of concern for integrated pest management programs. To elucidate the impacts of a neonicotinoid insecticide on the carmine spider mite, Tetranychus cinnabarinus Boisduval (Acari: Tetranychidae), the survivorship, reproduction, and vitellin contents of the mite were investigated after exposure to various concentrations of imidacloprid on the V. unguiculata leaf discs at 25°C, 80% RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the field-relevant dose of imidacloprid did not significantly affect the hatch rate of eggs or pre-imaginal survivorship of the mite, while sublethal doses of imidacloprid, previously determined for Myzus persicae, led to a significant increase in the hatch rate of eggs and pre-imaginal survivorship of the mite compared to the untreated control. Adult longevity and fecundity of T. cinnabarinus for imidacloprid-treated populations were slightly prolonged and increased, respectively, but the difference from the untreated control was not significant. The vitellin content in eggs increased significantly after exposure to imidacloprid. Imidacloprid may be one of the major reasons for the outbreak of T. cinnabarinus in the field.

Zeng, Chun-Xiang; Wang, Jin-Jun

2010-01-01

283

Organic solvent based TiO 2 dispersion paste for dye-sensitized solar cells prepared by industrial production level procedure  

Microsoft Academic Search

In order to prepare the TiO2 liquid dispersions for the electrodes of dye-sensitized solar cells with industrial mass production level at a reasonable\\u000a cost, the present study investigates the preparation of TiO2 liquid dispersions by a general industrial dispersion technique using readily available P25. To determine the TiO2 dispersion offering the best light–electricity energy conversion efficiency, the suitability of various

Ryohei Mori; Tsutomu Ueta; Kazuo Sakai; Yasuhiro Niida; Yasuko Koshiba; Li Lei; Katsuhiko Nakamae; Yasukiyo Ueda

2011-01-01

284

Modification of TiO2 Electrode with Organic Silane Interposed Layer for High-Performance of Dye-Sensitized Solar Cells.  

PubMed

Back electron transfer from the TiO2 electrode surface to the electrolyte is the main reason behind the low-open circuit potential (Voc) and the low-fill factor (FF) of the dye-sensitized solar cells (DSSCs). Modifications to the TiO2 electrode, fabricated using {010}-faceted TiO2 nanoparticles with six different kinds of silane, are reported to decrease the back electron transfer on the TiO2 surface. The effect of alkyl chain length of hydrocarbon silanes and fluorocarbon silanes on adsorption parameters of surface coverage and adsorption constant, interfacial resistance, and photovoltaic performances were investigated. Adsorption isotherms, impedance analysis, and photovoltaic measurements were used as the investigation techniques. The reduction of back electron transfer depended on the TiO2 surface coverage by silane, alkyl chain length, and the molecular structure of the silane. Even though Voc and FF were improved, significant reduction in short-circuit photocurrent density (Jsc) was observed after silanization because of desorption of dye during silanization. A new approach, sequential adsorption process of silane and dye, was introduced to enhance Voc and FF without lowering Jsc. Heptadecafluorodecyl trimethoxy-silane showed the highest coverage on the surface of the TiO2 and had the highest effect on the performance improvement of the DSSC, where Voc, FF, and efficiency (?) were improved by 22, 8.0, and 22%, respectively. PMID:24684283

Sewvandi, Galhenage A; Tao, Zhuoqi; Kusunose, Takafumi; Tanaka, Yasuhiro; Nakanishi, Shunsuke; Feng, Qi

2014-04-23

285

Laser ablation of dyes  

NASA Astrophysics Data System (ADS)

High density 50 ?s pulses of the UV dyes PPF, POPOP and BBO and of two dyes in the visible region, Xanthen N92 and Fluorol 7GA were generated by laser ablation. Dye powders were pressed with 7800 kp/cm 2 in round pellets which were ablated by exposure to KrF excimer laser radiation (248 nm) at a fluence of 100 mJ/cm 2. The ablation cloud was optically activated with a XeCl excimer laser. Its fluorescence spectrum was measured and was identified as a dye vapour fluorescence spectrum by comparison to conventional dye solution and dye vapour spectra. The dye cloud is not deflected in an electric field (10 6 V/m). By changing the delay time between the ablation laser and the focused activation laser, the velocity distribution of the ablated dye was measured. Its maximum is at 600 m/s for PPF. Knowing the thickness of the ablated dye layer per shot (300 Å) and the size of the ablation cloud (pictures of a video camera), one can estimate the maximum density of the dye in the gas pulse to be 10 -5 mol/ l in the range of concentration of lasing dyes. However, no lasing was observed up to now.

Späth, M.; Stuke, M.

1992-01-01

286

Application of response surface methodology to optimize decolourization of dyes by the laccase-mediator system.  

PubMed

Response surface methodology (RSM) was applied to optimize the decolourization of 3 dyes belonging to 3 dye families such as reactive black 5 (diazoic), indigo carmine (indigoid) and aniline blue (anthraquinonic). Crude laccase from Trametes trogii and the laccase-mediator 1-hydroxybenzotriazole (HBT) were used in this study. Box-Behnken design using RSM with six variables namely pH, temperature, enzyme concentration, HBT concentration, dye concentration and incubation time was used in this study to optimize significant correlation between the effects of these variables on the decolourization of reactive black 5 (RB5), indigo carmine (IC) and aniline blue (AB). The optimum of pH, temperature, laccase, HBT, RB5 and reaction time were 4.5, 0.5 U ml(-1), 0.5 mM, 100 mg ml(-1) and 150 min respectively, for a maximum decolourization of RB5 (about 92.92% ± 7.21). Whereas, the optimum decolourization conditions of both IC (99.76% ± 7.75) and AB (98.44% ± 10) were: pH 4.5, temperature of 45 °C, enzyme concentration of 0.1 U ml(-1) and 0.5 U ml(-1), HBT concentration of 0.9 mM and 0.5 mM, dye concentration of 60 mg l(-1) and reaction time of 150 and 90 min, respectively. The experimental values were in good agreement with the predicted ones and the models were highly significant, the correlation coefficient (R(2)) being 0.864, 0.663 and 0.776 for RB5, IC and AB, respectively. In addition, when the kinetic parameters for the three dyes decolourization were calculated according to Hannes-Wolf plot, the following values were obtained: Km of 268.4, 47.94 and 44.64 mg l(-1) then V(max) of 35.58, 10.43 and 9.23 mg l(-1) min for the RB5, IC and AB decolourizations by laccase, respectively. PMID:22659603

Daâssi, Dalel; Frikha, Fakher; Zouari-Mechichi, Hela; Belbahri, Lassaad; Woodward, Steve; Mechichi, Tahar

2012-10-15

287

Exploring the ability of Sphingobacterium sp. ATM to degrade textile dye Direct Blue GLL, mixture of dyes and textile effluent and production of polyhydroxyhexadecanoic acid using waste biomass generated after dye degradation  

Microsoft Academic Search

The degradation of textile effluent using microorganisms has been studied extensively, but disposal of generated biomass after dye degradation is a serious problem. Among all tested microorganisms, isolated Sphingobacterium sp. ATM effectively decolorized (100%) the dye Direct Blue GLL (DBGLL) and simultaneously it produced (64%) polyhydroxyhexadecanoic acid (PHD). The organism decolorized DBGLL at 300mgl?1 concentration within 24h of dye addition

Dhawal P. Tamboli; Mayur B. Kurade; Tatoba R. Waghmode; Swati M. Joshi; Sanjay P. Govindwar

2010-01-01

288

Calculation of the absorption wavelength of dyes using time-dependent density-functional theory (TD-DFT)  

Microsoft Academic Search

The absorption wavelengths and oscillator strengths of a series of organic dyes important for the dye industry (indigo, azobenzene, phenylamine, hydrazone, anthraquinone, naphthoquinone and cationic dyes) were calculated using time-dependent density-functional theory. The results were compared with experimental data. TD-DFT correctly reproduced the visible absorption of the dyes.

Dominique Guillaumont; Shinichiro Nakamura

2000-01-01

289

Potential Health Hazards of Organic Pigments and Dyes Used in the Manufacture of Paints and Surface Coatings. Appendix I: Scientific Basis for the Proposed Regulation of Dyes Derived from the Chemical Substances Benzidine, 3,3'-Dimethylbenzidine, and 3,3'-Dimethoxybenzidine,  

National Technical Information Service (NTIS)

The scientific bases for regulating dyes derived from benzidine (92875), 3,3'-dimethylbenzidine (119937), and 3,3'-dimethoxybenzidine (119904) are presented. Studies of these compounds have demonstrated that benzidine type dyes undergo nearly complete cle...

C. L. Jenkins

1978-01-01

290

Rational design of hyperbranched 3D heteroarrays of SrS/CdS: synthesis, characterization and evaluation of photocatalytic properties for efficient hydrogen generation and organic dye degradation  

NASA Astrophysics Data System (ADS)

Hyperbranched 3D SrS/CdS nanostructures were synthesized using a one pot hydrothermal method. Transmission Electron Microscopy (TEM) and Field Emission-Scanning Electron Microscopy (FE-SEM) analysis showed the formation of flower-like structure and the crystalline phase was confirmed by powder X-ray diffraction. The prepared 3D SrS/CdS exhibited improved photocatalytic activity for water splitting leading to H2 generation (AQY 10%) and nearly complete degradation of methyl orange (MO) dye. The dye degradation followed first order kinetics and the apparent reaction rate constant (kapp) was 0.136 min-1. The present 3D SrS/CdS structure promise to be efficient photocatalysts due to (i) the facile intersystem charge transfer resulting from their band alignment (ii) enhanced specific surface area and (iii) crystallinity.Hyperbranched 3D SrS/CdS nanostructures were synthesized using a one pot hydrothermal method. Transmission Electron Microscopy (TEM) and Field Emission-Scanning Electron Microscopy (FE-SEM) analysis showed the formation of flower-like structure and the crystalline phase was confirmed by powder X-ray diffraction. The prepared 3D SrS/CdS exhibited improved photocatalytic activity for water splitting leading to H2 generation (AQY 10%) and nearly complete degradation of methyl orange (MO) dye. The dye degradation followed first order kinetics and the apparent reaction rate constant (kapp) was 0.136 min-1. The present 3D SrS/CdS structure promise to be efficient photocatalysts due to (i) the facile intersystem charge transfer resulting from their band alignment (ii) enhanced specific surface area and (iii) crystallinity. Electronic supplementary information (ESI) available: Schematic experimental setup for photocatalytic hydrogen generation, TEM of CdS NWs and SrS NPs, FESEM images of 3D SrS/CdS, Low resolution TEM images for 3D SrS/CdS, EDX and SAED, SEM of SrS/CdS at different ratios, progress of hydrogen production at different time interval, different UV-Vis absorption spectra of MO. See DOI: 10.1039/c2nr30666b

Khan, Ziyauddin; Chetia, Tridip Ranjan; Qureshi, Mohammad

2012-05-01

291

Toxicity of Xanthene Food Dyes by Inhibition of Human Drug-Metabolizing Enzymes in a Noncompetitive Manner  

PubMed Central

The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC50 values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of 1O2 originating on xanthene dyes by light irradiation, because inhibition was prevented by 1O2 quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin.

Mizutani, Takaharu

2009-01-01

292

Peruvian natural dye plants  

Microsoft Academic Search

The use of natural dyes to color textiles and other objects has a long history in Andean South America, but has for the most\\u000a part become a lost technology with the introduction of synthetic dyes. A literature and field survey to recover information\\u000a about the traditional use of dye plants in Peru, from pre-Hispanic to recent times, was accompanied by

Kay K. Antúnez de Mayolo

1989-01-01

293

Ultrasonic assisted dyeing. IV. Dyeing of cationised cotton with lac natural dye  

Microsoft Academic Search

The dyeing of cationised cotton fabrics with lac natural dye has been studied using both conventional and ultrasonic techniques. The effects of dye bath pH, salt concentration, ultrasonic power, dyeing time and temperature were studied and the resulting shades obtained by dyeing with ultrasonic and conventional techniques were compared. Colour strength values obtained were found to be higher with ultrasonic

M. M. Kamel; Reda M. El-Shishtawy; B. M. Youssef; H. Mashaly

2007-01-01

294

Dyeing Wool with Fungi  

NSDL National Science Digital Library

In this activity (p.23 of PDF), learners dye wool with fungi. Learners discover that natural chemicals in fungi can dye wool different colors. Note: Natural dyeing normally requires a color fixative such as alum. This is not necessary if you use an aluminum, tin, or copper pot as the metal in the pot will take part in the dyeing reaction. However, if you use a non-stick saucepan you should add a few copper coins to the mix. Safety note: Always wash your hands after touching fungi! Adult supervision recommended.

Assinder, Sue; Rutter, Gordon

2002-01-01

295

Chemical Stabilization of Laser Dyes.  

National Technical Information Service (NTIS)

Coumarin laser dyes upon excitation degrade to produce products which absorb at the lasing wavelength. This results in attenuation of dye laser output. Modes of degradation of coumarin dye lasers under both anaerobic and aerobic conditions were determined...

T. H. Koch

1984-01-01

296

Quinoid conjugated dye designed for efficient sensitizer in dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

Paraquinoid rings are introduced in the ?-conjugation of all-organic donor-?-acceptor dyes as sensitizer in dye sensitized solar cells, to drastically shift optical response from violet-blue to near-infrared and to significantly enhance photoabsorption. Taking Y1 as a model, real time electron dynamics simulations based on time-dependent density functional theory confirm that paraquinoid conjugation maintains high thermal stability and ultrafast electron-hole separation at ambient temperature.

Jiao, Yang; Ma, Wei; Meng, Sheng

2013-10-01

297

Treatment of wastewater from dye manufacturing industry by coagulation  

Microsoft Academic Search

Chemical coagulation was used to remove the compounds present in wastewater from dye manufacturing industry. The character of wastewater was determined. Most compounds found in the wastewater are phenol derivatives, aniline derivatives, organic acid and benzene derivatives, output from dye manufacturing. Various polyferric chloride coagulants were investigated. Results showed that high extent of Fe(III) hydrolysis was not always suited for

YUAN Yu-li; WEN Yue-zhong; LI Xiao-ying; LUO Si-zhen

298

Association of heterogeneous dye molecules in microheterogeneous polymer micellar solutions  

NASA Astrophysics Data System (ADS)

Absorption spectra of a mixture of organic dyes in aqueous and micellar solutions of polyacrylic acid were investigated. Association processes in these microheterogeneous systems were studied. The degrees of homogeneous and heterogeneous association of dye mixtures were determined as functions of the polyelectrolyte concentration and its polyionic chain length and the influence on them of the polymer micellar complex structure.

Bulakov, D. V.; Ivanova, O. S.; Saletsky, A. M.

2013-07-01

299

Sorption and desorption of dyes by sulfonated coal  

Microsoft Academic Search

Wastewaters from dye-manufacturing factories and textile, paper, and pulp industries are highly colored. Their discharge into river waters make the water inhibitory to aquatic life, aside from causing, visible pollution. Dyes have a tendency to sequester metals, thus causing microtoxicity to fish and other aquatic organisms. A wide variety of low-cost materials such as flyash, clay minerals, coal, tire chippings,

A. K. Mittal; C. Venkobachar

2009-01-01

300

Kinetics of dye decolorization in an air–solid system  

Microsoft Academic Search

The photocatalytic decolorization of adsorbed organic dyes (Acid Blue 9, Acid Orange 7, Reactive Black 5 and Reactive Blue 19) in air was examined, applicable to self-cleaning surfaces and catalyst characterization. Dye-coated Degussa P25 titanium dioxide (TiO2) and dye-coated photo-inert aluminum oxide (Al2O3) particles, both of sub-monolayer initial dye coverage, were illuminated with 1.3mWcm?2 of near-UV light. Visual evidence of

Alison J. Julson; David F. Ollis

2006-01-01

301

Tris(2-(1H-pyrazol-1-yl)pyridine)cobalt(III) as p-type dopant for organic semiconductors and its application in highly efficient solid-state dye-sensitized solar cells.  

PubMed

Chemical doping is an important strategy to alter the charge-transport properties of both molecular and polymeric organic semiconductors that find widespread application in organic electronic devices. We report on the use of a new class of Co(III) complexes as p-type dopants for triarylamine-based hole conductors such as spiro-MeOTAD and their application in solid-state dye-sensitized solar cells (ssDSCs). We show that the proposed compounds fulfill the requirements for this application and that the discussed strategy is promising for tuning the conductivity of spiro-MeOTAD in ssDSCs, without having to rely on the commonly employed photo-doping. By using a recently developed high molar extinction coefficient organic D-?-A sensitizer and p-doped spiro-MeOTAD as hole conductor, we achieved a record power conversion efficiency of 7.2%, measured under standard solar conditions (AM1.5G, 100 mW cm(-2)). We expect these promising new dopants to find widespread applications in organic electronics in general and photovoltaics in particular. PMID:21972850

Burschka, Julian; Dualeh, Amalie; Kessler, Florian; Baranoff, Etienne; Cevey-Ha, Ngoc-Lê; Yi, Chenyi; Nazeeruddin, Mohammad K; Grätzel, Michael

2011-11-16

302

Effects of co-adsorbate and additive on the performance of dye-sensitized solar cells: A photophysical study  

Microsoft Academic Search

The effects of deoxycholic acid (DCA) in a dye solution as a co-adsorbate and guanidinium thiocyanate (GuSCN) in an electrolyte as an additive, on the photovoltaic performance of dye-sensitized solar cells (DSSCs) based on organic dye containing thiophene and fluorine segments (FL dye1) and black dye (BD) were investigated. The presence of DCA, up to 2mM, increases both the photovoltage

Kun-Mu Lee; Vembu Suryanarayanan; Kuo-Chuan Ho; K. R. Justin Thomas; Jiann T. Lin

2007-01-01

303

Importance of dye host on absorption, propagation losses, and amplified spontaneous emission for dye-doped polymer thin films  

Microsoft Academic Search

The absorption spectra of dye-doped polymer thin films made from a variety of five dyes and six matrices, either organic or organomineral, are analyzed to evaluate the residual absorption in the red wavelength tail and in particular at amplified spontaneous emission (ASE) wavelengths. An absorption cutoff wavelength is defined as the extrapolated wavelength at which the absorption losses are expected

Hélène Goudket; Tran Hong Nhung; Buntha Ea-Kim; Gisèle Roger; Michael Canva

2006-01-01

304

Perylene imide dyes for solid-state dye-sensitized solar cells: Spectroscopy, energy levels and photovoltaic performance  

Microsoft Academic Search

We report the solid-state dye-sensitized solar cell performances of perylene imide using nanoporous TiO2 electrodes. Solid-state dye-sensitized solar cells were fabricated using the organic hole-transporting medium (HTM) 2,2?7,7?-tetrakis-(N,N-di-p-methoxyphenyl-amine)-9,9?-spirobifluorene (spiro-OMeTAD). The experimental ELUMO levels of perylene imide dyes are found to be 3.75 and 3.77eV, respectively. Therefore, perylene imide dyes can inject electrons to the conduction band of titanium dioxide in

Sule Erten-Ela; Gulsah Turkmen

2011-01-01

305

Organic Dye-Doped Thin Films for Wavelength Conversion and Their Effects on the Photovoltaic Characteristics of CdS/CdTe Solar Cell  

NASA Astrophysics Data System (ADS)

For the improvement of the conversion efficiency of CdS/CdTe solar cells by applying the wavelength conversion properties, the spectroscopic studies of the fluorescent laser dye Rhodamine 6G (Rh6G)-doped into polyvinylbutyral (PVB) and polymethylmethacrylate (PMMA) were carried out. It was found that all the photoluminescence excitation (PLE) spectra below 540 nm were effectively converted to photoluminescence (PL) spectra in the wavelength region above 550 nm where the solar cell possessed a high spectral quantum efficiency. The external quantum efficiencies of PVB:Rh6G and PMMA:Rh6G films were estimated to be 0.9± 0.05 and 0.4± 0.1, respectively. When the PVB:Rh6G film was placed on the top of the CdS/CdTe solar cell, both short-circuit current and conversion efficiency increased by 11% compared with the cell with no film.

Hong, Byung-Chul; Kawano, Katsuyasu

2004-04-01

306

Low temperature preparation of ?-FeOOH/reduced graphene oxide and its catalytic activity for the photodegradation of an organic dye  

NASA Astrophysics Data System (ADS)

A new approach to prepare ?-FeOOH/reduced graphene oxide (RGO) at room temperature has been developed. Instead of reducing graphene oxide (GO) with the most commonly used reagents, which are highly toxic or explosive, Fe2+ was used as the reducing reagent. Fe2+ efficiently reduced GO under mild conditions to form ?-FeOOH/RGO via spontaneous in situ deposition of ?-FeOOH nanorods onto the RGO surfaces. The resulting ?-FeOOH/RGO was characterized by transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, x-ray photoelectron spectroscopy, x-ray diffraction analysis and infrared spectroscopy. The ?-FeOOH/RGO was then applied as a photocatalyst for the degradation of the azo dye, methyl orange.

Huang, Guanbo; Zhang, Congcong; Long, Ying; Wynn, Jeanne; Liu, Yu; Wang, Wei; Gao, Jianping

2013-10-01

307

Low temperature preparation of ?-FeOOH/reduced graphene oxide and its catalytic activity for the photodegradation of an organic dye.  

PubMed

A new approach to prepare ?-FeOOH/reduced graphene oxide (RGO) at room temperature has been developed. Instead of reducing graphene oxide (GO) with the most commonly used reagents, which are highly toxic or explosive, Fe²? was used as the reducing reagent. Fe²? efficiently reduced GO under mild conditions to form ?-FeOOH/RGO via spontaneous in situ deposition of ?-FeOOH nanorods onto the RGO surfaces. The resulting ?-FeOOH/RGO was characterized by transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, x-ray photoelectron spectroscopy, x-ray diffraction analysis and infrared spectroscopy. The ?-FeOOH/RGO was then applied as a photocatalyst for the degradation of the azo dye, methyl orange. PMID:24008350

Huang, Guanbo; Zhang, Congcong; Long, Ying; Wynn, Jeanne; Liu, Yu; Wang, Wei; Gao, Jianping

2013-10-01

308

Genome Sequence of Citrobacter sp. Strain A1, a Dye-Degrading Bacterium  

PubMed Central

Citrobacter sp. strain A1, isolated from a sewage oxidation pond, is a facultative aerobe and mesophilic dye-degrading bacterium. This organism degrades azo dyes efficiently via azo reduction and desulfonation, followed by the successive biotransformation of dye intermediates under an aerobic environment. Here we report the draft genome sequence of Citrobacter sp. A1.

Chan, Giek Far; Gan, Han Ming

2012-01-01

309

Oxazine laser dyes  

DOEpatents

New oxazine compounds useful as dye laser media in solution, are superiior to prior art materials. The oxazine dyes useful when pumped by the 578.2 nm copper line to operate in the 700-800 nm range are described by formula I ##STR1##

Hammond, Peter R. (Livermore, CA); Field, George F. (Danville, CA)

1992-01-01

310

[Berlin dye laser].  

PubMed

The conditions for an optimal ophthalmic coagulating system are derived from the absorption spectra of xanthophyll, melanin and hemoglobin. Coagulation is effected by a dye laser with two dyes. The continuously tunable range of 570 nm to 680 nm opens up new horizons in photocoagulation of the retina. PMID:6543236

Wollensak, J; Seiler, T

1984-12-01

311

Tie-Dye Chemistry  

NSDL National Science Digital Library

In their travels to the indigo dye pits of northern Nigeria, the authors were struck by the beauty, history, and chemistry of indigo dyeing. They returned from Nigeria eager to develop a laboratory exercise that would expose students to the science of ind

Cessna, Gretchen; Cessna, Stephen

2001-03-01

312

Anthracene solid polycyclic aromatic hydrocarbon whose derivatives possess antimicrobial activity. production dyes organic semiconductors. Anthracene exhibits new receptor selective recognition anions hydrogen bonding electrostatic interactions . Anthracene strong binding ACA- H2PO4- F- besides good anion recognition PET sensor fluoride detector acetate sensor.  

EPA Pesticide Factsheets

Did you mean: Anthracene solid polycyclic aromatic hydrocarbon whose derivatives possess antimicrobial activity. production dyes organic semiconductors. Anthracene exhibits new receptor selective recognition anions hydrogen bonding electrostatic interactions . Anthracene strong binding ACA- H2PO4- F- besides good anion recognition PET sensor fluoride detector acetate sensor. ?

313

Monolithic dye laser amplifier  

DOEpatents

A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

Kuklo, T.C.

1993-03-30

314

Monolithic dye laser amplifier  

DOEpatents

A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

Kuklo, Thomas C. (Ripon, CA)

1993-01-01

315

Evaluation of antibacterial, antifungal, and antioxidant properties of some food dyes  

Microsoft Academic Search

Natural dyes find use in the coloring of textiles, drugs, cosmetics, etc. Owing to their nontoxic effects, they are also used\\u000a for coloring various food products. In the present study antimicrobial properties of 8 food dyes against 10 bacteria and 5\\u000a fungal organisms were investigated. It was observed that red dyes showed best antibacterial activity while yellow dyes showed\\u000a better

Ramamoorthy Siva; Meera George Palackan; Lubaina Maimoon; T. Geetha; Dipita Bhakta; P. Balamurugan; S. Rajanarayanan

2011-01-01

316

TEXTILE DYES AND DYEING EQUIPMENT: CLASSIFICATION, PROPERTIES, AND ENVIRONMENTAL ASPECTS  

EPA Science Inventory

The report gives results of a study of available information on textile dyeing equipment, dyeing procedures, and dye chemistry, to serve as background data for estimating the properties and evaluating the associated risks of new commercial dyestuffs. It reports properties of dyes...

317

Dye system for dye laser applications  

DOEpatents

A dye of the DCM family, [2-methyl-6-[2-(1,2,3,4-tetrahydro-1-methyl-6-quinolinyl)ethenyl]-4H-pyran -4-ylidene]-propanedinitrile, dissolved in 2-phenoxyethanol, is non-mutagenic, stable and efficient, particularly in a pumped continuous wave laser system.

Hammond, Peter R. (Livermore, CA)

1991-01-01

318

Flexible solid-state dye solar cells  

Microsoft Academic Search

The cell structure concepts and materials to build solid-state dye solar cells based on nanocristalline titanium oxide and an organic hole conductor were investigated. The substrate cell is based on a metal foil and a semi-transparent gold window on top of the cell structure and the superstrate cell is deposited on ITO coated polymer foil replacing the traditional conductive glass

Toby B. Meyer; Andreas F. Meyer; Daniel Ginestoux

2002-01-01

319

Characteristics of dye-sensitized solar cells using natural dye  

Microsoft Academic Search

Dye-sensitized solar cells are expected to be used for future clean energy. Recently, most of the researchers in this field use Ruthenium complex as dye in the dye-sensitized solar cells. However, Ruthenium is a rare metal, so the cost of the Ruthenium complex is very high. In this paper, various dye-sensitized solar cells have been fabricated using natural dye, such

Shoji Furukawa; Hiroshi Iino; Tomohisa Iwamoto; Koudai Kukita; Shoji Yamauchi

2009-01-01

320

Percutaneous penetration of hair dyes  

Microsoft Academic Search

Scalp penetration of 7 hair dyes (oxidative and direct) that occurs under conditions of hair dye usage was evaluated for both rhesus monkey and man using 14C labeled materials by quantifying their absorbtion via urine assays. Both species showed a remarkably similar pattern of dye penetration. The extent of scalp penetratoon is slightly higher for direct dyes but in neither

L. J. Wolfram; H. I. Maibach

1985-01-01

321

Chemical stabilization of laser dyes  

NASA Astrophysics Data System (ADS)

Coumarin laser dyes upon excitation degrade to produce products which absorb at the lasing wavelength. This results in attenuation of dye laser output through interference of stimulated emission. The roles of singlet oxygen and excitation intensity on dye degradation were explored. Singlet oxygen is formed but its reactions with the dye do not appear to be a major cause of dye laser output deterioration. High light intensity results in dye sensitized, solvent oligomerization to yield materials which interfere with dye stimulated emission. 1, 4-Diazabicyclo2,2,2octane (DABCO)inhibits this oligomerization.

Koch, Tad H.

1987-05-01

322

Effect of nano-clay platelets on the J-aggregation of thiacyanine dye organized in Langmuir-Blodgett films: A spectroscopic investigation  

NASA Astrophysics Data System (ADS)

In this paper we report the effect of the incorporation of nano-dimensional clay platelets, laponite, on the J-aggregation of a thiacyanine dye N, N'-dioctadecyl thiacyanine perchlorate (NK) assembled into Langmuir-Blodgett (LB) monolayers. ?- A isotherms and atomic force microscopic studies confirm the successful incorporation of clay platelets into the Langmuir monolayer of NK. J-aggregates of NK remain present in LB films lifted at lower as well as higher surface pressures in the absence of laponite clay platelets. However, with the incorporation of clay platelets, J-aggregates are formed only in LB films lifted at higher surface pressure of 30 mN/m and totally absent in the films lifted at lower surface pressures of 10 and 15 mN/m. This may be due to the formation of nano-trapping level by overlapping of clay platelets at higher surface pressure. NK molecules may get squeezed to these nano-trapping to form J-aggregates.

Bhattacharjee, D.; Hussain, Syed Arshad; Chakraborty, S.; Schoonheydt, R. A.

2010-09-01

323

DFT study of the effect of different metals on structures and electronic spectra of some organic-metal compounds as sensitizing dyes  

NASA Astrophysics Data System (ADS)

Ruthenium polypyridined-derivative complexes are used in dye-sensitized solar cell [DSSC] as a light to current conversion sensitizer. In order to lower the cost of the DSSC the normal transition metals were used to replace the noble metal ruthenium, and some compounds [ML2L'] (M = Pt, Fe, Ni, Zn; L = isonicotinic acid, L' = maleonitriledithiolate, I = PtL2L', II = FeL2L', III = NiL2L', IV = ZnL2L') were selected as the replacement. The geometries, electronic structures and optical absorption spectra of these compounds have been studied by using density functional theory (DFT) calculation at the B3LYP/LANL2DZ, B3P86/LANL2DZ, B3LYP/GEN level of theory. All the geometric parameters are close to the experimental values. The HOMOs are mainly on the maleonitriledithiolate groups mixed with fewer characters of the metal atom, the LUMOs are mainly on the two pyridine ligands. This means that the electron transition is attributed to the LLCT. The maximum absorptions of complexes are found to be at 351 nm, 806 nm for compound I, and 542 nm for compound II. The maximum absorptions of complexes are found to be at 884 nm for compound III, and 560 nm for compound IV. This means that those compounds may be as a suitable sensitizer for solar energy conversion applications.

Tang, Guodong; Li, Rongqing; Kou, Shanshan; Tang, Tingling; Zhang, Yu; Wang, Yiwei

2014-02-01

324

Solvent effects on emission yield and lifetime for coumarin laser dyes. Requirements for a rotatory decay mechanism. Technical report, 1 January 1982-31 October 1982  

SciTech Connect

Photophysical parameters have been determined for coumarin laser dyes in organic solvents and water. Fluorescence yields and lifetimes were sensitive to solvent polarity depending on subtle features of dye structure. Protic solvents were important in reducing emission yield for certain dyes. Radiative and non-radiative rates were obtained and trends analyzed in terms of dye structure, solvent properties, and medium temperature.

Jones, G. II; Jackson, W.R.; Choi, C.; Bergmark, W.R.

1983-10-31

325

Anthraquinone Dye Toxicological Profiles.  

National Technical Information Service (NTIS)

The Consumer Product Safety Commission conducted a review of anthraquinone dyes having consumer application for which toxicity data was available. Both natural and synthetic anthraquinones have been employed as colorants in food, drugs, cosmetics, hair dy...

1981-01-01

326

Nanowire dye-sensitized solar cells  

Microsoft Academic Search

Excitonic solar cells-including organic, hybrid organic-inorganic and dye-sensitized cells (DSCs)-are promising devices for inexpensive, large-scale solar energy conversion. The DSC is currently the most efficient and stable excitonic photocell. Central to this device is a thick nanoparticle film that provides a large surface area for the adsorption of light-harvesting molecules. However, nanoparticle DSCs rely on trap-limited diffusion for electron transport,

Matt Law; Lori E. Greene; Justin C. Johnson; Richard Saykally; Peidong Yang

2005-01-01

327

Simultaneous determination of dyes in wines by HPLC coupled to quadrupole orbitrap mass spectrometry.  

PubMed

A new method combining the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with ultra high performance liquid chromatography and ESI quadrupole Orbitrap high-resolution MS was developed for the highly accurate and sensitive screening of 69 dyes in wines. Response surface methodology was employed to optimize the QuEChERS sample preparation method for the determination of 69 different analytes in wines for the first time. After optimization, the maximum predicted recovery was 99.48% rate for canacert indigo carmine under the optimized conditions of 10 mL acetonitrile, 1.45 g sodium acetate, 107 mg primary secondary amine, and 96 mg C18 . For the matrices studied, the recovery rates of the other 68 compounds ranged from 87.2-107.4%, with coefficient of variation < 6.4%. The mass accuracy typically obtained is routinely better than 1.6 ppm and only needed to be calibrated once a week. The LODs for the analytes are in the range 1-1000 ?g/kg. This method has been successfully applied on screening of dyes in commercial wines, and it is very useful for the fast screening of different food additives. PMID:24478185

Jia, Wei; Chu, Xiaogang; Ling, Yun; Huang, Junrong; Lin, Yuanhui; Chang, James

2014-04-01

328

Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique  

NASA Astrophysics Data System (ADS)

This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.

Abdel-Kareem, O.; Eltokhy, A.; Harith, M. A.

2011-09-01

329

Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique  

SciTech Connect

This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.

Abdel-Kareem, O. [Conservation Department, Faculty of Archaeology, Cairo University (Egypt); Eltokhy, A.; Harith, M. A. [National Institute of Laser Enhanced Science, Cairo University (Egypt)

2011-09-22

330

Optimization of a culture medium for ligninolytic enzyme production and synthetic dye decolorization using response surface methodology.  

PubMed

A Box-Wilson central composite design was applied to optimize copper, veratryl alcohol and l-asparagine concentrations for Trametes trogii (BAFC 212) ligninolytic enzyme production in submerged fermentation. Decolorization of different dyes (xylidine, malachite green, and anthraquinone blue) by the ligninolytic fluids from the cultures was compared. The addition of copper stimulated laccase and glyoxal oxidase production, but this response was influenced by the medium N-concentration, with improvement higher at low N-levels. The medium that supported the highest ligninolytic production (22.75 U/ml laccase, 0.34 U/ml manganese peroxidase, and 0.20 U/ml glyoxal oxidase) also showed the greatest ability to decolorize the dyes. Only glyoxal oxidase activity limited biodecoloration efficiency, suggesting the involvement of peroxidases in the process. The addition of 1-hydroxybenzotriazole (a known laccase mediator) to the ligninolytic fluids increased both their range and rate of decolorization. The cell-free supernatant did not decolorize xylidine, poly R-478, azure B, and malachite green as efficiently as the whole broth, but results were similar in the case of indigo carmine and remazol brilliant blue R. This indicates that the mycelial biomass may supply other intracellular or mycelial-bound enzymes, or factors necessary for the catalytic cycle of the enzymes. It also implies that this fungus implements different strategies to degrade dyes with diverse chemical structures. PMID:14648345

Trupkin, S; Levin, L; Forchiassin, F; Viale, A

2003-12-01

331

Microbial decolorization of azo dyes by Proteus mirabilis.  

PubMed

A bacterium identified as Proteus mirabilis was isolated from acclimated sludge from a dyeing wastewater treatment plant. This strain rapidly decolorized a deep red azo dye solution (RED RBN). Features of the decolorizing process related to biodegradation and biosorption were also studied. Although P. mirabilis displayed good growth in shake culture, color removal was best in anoxic static cultures. For color removal, the optimal pH and temperature were 6.5-7.5 and 30-35 degrees C, respectively. The organism exhibited a remarkable color removal capability, even at a high concentration of azo dye. More than 95% of azo dye was reduced within 20 h at a dye concentration of 1.0 g L-1. Decolorization appears to proceed primarily by enzymatic reduction associated with a minor portion, 13-17%, of biosorption to inactivated microbial cells. PMID:10455502

Chen, K C; Huang, W T; Wu, J Y; Houng, J Y

1999-07-01

332

Comparative performance evaluation of Aspergillus lentulus for dye removal through bioaccumulation and biosorption.  

PubMed

Dyes used in various industries are discharged into the environment and pose major environmental concern. In the present study, fungal isolate Aspergillus lentulus was utilized for the treatment of various dyes, dye mixtures and dye containing effluent in dual modes, bioaccumulation (employing growing biomass) and biosorption (employing pre-cultivated biomass). The effect of dye toxicity on the growth of the fungal isolate was studied through phase contrast and scanning electron microscopy. Dye biosorption was studied using first and second-order kinetic models. Effects of factors influencing adsorption and isotherm studies were also conducted. During bioaccumulation, good removal was obtained for anionic dyes (100 mg/l), viz. Acid Navy Blue, Fast Red A and Orange-HF dye (99.4 %, 98.8 % and 98.7 %, respectively) in 48 h. Cationic dyes (10 mg/l), viz. Rhodamine B and Methylene Blue, had low removal efficiency (80.3 % [48 h] and 92.7 % [144 h], respectively) as compared to anionic dyes. In addition to this, fungal isolate showed toxicity response towards Methylene Blue by producing larger aggregates of fungal pellets. To overcome the limitations of bioaccumulation, dye removal in biosorption mode was studied. In this mode, significant removal was observed for anionic (96.7-94.3 %) and cationic (35.4-90.9 %) dyes in 24 h. The removal of three anionic dyes and Rhodamine B followed first-order kinetic model whereas removal of Methylene Blue followed second-order kinetic model. Overall, fungal isolate could remove more than 90 % dye from different dye mixtures in bioaccumulation mode and more than 70 % dye in biosorption mode. Moreover, significant color removal from handmade paper unit effluent in bioaccumulation mode (86.4 %) as well as in biosorption mode (77.1 %) was obtained within 24 h. This study validates the potential of fungal isolate, A. lentulus, to be used as the primary organism for treating dye containing wastewater. PMID:22996821

Kaushik, Prachi; Malik, Anushree

2013-05-01

333

Influence of 12 MeV electron irradiation on the electrical and photovoltaic properties of Schottky type solar cell based on Carmine  

NASA Astrophysics Data System (ADS)

A Schottky diode with configuration Au/Carmine/p-Si/Al has been fabricated and it has been seen that the thin film on the p-Si substrate has exhibited a good rectifying behavior. The current-voltage ( I-V) characteristics of the device have been investigated in dark before electron irradiation and under white light illumination and after 12 MeV electron irradiation with fluency of 3×10 12 e -/cm 2. It has been seen that the device is sensitive to illumination and to electron irradiation. The barrier height value has decreased under illumination. The ideality factor and series resistance values have increased by 12 MeV electron irradiation. Furthermore, it has also seen that the reverse bias current and capacitance of the device have decreased after electron irradiation. This has been attributed to decrease in net ionized dopant concentration with electron irradiation.

Aydo?an, ?.; Türüt, A.

2011-08-01

334

The Comparative Nucleophilicity of Naphthoxide Derivatives in Reactions with a Fast-Red TR Dye: A Discovery-Oriented Capstone Project for the Second-Year Organic Laboratory  

ERIC Educational Resources Information Center

In this experiment, organic chemistry students perform reactions between three naphthyl acetate derivatives and the diazonium salt Fast-Red TR, under basic conditions. The three naphthyl acetate derivatives used in this study are 2-naphthyl acetate (1a), 6-bromo-2-naphthyl acetate (1b) and 1,6-dibromo-2-naphthyl acetate (1c). The two-step, one-pot…

Mascarenhas, Cheryl M.

2008-01-01

335

Capturing the Potential of Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells are a continually developing type of low-cost solar cells that have commercial efficiency around 6-10%. The proposed research here will be focusing on the photo-bleaching and improving techniques for electron transport. Nature has given us a goal to reach towards with proven techniques for converting light into energy with around 30-40% efficiency, however, chlorophyll, the light absorber in plants, is expensive and it is not practical to make solar cells with only chlorophyll as the absorber. One such alternative to chlorophyll is phthalocyanines which is a common industrial dye used in many applications. This dye has a common similar ring without the long phytol chain that chlorophyll has. Previous research has shown that encapsulating organic dyes can magnify the properties of dye from the increased concentration with a possible benefit of stabilizing the dye allowing it to slow down the photo bleaching significantly. Likewise, such encapsulation may help with thermal stability since many dye-sensitized solar cells require a liquid or gel solution that is sensitive to thermal expansion. Many researchers are also finding new ways to encapsulate the dyes or dope the p-n layers with nano and meso tubes to help with electron transport or build the p-n layers right in the tubes. This allows for countless layers and an overall more efficient design.

Benson, James

2010-10-01

336

Water soluble laser dyes  

DOEpatents

Novel water soluble dyes of the formula I are provided ##STR1## wherein R.sup.1 and R.sup.4 are alkyl of 1 to 4 carbon atoms or hydrogen; or R.sup.1 -R.sup.2 or R.sup.2 -R.sup.4 form part of aliphatic heterocyclic rings; R.sup.2 is hydrogen or joined with R.sup.1 or R.sup.4 as described above; R.sup.3 is --(CH.sub.2).sub.m --SO.sub.3.sup.-, where m is 1 to 6; X is N, CH or ##STR2## where Y is 2 --SO.sub.3.sup.- ; Z is 3, 4, 5 or 6 --SO.sub.3.sup.-. The novel dyes are particularly useful as the active media in water solution dye lasers.

Hammond, Peter R. (Livermore, CA); Feeman, James F. (Wyomissing, PA); Field, George F. (Santa Ana, CA)

1998-01-01

337

Efficiency and photostability of dye-doped solid-state lasers in different hosts  

Microsoft Academic Search

We survey the preparation procedures of pyrromethene (PM) and rhodamine dyes in silica, silica–zirconia, organically modified silicate (ormosil) and organic polymer matrices. Absorption and luminescence spectra, as well as decay time fluorescence of pyrromethene dyes are given. The solid-state laser samples were tested and their efficiencies and photostabilities at transversal pumping configuration, are given. Pyrromethene 597 had the best laser

Eli Yariv; Silke Schultheiss; Tsiala Saraidarov; Renata Reisfeld

2001-01-01

338

Dye filled security seal  

SciTech Connect

A security seal for providing an indication of unauthorized access to a sealed object includes an elongate member to be entwined in the object such that access is denied unless the member is removed. The elongate member has a hollow, pressurizable chamber extending throughout its length that is filled with a permanent dye under greater than atmospheric pressure. Attempts to cut the member and weld it together are revealed when dye flows through a rupture in the chamber wall and stains the outside surface of the member.

Wilson, Dennis C. W. (Tijeras, NM)

1982-04-27

339

Organic  

NSDL National Science Digital Library

Quiz questions from the organic chemistry question bank provide students with an excellent opportunity to review key concepts.. The Organic topic focuses on the basics of organic chemistry that are taught in general chemistry.

2007-12-07

340

Sonophotolytic degradation of azo dye reactive black 5 in an ultrasound/UV/ferric system and the roles of different organic ligands.  

PubMed

The sonophotolytic advance oxidation system (US/UV/Fe(3+)) could achieve synergistic degradation of reactive black 5 (RB5), as compared to UV/Fe(3+) and US/Fe(3+) systems. A synergy factor of 2.5 based on the pseudo-first-order degradation rate constant (k(obs)) was found, along with enhancements in organic detoxification and mineralization. The presence of organic ligands could affect the US/UV/Fe(3+) system differently. Oxalate, citrate, tartrate and succinate could enhance the RB5 degradation, while NTA and EDTA exhibited strong inhibitions. The influence of these ligands on k(obs)(RB5) in the US/UV/Fe(III)-ligand systems followed the sequence of oxalate > tartrate > succinate > citrate > without ligand > NTA > EDTA, while they could be degraded simultaneously with the k(obs)(ligand) order of oxalate > citrate > tartrate > succinate > NTA > EDTA. Monitoring of iron species and the generated H(2)O(2) and •OH revealed that the ligands in the US/UV/Fe(III)-ligand system could play different mechanistic roles: (1) promoting H(2)O(2) production, (2) accelerating Fenton reaction, and (3) competing with RB5 for reacting with •OH. Among the ligands, oxalate exhibited the most significant enhancement of RB5 oxidation in the sonophotolytic system, and the process was pH-dependent. An initial reaction lag in RB5 degradation was observed when Fe(2+) was used in lieu of Fe(3+) as the catalyst in the sonophotolytic system. PMID:21444101

Zhou, Tao; Lim, Teik-Thye; Wu, Xiaohui

2011-04-01

341

Treatment of wastewater from dye manufacturing industry by coagulation  

Microsoft Academic Search

Chemical coagulation was used to remove the compounds present in wastewater from dye manufacturing industry. The character\\u000a of wastewater was determined. Most compounds found in the wastewater are phenol derivatives, aniline derivatives, organic\\u000a acid and benzene derivatives, output from dye manufacturing. Various polyferric chloride coagulants were investigated. Results\\u000a showed that high extent of Fe(III) hydrolysis was not always suited for

Yu-li Yuan; Yue-zhong Wen; Xiao-ying Li; Si-zhen Luo

2006-01-01

342

Kinetic study of light-driven processes in photochromic dye-doped polymers used as gate insulators in photoswitchable organic field effect transistors  

NASA Astrophysics Data System (ADS)

The paper reports on kinetic measurements of coloring and bleaching reactions in the spiropyran - merocyanine photochromic system dissolved in poly(methyl methacrylate) matrix (PMMA/SP). The system was earlier used as the gate insulator in a photo-switchable organic field effect transistor (OFET), and the switching was attributed to the photochromic reaction taking place in the polymer matrix. The present measurements aimed at elucidating the mechanism of the switching by comparing the rate constants of the coloring and bleaching reactions with the rate constants of processes responsible for capacitance changes. The comparison of the rate constants seems to confirm the role of the photochromic process: to within experimental uncertainty the rate constants determined from the two methods are similar. Measurements of the temporal evolution of absorbance additionally reveal existence of an irreversible fatigue reaction, probably associated with admission of oxygen to some samples. The presence of oxygen is also responsible for a deterioration of performance of the OFETs under study.

Lutsyk, Petro; Janus, Krzysztof; Sworakowski, Juliusz; Kochalska, Anna; Nešp?rek, Stanislav

2012-08-01

343

Dye sensitization of single crystal semiconductor electrodes.  

PubMed

Even though investigations of dye-sensitized nanocrystalline semiconductors in solar cells has dominated research on dye-sensitized semiconductors over the past two decades, single crystal electrodes represent far simpler model systems for studying the sensitization process with a continuing train of studies dating back more than 40 years. Even today single crystal surfaces prove to be more controlled experimental models for the study of dye-sensitized semiconductors than the nanocrystalline substrates. This Account analyzes the scientific advances in the model sensitized single crystal systems that preceded the introduction of nanocrystalline semiconductor electrodes. It then follows the single crystal research to the present, illustrating both their striking simplicity of use and clarity of interpretation relative to nanocrystalline electrodes. Researchers have employed many electrochemical, photochemical, and scanning probe techniques for studying monolayer quantities of sensitizing dyes at specific crystallographic faces of different semiconductors. These methods include photochronocoulometry, electronic spectroscopy, and flash photolysis of dyes at potential-controlled semiconductor electrodes and the use of total internal reflection methods. In addition, we describe the preparation of surfaces of single crystal SnS(2) and TiO(2) electrodes to serve as reproducible model systems for charge separation at dye-sensitized solar cells. This process involves cleaving the SnS(2) electrodes and a photoelectrochemical surface treatment for TiO(2) that produces clean surfaces for sensitization (as verified by AFM) resulting in near unity yields for electron transfer from the molecular excited dyes into the conduction band. In recent experiments with ruthenium complexes at TiO(2) and with carboxylated cyanine dyes, we demonstrate the promise of this simple model for understanding dye-sensitized solar cells. In each of these systems, we can observe and analyze the complex photochemistry in a quantitative manner. Molecules of the well-known N3 ruthenium complex attach to four different crystallographic faces of anatase and rutile TiO(2) at different rates and to a different extent. With carboxylated cyanine dye sensitizers on these surfaces, molecular aggregation on the surface is a function of molecular structure and crystallographic face. In contrast with the N3 sensitizer these organic dyes undergo a photoinduced dimerization and desorption reaction when hydroquinone regenerators are present. With both classes of sensitizers, we demonstrate a new photochronocoulometric technique that quantifies the amount of attached dye on the electrode surface. We have completed initial experiments examining quantum dot sensitization of TiO(2) crystals, which could eventually lead to sensitizers with higher stability and absorption coefficients. Although these single crystal electrode models show promise for providing insights and predictive value in understanding the sensitization process, more sophisticated models will be needed to fully understand the charge transfer from the localized electronic states of the sensitizer to the extended states of the semiconductor. PMID:19924998

Spitler, Mark T; Parkinson, B A

2009-12-21

344

Infrared Dye Laser Study.  

National Technical Information Service (NTIS)

The feasibility of a flash lamp pumped, near infrared dye laser operating at a moderate repetition rate was shown. The laser produced output pulses of 17 kw peak power at a rate of 4 pulses per minute. The flow system that is essential for multiflash oper...

1973-01-01

345

Alzheimer's Dye Test?  

ERIC Educational Resources Information Center

Massachusetts Institute of Technology (MIT) scientists have developed a new dye that could offer noninvasive early diagnosis of Alzheimer's disease, a discovery that could aid in monitoring the progression of the disease and in studying the efficacy of new treatments to stop it. The work is published in Angewandte Chemie. Today, doctors can only…

Science Teacher, 2005

2005-01-01

346

Pyranoquinoline Laser Dyes.  

National Technical Information Service (NTIS)

The patent application pertains to 2-keto-6,7,8,9-tetrahydro-2H-pyrano(3,2-g)-quinoline and 2-keto-9-methyl-6,7,8,9-tetrahydro-2H-pyrano(3,2-g)-quinoline, compounds useful as laser dyes, which are prepared from 7-hydroxy-1,2,3,4-tetrahydroquinoline.

P. R. Hammond E. J. Schimitschek J. Trias

1976-01-01

347

Organization.  

ERIC Educational Resources Information Center

This theme issue on organization provides an annotated listing of Web sites, CD-ROMs and software, videos, books, and other resources related to organization to be used with K-8 students. Sidebars discuss being organized to be a good student, organizational identities, and organizing an election. Suggests student activities relating to…

Online-Offline, 1999

1999-01-01

348

Molecular sieves as host materials for supramolecular organization  

Microsoft Academic Search

The use of zeolites and mesoporous silicas (M41S family) as host materials for the supramolecular organization of organic dye molecules, metal sulfide clusters, and transition metal complexes is reviewed. For dye–zeolite systems, different stages of organization are discussed, ranging from the arrangement of the dyes in the zeolite channels to the specific adsorption of molecules at the channel entrances and

Dominik Brühwiler; Gion Calzaferri

2004-01-01

349

Photochemistry of coumarin laser dyes  

SciTech Connect

Coumarin laser dyes are widely used in dye lasers for the generation of tunable laser light in the blue-green spectral region. As in the case with most laser dyes, coumarin dyes undergo photochemical reactions that interfere with simulated emission and result in loss of laser power output. This thesis describes the photochemistry of coumarin laser dyes under both anaerobic and aerobic conditions and some attempts to extend the useful lifetime of several dyes in dye lasers. Irradiation of Coumarin 311, 7-dimethylamino-4-methyl-coumarin (15), in oxygen-free ethanol solution results in the inefficient dye destruction. Products formed absorb light at the lasing wavelength of the dye, interfere with stimulated emission, and decrease the power output of the dye laser. Addition of the sulfur free radical chain transfer agents ethanethiol and ethyl disulfide retard the rate of formation of photoproducts absorbing at the lasing wavelengths. Deuterium incorporation, from the irradiation of Coumarin 311 in the presence of ethanethiol-S-d and ethyl disulfide, indicates that photoproducts most likely result from the reactions of free radicals which are generated in a bimolecular reaction between excited Coumarin 311 and ground state Coumarin 311. Ethanethiol and ethyl disulfide are shown to decrease the rate of power loss from a Coumarin 1 (3) dye laser. The naturally occurring amino acid cysteine acts similarly.

von Trebra, R.J.

1984-01-01

350

Enhancement of the photoproperties of solid-state TiO2|dye|CuI cells by coupling of two dyes  

NASA Astrophysics Data System (ADS)

The electronic coupling of a natural pigment extracted from pomegranate fruits (rich with cyanin and exist as flavylium at natural PH) with an organic dye mercurochrome enhanced the performance of solid-state TiO2|dye|CuI-type photovoltaic cells sensitized from pomegranate pigments or mercurochrome individually.

Sirimanne, P. M.; Senevirathna, M. K. I.; Premalal, E. V. A.; Pitigala, P. K. D. D. P.

2006-06-01

351

The efficacies of common dyes in primary isolation media for recovery of pathogenic fungi.  

PubMed

Dyes incorporated into a basal medium of brain heart infusion, Sabhi, tryptic soy, or yeast extract--pepton--glucose (YxPG) agar for selective isolation of fungi were investigated. Dilutions of 1:500, 1:750, 1:1,000, 1:5,000, and 1:10,000 of 33 common dyes were tested against 11 gram-positive and 16 gram-negative bacteria. In addition, these dyes were tested against Cryptococcus neoformans, Candida albicans, and the dimorphic phases of Histoplasma capsulatum and Blastomyces dermatitidis. Twenty-one of the dyes did not inhibit any of the organisms tested. Brilliant green, gentian violet, and malachite green (at three dilutions) inhibited all the organisms tested. Methyl red was found to be the best dye in selecting for fungi. Several dyes were also found to inhibit selectively C. neoformans or C. albicans and the dimorphic fungi H. capsulatum or B. dermatitidis. PMID:389033

Brilliande, T W; Hollick, G E; Larsh, H W

1979-11-01

352

Optimization of staining conditions for microalgae with three lipophilic dyes to reduce precipitation and fluorescence variability.  

PubMed

When the fluorescence signal of a dye is being quantified, the staining protocol is an important factor in ensuring accuracy and reproducibility. Increasingly, lipophilic dyes are being used to quantify cellular lipids in microalgae. However, there is little discussion about the sensitivity of these dyes to staining conditions. To address this, microalgae were stained with either the lipophilic dyes often used for lipid quantification (Nile Red and BODIPY) or a lipophilic dye commonly used to stain neuronal cell membranes (DiO), and fluorescence was measured using flow cytometry. The concentration of the cells being stained was found not to affect the fluorescence. Conversely, the concentration of dye significantly affected the fluorescence intensity from either insufficient saturation of the cellular lipids or formation of dye precipitate. Precipitates of all three dyes were detected as events by flow cytometry and fluoresced at a similar intensity as the chlorophyll in the microalgae. Prevention of precipitate formation is, therefore, critical to ensure accurate fluorescence measurement with these dyes. It was also observed that the presence of organic solvents, such as acetone and dimethyl sulfoxide (DMSO), were not required to increase penetration of the dyes into cells and that the presence of these solvents resulted in increased cellular debris. Thus, staining conditions affected the fluorescence of all three lipophilic dyes, but Nile Red was found to have a stable fluorescence intensity that was unaffected by the broadest range of conditions and could be correlated to cellular lipid content. PMID:22648989

Cirulis, Judith T; Strasser, Bridget C; Scott, John A; Ross, Gregory M

2012-07-01

353

Multi-wavelength oscillation DFB solid-state dye laser with cascade-arranged gratings  

Microsoft Academic Search

Solid-state dye lasers have been developed as compact and easy-to-handle coherent light sources. In particular, distributed feedback (DFB) solid-state dye lasers are able to emit narrow-banded single-mode laser beams. In DFB lasers, the diffraction grating is a key device for selecting the laser oscillation wavelength from a fluorescent band of organic dye. We adopted an \\

N. Nakai; M. Fukuda

2007-01-01

354

Improvement of the efficiency of thiophene-bridged compounds for dye-sensitized solar cells  

Microsoft Academic Search

A quantum-chemical study is conducted in order to provide UV\\/Vis absorption spectra (with a ±0.20eV accuracy) and oxidation potentials (±0.50eV accuracy) of a series of conjugated metal-free organic dyes containing triphenylamine (TPA) and thiophene (TH) moieties. These compounds have recently been developed for dye sensitized solar cells (DSSCs), and are here compared to the tetrahydroquinoline (THQ) class of dyes. Our

Julien Preat; Denis Jacquemin; Catherine Michaux; Eric A. Perpète

2010-01-01

355

Painting With Natural Dyes  

NSDL National Science Digital Library

This activity is part of an integrated elementary unit called "Painted Tipis." The unit is best taught in the fall in conjunction with the September celebration "American Indian Heritage Week." It integrates lessons on literature through legends and myths, language (Blackfeet), and mathematics through structural components of the tipi. The activity introduces the students to the art of dyeing as used in ancestral tipi paintings. Historical cultural ties are an integral part of the Native American students learning and this unit provides those connections. The purpose of this lesson is to provide elementary students with the opportunity to explore, identify and locate area plants. The inquiry cooperative learning component of this lesson will be to determine the color (dye) producing possibilities of the plant. Students will also plan and carry out an experiment to produce the dyestuff of the plant as well as create possible mordants, which is a chemical or metallic compound that will "fasten" the color to the fabric.

Barbara Arrowtop (Heart Butte School)

1999-07-01

356

Dyeing of wool with natural anthraquinone dyes from Fusarium oxysporum  

Microsoft Academic Search

Two anthraquinone compounds are described which were produced by liquid cultures of Fusarium oxysporum (isolate no. 4), isolated from the roots of citrus trees affected with root rot disease. These anthraquinone compounds are 2-acetyl-3,8-dihydroxy-6-methoxy anthraquinone or 3-acetyl-2,8-dihydroxy-6-methoxy anthraquinone. Dyeing of wool fabrics with these new anthraquinone compounds as natural dyes has been studied. The values of dyeing rate constant, half-time

F. A. Nagia; R. S. R. EL-Mohamedy

2007-01-01

357

Dyeing fabrics with metals  

NASA Astrophysics Data System (ADS)

Traditionally, in textile dyeing, metals have been used as mordants or to improve the color produced by a natural or synthetic dye. In biomedical research and clinical diagnostics gold colloids are used as sensitive signals to detect the presence of pathogens. It has been observed that when metals are finely divided, a distinct color may result that is different from the color of the metal in bulk. For example, when gold is finely divided it may appear black, ruby or purple. This can be seen in biomedical research when gold colloids are reduced to micro-particles. Bright color signals are produced by few nanometer-sized particles. Dr. William Todd, a researcher in the Department of Veterinary Science at the Louisiana State University, developed a method of dyeing fabrics with metals. By using a reagent to bond the metal particles deep into the textile fibers and actually making the metal a part of the chemistry of the fiber. The chemicals of the fabric influence the resulting color. The combination of the element itself, the size of the particle, the chemical nature of the particle and the interaction of the metal with the chemistry of the fabric determine the actual hue. By using different elements, reagents, textiles and solvents a broad range of reproducible colors and tones can be created. Metals can also be combined into alloys, which will produce a variety of colors. The students of the ISCC chapter at the Fashion Institute of Technology dyed fabric using Dr. Todd's method and created a presentation of the results. They also did a demonstration of dyeing fabrics with metals.

Kalivas, Georgia

2002-06-01

358

Dye laser tuner  

SciTech Connect

A laser of the kind in which the lasing medium is a free flowing dye stream incorporates a means of tuning the output wave length of the laser, this means being in the form of a wedged birefringent plate which is driven in a linear mode by a linear translator so that the thickness of the birefringent plate traversed by the intracavity beam of laser light may be varied.

Arthurs, E.G.; Purdie, A.F.

1980-11-11

359

Sonochemical degradation of martius yellow dye in aqueous solution.  

PubMed

The sonolytic degradation of the textile dye martius yellow, also known as either naphthol yellow or acid orange 24, was studied at various initial concentrations in water. The degradation of the dye followed first-order kinetics under the conditions examined. Based on gas chromatographic results and sonoluminescence measurements of sonicated aqueous solutions of the dye, it is concluded that pyrolysis does not play a significant role in its degradation. The chromatographic identification of hydroxy added species indicates that an OH radical induced reaction is the main degradation pathway of the dye. Considering the non-volatility and surface activity of the dye, the degradation of the dye most probably takes place at the bubble/solution interface. The quantitative and qualitative formation of the degradation intermediates and final products were monitored using HPLC and ESMS. The analytical results suggest that the sonolytic degradation of the dye proceeds via hydroxylation of the aryl ring and also by C-N bond cleavage of the chromophoric ring, either through OH radical attack or through another unidentified process. The identification of various intermediates and end products also imply that the degradation of martius yellow proceeds through multiple reaction pathways. Total organic carbon (TOC) analyses of the dye solutions at various times following sonication revealed that sonolysis was effective in the initial degradation of the parent dye but very slow in achieving mineralization. The slow rate of mineralization is likely to be due to the inability of many of the intermediate products such as, the carboxylic acids, to accumulate at the bubble (air/water) interface and undergo decomposition due to their high water solubility (low surface activity). PMID:18603462

Singla, Ritu; Grieser, Franz; Ashokkumar, Muthupandian

2009-01-01

360

Cold Pad-Batch dyeing method for cotton fabric dyeing with reactive dyes using ultrasonic energy.  

PubMed

Reactive dyes are vastly used in dyeing and printing of cotton fibre. These dyes have a distinctive reactive nature due to active groups which form covalent bonds with -OH groups of cotton through substitution and/or addition mechanism. Among many methods used for dyeing cotton with reactive dyes, the Cold Pad Batch (CPB) method is relatively more environment friendly due to high dye fixation and non requirement of thermal energy. The dyed fabric production rate is low due to requirement of at least twelve hours batching time for dye fixation. The proposed CPB method for dyeing cotton involves ultrasonic energy resulting into a one third decrease in batching time. The dyeing of cotton fibre was carried out with CI reactive red 195 and CI reactive black 5 by conventional and ultrasonic (US) method. The study showed that the use of ultrasonic energy not only shortens the batching time but the alkalis concentrations can considerably be reduced. In this case, the colour strength (K/S) and dye fixation (%F) also enhances without any adverse effect on colour fastness of the dyed fabric. The appearance of dyed fibre surface using scanning electron microscope (SEM) showed relative straightening of fibre convolutions and significant swelling of the fibre upon ultrasonic application. The total colour difference values ?E (CMC) for the proposed method, were found within close proximity to the conventionally dyed sample. PMID:21550289

Khatri, Zeeshan; Memon, Muhammad Hanif; Khatri, Awais; Tanwari, Anwaruddin

2011-11-01

361

Dye-coated europium monosulfide  

SciTech Connect

Nanoparticles of EuS were synthesized using europium dithiocarbamate complexes. The resulting nanoparticles were coated with the dye, 1-pyrene carboxylic acid and the resulting material was characterized using X-ray powder diffraction, TEM, and UV-visible spectroscopy. Fluorescence spectroscopy was used to determine the relative energy of the conduction band edge to the excited state energy of the dye. -- Graphical abstract: Dye sensitized magnetic semiconductor materials were prepared by synthesizing EuS nanoparticles using single source precursors and coating with the dye, 1-pyrene carboxylic acid. Display Omitted highlights: > Synthesized EuS nanoparticles, 11{+-}2.4 nm characterized using XRD, TEM, and UV-vis. spect. > Grafted a dye to the surface and characterized the product using XRD, FTIR, UV-vis., and TEM. > Studied the photophysical properties using fluorescence spectroscopy. > Determined the relative dye excited state to the conduction band of the semiconductor.

Kar, Srotoswini [Department of Chemistry, Georgetown University, Washington D.C. 20057 (United States); Dollahon, Norman R. [Department of Biology, Villanova University, Villanova, PA 19085 (United States); Stoll, Sarah L., E-mail: sls55@georgetown.ed [Department of Chemistry, Georgetown University, Washington D.C. 20057 (United States)

2011-05-15

362

Study of a natural dye solubilisation in o\\/w microemulsions and its dyeing behaviour  

Microsoft Academic Search

The manufacture of synthetic dyes involves many non eco-friendly chemical procedures. For this reason, the application of natural dyes in textile dyeing is being explored worldwide. The dye exhaustion, fixation and levelness of dyeing depends on several factors such as the properties of fibres, the molecular structure of dyes, and the medium of the dyebath. The solubilisation of insoluble natural

Roshan Paul; Conxita Solans; Pilar Erra

2005-01-01

363

Multiwalled carbon nanotubes dispersed in carminic acid for the development of catalase based biosensor for selective amperometric determination of H(2)O(2) and iodate.  

PubMed

We report the preparation of stable dispersion of multiwalled carbon nanotubes (MWCNTs) using carminic acid (CA) as a dispersing agent. The transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) results confirmed that MWCNT is well dispersed in CA aqueous solution and CA has been well adsorbed at MWCNT walls. Fourier transform infrared (FTIR) and UV-vis absorption spectra results also confirmed the adsorption of CA at MWCNT. To develop a highly selective amperometric biosensor for H(2)O(2) and iodate, the model enzyme catalase (CAT) was immobilized at CACNT modified glassy carbon electrode surface. The immobilized CAT exhibits well defined quasi reversible redox peaks at a formal potential (E°') of -0.559V in 0.05M pH 7 phosphate buffer solution (PBS). The proposed CAT/CACNT biosensor exhibits excellent amperometric response towards H(2)O(2) and iodate in the linear concentration range between 10?M to 3.2mM and 0.01-2.16mM. The sensitivity values are 287.98?AmM(-1)cm(-2) and 0.253mAmM(-1)cm(-2), respectively. Moreover, the developed CAT biosensor exhibits high affinity for H(2)O(2) and iodate with good selectivity. PMID:21900003

Periasamy, Arun Prakash; Ho, Ya-Hui; Chen, Shen-Ming

2011-11-15

364

Investigation of red natural dyes used in historical objects by HPLC-DAD-MS.  

PubMed

High performance liquid chromatography (HPLC) with UV-Vis Diode Array Detection (DAD) and electrospray mass spectrometric (ESI-MS) method was utilized for the identification of coloring components of madder, Armenian and Mexican cochineal, lac dye, brazilwood, safflower and dragon blood--probably the most important red natural dyestuffs found in objects of the cultural heritage. UV-Vis detection limits in the range of 0.2-0.6 ng for carminic acid, alizarin and purpurin were achieved using a gradient elution of H2O-0.01% TFA and CH3CN-0.01% TFA. ESI mass spectrometer was also used, as a supportive detection method to the standard DAD, for further analysis of the tested materials, with the ability to analyze dyestuffs as small as one milligram. The presence of madder was revealed in two historical (Hellenistic and Roman period) samples, found in the Mediterranean area, by identifying purpurin in both of them. Munjistin was also identified in one of the samples (Hellenistic period) while alizarin was not detected, raising questions regarding the exact madder type, utilized in the historical samples. PMID:16736555

Karapanagiotis, Ioannis; Chryssoulakis, Yannis

2006-01-01

365

Grape stalks as substrate for white rot fungi, lignocellulolytic enzyme production and dye decolorization.  

PubMed

The aim of this work was to evaluate the potential of grape stalks, an agroindustrial waste, for growth and lignocellulolytic enzyme production via solid-state fermentation, using the following three white rot fungi: Trametes trogii, Stereum hirsutum and Coriolus antarcticus. The decolorization of several dyes by the above mentioned cultures was also investigated. Similar values of dry weight loss of the substrate were measured after 60 days (33-43 %). C. antarcticus produced the highest laccase and Mn-peroxidase activities (33.0 and 1.6 U/g dry solid). The maximum endoglucanase production was measured in S. hirsutum cultures (10.4 U/g), while the endoxylanase peak corresponded to T. trogii (14.6 U/g). The C. antarcticus/grape stalk system seems potentially competitive in bioremediation of textile processing effluents, attaining percentages of decolorization of 93, 86, 82, 82, 77, and 58% for indigo carmine, malachite green, azure B, remazol brilliant blue R, crystal violet and xylidine, respectively, in 5 h. PMID:22997770

Levin, Laura; Diorio, Luis; Grassi, Emanuel; Forchiassin, Flavia

2012-01-01

366

Fine Tuning of Fluorene-Based Dye Structures for High-Efficiency p-Type Dye-Sensitized Solar Cells.  

PubMed

We report on an experimental study of three organic push-pull dyes (coded as zzx-op1, zzx-op1-2, and zzx-op1-3) featuring one, two, and three fluorene units as spacers between donors and acceptors for p-type dye-sensitized solar cells (p-DSSC). The results show increasing the number of spacer units leads to obvious increases of the absorption intensity between 300 nm and 420 nm, a subtle increase in hole driving force, and almost the same hole injection rate from dyes to NiO nanoparticles. Under optimized conditions, the zzx-op1-2 dye with two fluorene spacer units outperforms other two dyes in p-DSSC. It exhibits an unprecedented photocurrent density of 7.57 mA cm(-2) under full sun illumination (simulated AM 1.5G light illumination, 100 mW cm(-2)) when the I(-)/I3(-) redox couple and commercial NiO nanoparticles were used as an electrolyte and a semiconductor, respectively. The cells exhibited excellent long-term stability. Theoretical calculations, impedance spectroscopy, and transient photovoltage decay measurements reveal that the zzx-op1-2 exhibits lower photocurrent losses, longer hole lifetime, and higher photogenerated hole density than zzx-op1 and zzx-op1-3. A dye packing model was proposed to reveal the impact of dye aggregation on the overall photovoltaic performance. Our results suggest that the structural engineering of organic dyes is important to enhance the photovoltaic performance of p-DSSC. PMID:24918263

Liu, Zonghao; Li, Wenhui; Topa, Sanjida; Xu, Xiaobao; Zeng, Xianwei; Zhao, Zhixin; Wang, Mingkui; Chen, Wei; Wang, Feng; Cheng, Yi-Bing; He, Hongshan

2014-07-01

367

Synthesis and application of H-Bonded cross-linking polymers containing a conjugated pyridyl H-Acceptor side-chain polymer and various carbazole-based H-Donor dyes bearing symmetrical cyanoacrylic acids for organic solar cells  

Microsoft Academic Search

A series of novel hydrogen-bonded (H-bonded) cross-linking polymers were generated by complexing various proton-donor (H-donor) solar cell dyes containing 3,6- and 2,7-functionalized electron-donating carbazole cores bearing symmetrical thiophene linkers and cyanoacrylic acid termini with a proton-acceptor (H-acceptor) side-chain homopolymer carrying pyridyl pendants (with 1\\/2 M ratio of H-donor\\/H-acceptor). The supramolecular H-bonded structures between H-donor dyes and the H-acceptor side-chain polymer were

Duryodhan Sahu; Harihara Padhy; Dhananjaya Patra; Dhananjay Kekuda; Chih-Wei Chu; I.-Hung Chiang; Hong-Cheu Lin

2010-01-01

368

Harmonic generation in organic dye vapors  

Microsoft Academic Search

Investigations of nonlinear optical frequency conversion of Nd:YAG laser radiation in naphthalene vapors are presented. The third harmonic generation (THG) caused by difference frequency generation in six-photon process has been studied. Phase-matching temperature for naphthalene vapor was found to be 170°C, at which synchronous conversion of pump radiation to the third harmonic was carried out. The THG conversion efficiency varied

R. A. Ganeev; Sh. R. Kamalov; M. K. Kodirov; M. R. Malikov; A. I. Ryasnyansky; R. I. Tugushev; Sh. U. Umidullaev; T. Usmanov

2000-01-01

369

The Chemistry of Plant and Animal Dyes.  

ERIC Educational Resources Information Center

Provides a brief history of natural dyes. Chemical formulas are provided for flavonoids, luteolin, genistein, brazilin, tannins, terpenes, naphthoquinone, anthraquinone, and dyes with an alkaloid structure. Also discusses chemical background of different dye processes. (CS)

Sequin-Frey, Margareta

1981-01-01

370

Organics.  

ERIC Educational Resources Information Center

Presents water analysis literature for 1978. This review is concerned with organics, and it covers: (1) detergents and surfactants; (2) aliphatic and aromatic hydrocarbons; (3) pesticides and chlorinated hydrocarbons; and (4) naturally occurring organics. A list of 208 references is also presented. (HM)

Chian, Edward S. K.; DeWalle, Foppe B.

1978-01-01

371

Identification of Red Natural Dyes in Post?Byzantine Icons by HPLC  

Microsoft Academic Search

A high performance liquid chromatography (HPLC) methodology, combined with UV?Vis Diode Array Detection, is developed for the separation and identification of five reddish natural dyestuffs: cochineal, madder, lac dye, dragon blood, and brazilwood. The method is used for the identification of organic dyes in extracts originating from five icons, four of which are representative for the post Byzantine era (15th

Ioannis Karapanagiotis; sist. Daniilia; Andreas Tsakalof; Yannis Chryssoulakis

2005-01-01

372

Removal of textile dyes from aqueous solutions by natural phosphate as a new adsorbent  

Microsoft Academic Search

The objective of this study was to investigate the ability of natural phosphate (NP) to remove textile dyes from aqueous solutions. The adsorption of methylene blue (MB) as a reference molecule for the adsorption studies of organic molecules, basic yellow 28 (BY 28) and reactive yellow 125 (RY 125) representatives of two families of textile dyes was studied in a

Noureddine Barka; Ali Assabbane; Abederrahman Nounah; Larbi Laanab; Yhya Aît Ichou

2009-01-01

373

Performance and dye-degrading bacteria isolation of a hybrid membrane process  

Microsoft Academic Search

Textile dyeing wastewater contains harmful compounds, which are toxic to both marine organisms and human beings if it discharged into an aquatic environmental without suitable treatment. In this study, the wastewater containing the azo dye, Reactive Black 5 (RB5), was partially treated in an anaerobic sequencing batch reactor which was further treated either in an aerobic membrane bioreactors (AOMBR) or

Sheng-Jie You; Jun-Yu Teng

2009-01-01

374

Synthesis and light emitting properties of polymeric metal complex dyes based on hydroxyquinoline moiety  

Microsoft Academic Search

Two kinds of polymeric metal complex dyes, Al(PHQ) 6 and Zn(PHQ) 7, have been prepared. New polymeric dyes were examined as an light emitting material in organic EL devices. The forward bias turn-on voltage for the EL devices is 8 V for Al(PHQ) 6.

Sung-Hoon Kim; Jian-Zhong Cui; Jin-Yong Park; Jang-Hyun Ryu; Eun-Mi Han; Su-Mi Park; Sung-Ho Jin; Kwangnak Koh; Yeong-Soon Gal

2002-01-01

375

FM-dyes as experimental probes for dissecting vesicle trafficking in living plant cells  

Microsoft Academic Search

Summary FM-dyes are widely used to study endocytosis, vesicle traffick- ing and organelle organization in living eukaryotic cells. The increasing use of FM-dyes in plant cells has provoked much debate with regard to their suitability as endocytosis markers, which organelles they stain and the precise pathways they follow through the vesicle trafficking network. A primary aim of this article is

S. Bolte; C. Talbot; Y. Boutte; O. Catrice; N. D. Read; B. Satiat-Jeunemaitre

2004-01-01

376

Biodegradability oriented treatability studies on high strength segregated wastewater of a woolen textile dyeing plant  

Microsoft Academic Search

Textile dyeing and finishing industry involves considerable amount of water usage as well as polluted and highly colored wastewater discharges. Biological treatability by means of mineralization, nitrification and denitrification of high strength woolen textile dye bathes, first- and second-rinses is presented. COD fractionation study was carried out and kinetic parameters were determined. Biodegradability of organic compounds in highly loaded composite

Ahmet Baban; Ayfer Yediler; NilgunKiran Ciliz; Antonius Kettrup

2004-01-01

377

Electrochemical oxidation of a textile dye wastewater using a Pt\\/Ti electrode  

Microsoft Academic Search

Textile dye wastewater (TDW) from a reactive azo dyeing process was treated by an electrochemical oxidation method using Ti\\/Pt as anode and stainless steel 304 as cathode. Due to the strong oxidizing potential of the chemicals produced (chlorine, oxygen, hydroxyl radicals and other oxidants) when the wastewater was passed through the electrolytic cell the organic pollutants were oxidized to carbon

A. G Vlyssides; M Loizidou; P. K Karlis; A. A Zorpas; D Papaioannou

1999-01-01

378

Decolorization and Detoxification of Textile Dyes with a Laccase from Trametes hirsuta  

Microsoft Academic Search

Trametes hirsuta and a purified laccase from this organism were able to degrade triarylmethane, indigoid, azo, and anthraquinonic dyes. Initial decolorization velocities depended on the substituents on the phenolic rings of the dyes. Immobilization of the T. hirsuta laccase on alumina enhanced the thermal stabilities of the enzyme and its tolerance against some enzyme inhibitors, such as halides, copper chelators,

ELIAS ABADULLA; TZANKO TZANOV; SILGIA COSTA; KARL-HEINZ ROBRA; ARTUR CAVACO-PAULO; GEORG M. GUBITZ

2000-01-01

379

Polymeric dyes based on thiadiazole derivatives  

Microsoft Academic Search

A series of polymeric dyes were synthesized by free radical addition polymerization of monomeric dyes. The 2-amino-5-mercapto-1,3,4-thiadiazole\\u000a was diazotized and coupled with various N-arylmaleimides to give monomeric dyes. All the polymeric dyes were characterized\\u000a by elemental analysis, infrared spectroscopy, visible absorption spectroscopy, viscometry, and thermogravimetric analysis.\\u000a Color and dyeing properties of the polymeric dyes were discussed by comparing them with

Hari Raghav Maradiya; Vithal Soma Patel

2001-01-01

380

Coloring and habit modification of dyed KDP crystals as functions of supersaturation and dye concentration  

NASA Astrophysics Data System (ADS)

Azo-organic dyes as additives were examined to make colored KDP (potassium dihydrogen phosphate) crystals. The dyes used here were amaranth and sunset-yellow FCF. Influences of supersaturation and dye concentration in the solution were observed on the color and crystal habit of KDP. Amaranth colored the pyramidal section (1 0 1) of the crystals in the solution at low supersaturation and high dye concentration. The highly supersaturated solutions produced entirely colored crystals. The crystal habit did not significantly change in the amaranth solution. Sunset-yellow FCF had a significant effect on the crystal habit and color of KDP, and the prismatic section of the crystals was decreased. Sunset-yellow FCF colored the whole KDP crystals in the solution at high dye concentration. The habit index of KDP crystal, which is the ratio of the pyramidal size to prismatic size, was discussed as a function of dye concentration and supersaturation.

Hirota, Shouji; Miki, Hideo; Fukui, Keisuke; Maeda, Kouji

2002-02-01

381

Utilization of carbon nanotubes for the removal of rhodamine B dye from aqueous solutions.  

PubMed

Carbon nanotubes (CNTs) are attracting increasing research interest as promising adsorbents for harmful cations, anions, and other organic and inorganic impurities present in natural sources of water. This study examined the feasibility of removing Rhodamine B dye from aqueous solutions using multi walled carbon nanotubes (MWCNTs) synthesized by chemical vapor deposition (CVD) method. The effects of dye concentration, pH and contact time on adsorption of direct dye by CNTs were also evaluated. The study used the Langmuir and Temkin isotherms to describe equilibrium adsorption. Additionally, pseudo second-order model was adopted to evaluate experimental data and thereby elucidate the kinetic adsorption process. The adsorption percentage of dye increased as contact time increased. Conversely, the adsorption percentage of dye decreased as dye concentration increased. The pseudo second-order model best represented adsorption kinetics. The capacity of CNTs to adsorb Rhodamine B was 65-90% at different pH values. PMID:24738392

Kumar, Sandeep; Bhanjana, Gaurav; Jangra, Kavita; Dilbaghi, Neeraj; Umar, Ahmad

2014-06-01

382

Spectroscopic and photoelectrochemical studies of metal-free dyes for applications in dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

In this dissertation, we present a series of novel chalcogenorhodamine dyes bearing phosphonic acids and carboxylic acids for sensitizers of nanocrystalline TiO2 in dye-sensitized solar cells (DSCs). We studied the effect of surface-attachment functionality and aggregation on the persistence, electron transfer reactivity, and overall photoelectrochemical performance of the dyes on TiO2 for DSCs. 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), 2-carboxythien-3-yl in dyes 2-E (E = Se), 5-phosphonothien-2-yl in dyes 3-E (E = O, Se), 4-carboxyphenyl in dyes 4-E (E = O, S), and 4-phosphonophenyl in dyes 5-E (E = O, Se). Monolayers of 1-E, 3-E, 4-E, and 5-E on nanocrystalline TiO2 films consisted of both H-aggregated and non-aggregated dyes, whereas 2-E underwent little or no aggregation upon adsorption. With the exception of 2-E, surface coverages of dyes and the extent of H-aggregation varied minimally with surface-attachment functionality, structure of the 9-aryl group, and identity of the chalcogen heteroatom. Carboxylic acid-functionalized dyes 1-E and 4-E desorbed rapidly and completely from TiO2 into acidified CH3CN, but phosphonic acid-functionalized dyes 3-E and 5-E persisted on TiO2 for days. We used transient absorption spectroscopy to characterize excited-state electron injection from a 1-Se, 2-Se, and 3-Se to TiO2. Injection of electrons from photoexcited dyes into TiO2 yielded the dication radical (1-Se +, 2-Se+, and 3-Se +) and an associated transient absorption at wavelengths shorter than 540 nm, the amplitude of which was proportional to the quantum yield of electron injection (Qinj). Our data reveal the Qinj for H-aggregated 1-Se was approximately 2-fold greater than Q inj for non-aggregated 1-Se and approximately 3-fold greater than Qinj for non-aggregated 2-Se. Additionally, the Qinj from H-aggregated 3-Se was (2.0 +/- 1.3)-fold greater than from monomeric 3-Se. Therefore, H-aggregation increased the efficiencies of both light-harvesting and electron injection. Comparison of the analogous carboxylic acid-functionalized dye (1-Se) and phosphonic acid-functionalized dye (3-Se) revealed that Q inj via the carboxylate linkage was (2.3 +/- 1.1)-fold greater than via the phosphonate linkage. Thus, electron-injection reactivity is sensitive to both the aggregation state and the surface-anchoring mode of these chalcogenorhodamine dyes. Short-circuit photocurrent action spectra of DSCs corresponded closely to 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 DSCs ranged from 53% to 95% and were slightly higher for carboxylic acid-functionalized dyes 1-E and 4-E. The photoelectrochemical performance (under monochromatic or white-light illumination) of 1-E and 4-E decayed significantly within 20-80 min of assembly of DSCs, due primarily to desorption of the dyes. In contrast, the performance of phosphonic acid-functionalized dyes (3-E and 5-E) remained stable or improved slightly on similar time scales. Power-conversion efficiencies of DSCs under white-light illumination were low (<1%), suggesting that dye regeneration was inefficient at high light intensities. Preliminary transient photovoltage results support this proposition. Our findings suggest that controlled aggregation of organic dyes may represent an attractive strategy for improving the global energy-conversion efficiencies of organic dye-sensitized solar cells and photocatalysts. In addition, replacing carboxylic acids with phosphonic acids increased the inertness of chalcogenorhodamine-TiO2 interfaces without greatly impacting aggregation of dyes or the interfacial electron-transfer reactivity. The decrease of Qinj for phosphonic acid-bearing dyes is offset by its enhanced stability and persistence on TiO2, rendering the phosphonic acid-functionalized and H-aggregating dyes

Mulhern, Kacie Ryan

383

Gel Electrophoresis of Dyes  

NSDL National Science Digital Library

In this experiment related to plant biotechnology, learners discover how to prepare and load an electrophoresis gel. They will then run the gels in an electrophoresis system to separate several dyes that are of different molecular sizes and carry different charges. This technique is fundamental to many of the procedures used in biotechnology. This lesson guide includes background information for the educator, safety precautions, and questions with answers for learners. For safety reasons, adult supervision is recommended. Modifications for use with younger learners are described in a related PDF (see related resource).

Stephens, Janice; Leach, Jan

2011-01-01

384

Dye Sensitized Solar Cells  

PubMed Central

Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

Wei, Di

2010-01-01

385

Dye sensitized solar cells.  

PubMed

Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed. PMID:20480003

Wei, Di

2010-01-01

386

Ultrasound for low temperature dyeing of wool with acid dye.  

PubMed

The possibility of reducing the temperature of conventional wool dyeing with an acid levelling dye using ultrasound was studied in order to reach exhaustion values comparable to those obtained with the standard procedure at 98 °C, obtaining dyed samples of good quality. The aim was to develop a laboratory method that could be transferred at industrial level, reducing both the energy consumption and fiber damage caused by the prolonged exposure to high temperature without the use of polluting auxiliary agents. Dyeings of wool fabrics were carried out in the temperature range between 60 °C and 80 °C using either mechanical or ultrasound agitation of the bath and coupling the two methods to compare the results. For each dyeing, the exhaustion curves of the dye bath were determined and the better results of dyeing kinetics were obtained with ultrasound coupled with mechanical stirring. Hence the corresponding half dyeing times, absorption rate constants according to Cegarra-Puente modified equation and ultrasonic efficiency were calculated in comparison with mechanical stirring alone. In the presence of ultrasound the absorption rate constants increased by at least 50%, at each temperature, confirming the synergic effect of sonication on the dyeing kinetics. Moreover the apparent activation energies were also evaluated and the positive effect of ultrasound was ascribed to the pre-exponential factor of the Arrhenius equation. It was also shown that the effect of ultrasound at 60 °C was just on the dye bath, practically unaffecting the wool fiber surface, as confirmed by the results of SEM analysis. Finally, fastness tests to rubbing and domestic laundering yielded good values for samples dyed in ultrasound assisted process even at the lower temperature. These results suggest the possibility, thanks to the use of ultrasound, to obtain a well equalized dyeing on wool working yet at 60°C, a temperature process strongly lower than 98°C, currently used in industry, which damages the mechanical properties of the fibers. PMID:22055328

Ferrero, F; Periolatto, M

2012-05-01

387

Powder Dyeing Method for Cosmetics.  

National Technical Information Service (NTIS)

A powder dyeing method for cosmetics is described that is characterized in that dyes or pigments are dispersed in water or alcohol, the solution or dispersion is mixed with porous adsorbant such as silicon dioxide or alumina powder and dried, and the drie...

S. Iwao

1974-01-01

388

Dendrimers and dyes — a review  

Microsoft Academic Search

Dendrimers are a class of macromolecules characterized by a highly branched structure of great regularity, a compact shape, a large number of (reactive) end groups, and room between the branches for taking up guest molecules. Dyes have been used to probe the structure of dendrimers; special combinations of dyes and dendrimers can be used to capture and transfer photon energy.

Peter E Froehling

2001-01-01

389

Decolorization Of Textile Dye Solutions  

Microsoft Academic Search

Results are presented on the use of ozone to decolorize textile dye solutions. The results describe the rates of reaction and the stoichiometry for the use of ozone to decolorize a simulated wastewater containing a bisazo acid dye (Acid Red 158). These rates of reaction are not sensitive to pH and are only mildly affected by temperature. The effects of

Julie Carrière; J. Peter Jones; Arthur D. Broadbent

1993-01-01

390

Optofluidic Distributed Feedback Dye Lasers  

Microsoft Academic Search

We review our recent work on poly(dimethylsiloxane) (PDMS)-based optofluidic dye lasers using a guided wave distributed feedback (DFB) cavity. We show experimental results of single-mode operation, an integrated laser array, multiple color dye lasing, mechanical and fluidic tuning, and monolithic integration with microfluidic circuits. Potential applications and future directions are discussed

Zhenyu Li; Demetri Psaltis

2007-01-01

391

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The outstanding characteristics of dye tracing are: (1) the low detection and measurement limits, and (2) the simplicity and accuracy of measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a general guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section is included on aerial photography because of its possible use to supplement ground-level fluorometry. (USGS)

Wilson, James E., Jr.; Cobb, E. D.; Kilpatrick, F. A.

1984-01-01

392

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section on aerial photography is included because of its possible use to supplement ground-level fluorometry.

Wilson, James F.

1968-01-01

393

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section on aerial photography is included because of its possible use to supplement ground-level fluorometry.

Wilson, James F.; Cobb, Ernest D.; Kilpatrick, F. A.

1986-01-01

394

Effects of pH of Dyes on Characteristics of Dye-Sensitized Solar Cells  

Microsoft Academic Search

Dye-sensitized solar cells were fabricated using natural dyes and synthesized dyes in which rear metal was not contained. Effects of pH of dyes on the characteristics of the dye-sensitized solar cells were also examined. As a result, it was found that the conversion efficiency of the dye-sensitized solar cell fabricated using red-cabbage dye with a pH of 2.5 was 0.10

Shoji Furukawa; Hiroshi Iino; Koudai Kukita; Kaoru Kaminosono

2010-01-01

395

Recent Advances in Heterogeneous Photocatalytic Decolorization of Synthetic Dyes  

PubMed Central

During the process and operation of the dyes, the wastes produced were commonly found to contain organic and inorganic impurities leading to risks in the ecosystem and biodiversity with the resultant impact on the environment. Improper effluent disposal in aqueous ecosystems leads to reduction of sunlight penetration which in turn diminishes photosynthetic activity, resulting in acute toxic effects on the aquatic flora/fauna and dissolved oxygen concentration. Recently, photodegradation of various synthetic dyes has been studied in terms of their absorbance and the reduction of oxygen content by changes in the concentration of the dye. The advantages that make photocatalytic techniques superior to traditional methods are the ability to remove contaminates in the range of ppb, no generation of polycyclic compounds, higher speed, and lower cost. Semiconductor metal oxides, typically TiO2, ZnO, SnO, NiO, Cu2O, Fe3O4, and also CdS have been utilized as photocatalyst for their nontoxic nature, high photosensitivity, wide band gap and high stability. Various process parameters like photocatalyst dose, pH and initial dye concentrations have been varied and highlighted. Research focused on surface modification of semiconductors and mixed oxide semiconductors by doping them with noble metals (Pt, Pd, Au, and Ag) and organic matter (C, N, Cl, and F) showed enhanced dye degradation compared to corresponding native semiconductors. This paper reviews recent advances in heterogeneous photocatalytic decolorization for the removal of synthetic dyes from water and wastewater. Thus, the main core highlighted in this paper is the critical selection of semiconductors for photocatalysis based on the chemical, physical, and selective nature of the poisoning dyes.

Muhd Julkapli, Nurhidayatullaili; Bagheri, Samira; Bee Abd Hamid, Sharifah

2014-01-01

396

Effect of a sulfonated azo dye and sulfanilic acid on nitrogen transformation processes in soil.  

PubMed

Introduction of organic dyes into soil via wastewater and sludge applications has been of increasing concern especially in developing or under-developed countries where appropriate management strategies are scarce. Assessing the response of terrestrial ecosystems to organic dyes and estimating the inhibition concentrations will probably contribute to soil remediation studies in regions affected by the same problem. Hence, an incubation study was conducted in order to investigate the impact of a sulfonated azo dye, Reactive Black 5 (RB5) and sulfanilic acid (SA), a typical representative of aromatic sulfonated amines, on soil nitrogen transformation processes. The results apparently showed that nitrogen related processes in soil can be used as bioindicators of anthropogenic stress caused by organic dyes. It was found that urease activity, arginine ammonification rate, nitrification potential and ammonium oxidising bacteria numbers decreased by 10-20% and 7-28% in the presence of RB5 (> 20 mg/kg dry soil) and SA (> 8 mg/kg dry soil), respectively. Accordingly, it was concluded that organic dye pollution may restrict the nitrogen-use-efficiency of plants, thus further reducing the productivity of terrestrial ecosystems. Furthermore, the response of soil microbiota to SA suggested that inhibition effects of the organic dye may continue after the possible reduction of the parent dye to associated aromatic amines. PMID:19524359

Topaç, F Olcay; Dindar, Efsun; Uçaro?lu, Selnur; Ba?kaya, Hüseyin S

2009-10-30

397

Eco-friendly dyeing of wool using natural dye from weld as copartner with synthetic dye  

Microsoft Academic Search

Since the last decade, the application of natural dyes on textile materials is gaining popularity all over the world, possibly because of increasing awareness of environment, ecology, and pollution control. In this research, extraction of dyes from weld using soxhlet apparatus has been studied. The color components extracted and isolated from weld plant were characterized by Column Chromatography, Thin Layer

Mohammad Mirjalili; Khosro Nazarpoor; Loghman Karimi

2011-01-01

398

Analysis of Insecticide Resistance-Related Genes of the Carmine Spider Mite Tetranychus cinnabarinus Based on a De Novo Assembled Transcriptome  

PubMed Central

The carmine spider mite (CSM), Tetranychus cinnabarinus, is an important pest mite in agriculture, because it can develop insecticide resistance easily. To gain valuable gene information and molecular basis for the future insecticide resistance study of CSM, the first transcriptome analysis of CSM was conducted. A total of 45,016 contigs and 25,519 unigenes were generated from the de novo transcriptome assembly, and 15,167 unigenes were annotated via BLAST querying against current databases, including nr, SwissProt, the Clusters of Orthologous Groups (COGs), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). Aligning the transcript to Tetranychus urticae genome, the 19255 (75.45%) of the transcripts had significant (e-value <10?5) matches to T. urticae DNA genome, 19111 sequences matched to T. urticae proteome with an average protein length coverage of 42.55%. Core Eukaryotic Genes Mapping Approach (CEGMA) analysis identified 435 core eukaryotic genes (CEGs) in the CSM dataset corresponding to 95% coverage. Ten gene categories that relate to insecticide resistance in arthropod were generated from CSM transcriptome, including 53 P450-, 22 GSTs-, 23 CarEs-, 1 AChE-, 7 GluCls-, 9 nAChRs-, 8 GABA receptor-, 1 sodium channel-, 6 ATPase- and 12 Cyt b genes. We developed significant molecular resources for T. cinnabarinus putatively involved in insecticide resistance. The transcriptome assembly analysis will significantly facilitate our study on the mechanism of adapting environmental stress (including insecticide) in CSM at the molecular level, and will be very important for developing new control strategies against this pest mite.

Liu, Yanchao; Liu, Xing; Chen, Qiushuang; Peng, Miao; Wang, Xiangzun; Shen, Guangmao; He, Lin

2014-01-01

399

Toxicity assessment and microbial degradation of azo dyes.  

PubMed

Toxic effluents containing azo dyes are discharged from various industries and they adversely affect water resources, soil fertility, aquatic organisms and ecosystem integrity. They pose toxicity (lethal effect, genotoxicity, mutagenicity and carcinogenicity) to aquatic organisms (fish, algae, bacteria, etc.) as well as animals. They are not readily degradable under natural conditions and are typically not removed from waste water by conventional waste water treatment systems. Benzidine based dyes have long been recognized as a human urinary bladder carcinogen and tumorigenic in a variety of laboratory animals. Several microorganisms have been found to decolourize, transform and even to completely mineralize azo dyes. A mixed culture of two Pseudomonas strains efficiently degraded mixture of 3-chlorobenzoate (3-CBA) and phenol/cresols. Azoreductases of different microorganisms are useful for the development of biodegradation systems as they catalyze reductive cleavage of azo groups (-N=N-) under mild conditions. In this review, toxic impacts of dyeing factory effluents on plants, fishes, and environment, and plausible bioremediation strategies for removal of azo dyes have been discussed. PMID:16924831

Puvaneswari, N; Muthukrishnan, J; Gunasekaran, P

2006-08-01

400

Natural dyes as photosensitizers for dye-sensitized solar cell  

Microsoft Academic Search

The dye-sensitized solar cells (DSC) were assembled by using natural dyes extracted from black rice, capsicum, erythrina variegata flower, rosa xanthina, and kelp as sensitizers. The ISC from 1.142mA to 0.225mA, the VOC from 0.551V to 0.412V, the fill factor from 0.52 to 0.63, and Pmax from 58?W to 327?W were obtained from the DSC sensitized with natural dye extracts.

Sancun Hao; Jihuai Wu; Yunfang Huang; Jianming Lin

2006-01-01

401

Hybridization of layered niobates with cationic dyes  

Microsoft Academic Search

The hybridization of two different types of organic polycations, 1,1’-dimethyl-4,4’-bipyridinium dications (methyl viologen,\\u000a MV2+) and 5,10,15,20-tetrakis(N-methyl-pyridinium-4-yl)-21H,23H-porphine tetracations (TMPyP4+), into layered niobates was investigated to construct an efficient dye-modified semiconductor for solar conversion and storage.\\u000a Two different methods were employed for the direct intercalation of the cationic species, i.e., conventional ion-exchange\\u000a with K4Nb6O17 3H2O as the starting host and a novel

Takeshi Hattori; Zhiwei Tong; Yoshiyuki Kasuga; Yoshikazu Sugito; Tatsuto Yui; Katsuhiko Takagi

2006-01-01

402

Flexible solid-state dye solar cells  

NASA Astrophysics Data System (ADS)

The cell structure concepts and materials to build solid-state dye solar cells based on nanocristalline titanium oxide and an organic hole conductor were investigated. The substrate cell is based on a metal foil and a semi-transparent gold window on top of the cell structure and the superstrate cell is deposited on ITO coated polymer foil replacing the traditional conductive glass as transparent substrate. Steel, titanium and polymer foil based cell were assembled. The polymer/ITO cell gave only small currents as the materials are far from optimal in that configuration, but an efficiency of 0.8 % was obtained on a Ti-foil based cell.

Meyer, Toby B.; Meyer, Andreas F.; Ginestoux, Daniel

2002-02-01

403

High-performance dye-sensitized solar cell with a multiple dye system  

NASA Astrophysics Data System (ADS)

A dye-sensitized solar cell (DSC) using two dyes achieved high external quantum efficiency as sensitizers. We confirmed that terpyridine complex (black dye, Solaronix) and an indoline dye (D131, Mitsubishi Paper Mill) were adsorbed by the TiO2 electrode without either dye interfering with the electron transfer of the other dye to the electrode. The high performance of the new arrangement is made possible by the dissociation function of these two particular dyes. The multiple dye system achieved a power conversion efficiency of 11.0%. Moreover, the fabrication of the multiple dye system only mixed the two reagents in one pot.

Ogura, Reiko Yoneya; Nakane, Shigeru; Morooka, Masahiro; Orihashi, Masaki; Suzuki, Yusuke; Noda, Kazuhiro

2009-02-01

404

Methylene blue dye as an alternative to isosulfan blue dye for sentinel lymph node localization.  

PubMed

Isosulfan blue dye has been used with increasing frequency in localizing sentinel lymph nodes in breast cancer patients. Few alternative types of dye have been investigated. In a prospective study of 30 patients, methylene blue dye was used instead of isosulfan blue dye to localize the sentinel lymph node. The methylene blue dye localization technique was successful in 90% of patients. These results are similar to those for isosulfan blue dye. This study describes methylene blue dye localization as a successful alternative to isosulfan dye in identifying the sentinel node in breast cancer patients. The methylene blue dye technique offers a substantial cost reduction. PMID:11469932

Simmons, R M; Smith, S M; Osborne, M P

2001-01-01

405

Dye-sensitized anodic TiO2 nanotubes  

Microsoft Academic Search

In this work, we report on dye-sensitization of self-organized TiO 2 nanotubes and the photoelectrochemical response of this system. The tubes were grown by Ti anodization in fluoride containing electrolytes in two different forms as \\

Jan M. Macák; Hiroaki Tsuchiya; Andrej Ghicov; Patrik Schmuki

2005-01-01

406

“Critical” effect of hydrogen peroxide in photochemical dye degradation  

Microsoft Academic Search

Tertiary or pretreatment of dyeing effluents by advanced oxidation processes (AOP) catalyzed by a source of UV light and a powerful oxidant is a promising alternative for the effective removal of color and refractory organics from the effluent. A crucial feature in designing such systems is the optimization of operating conditions (such as UV and oxidant dosages), which yield maximum

Nilsun H. Ince

1999-01-01

407

Convenient Microscale Synthesis of a Coumarin Laser Dye Analog  

ERIC Educational Resources Information Center

Coumarin (2H-1-benzopyran-2-one) and its derivatives constitute a fascinating class of organic substances that are utilized industrially in areas such as cosmetics, food preservatives, insecticides and fluorescent laser dyes. The product can be synthesized, purified, and characterized within two hours with benefits of microscale reactivity being…

Aktoudianakis, Evangelos; Dicks, Andrew P.

2006-01-01

408

Dye-sensitized solar cells  

DOEpatents

A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

Skotheim, Terje A. (Berkeley, CA)

1980-01-01

409

Dye-sensitized solar cells  

DOEpatents

A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

Skotheim, T.A.

1980-03-04

410

Interfacial Properties of a Hydrophobic Dye in the Tetrachalorethylene- Water-Glass Systems.  

National Technical Information Service (NTIS)

Interfacial effects play an important role in governing multiphase fluid behavior in porous media. Strongly hydrophobic organic dyes, used in many experimental studies to facilitate visual observation of the phase distributions, have generally been implic...

D. M. Tuck

1999-01-01

411

NaNO 2\\/FeCl 3 dioxygen recyclable activator: An efficient approach to active oxygen species for degradation of a broad range of organic dye pollutants in water  

Microsoft Academic Search

A combination of ferric chloride and sodium nitrite is a competent catalyst for catalytic bleaching of a broad range of dye pollutants under moderate condition (T=150°C; oxygen pressure=0.5MPa; pH 2.5). To evaluate the catalytic degradation system, we implemented wet oxidation of Acid Blue 129 (AB129) at the temperatures between 110 and 150°C using FeCl3\\/NaNO2 as the catalyst. The degradation process

Yanrong Peng; Dongmei Fu; Renhua Liu; Feifang Zhang; Xingya Xue; Qing Xu; Xinmiao Liang

2008-01-01

412

Never say dye  

PubMed Central

Recent years have seen a remarkable increase in the number of publications dealing with the application of epifluorescence microscopy in cell biology. This can be widely attributed to the development of state-of-the-art image processing programs, as well as the development of new reagents/probes, which allow the labeling of most cell structures, organelles and metabolites with high specificity. However, the use of a specific fluorescent dye, 3,3?-dihexyloxacarbocyanine iodide (DiOC6), has been recently revisited and several new application potentials have emerged. The goal of this mini-review is to provide an up-to-date overview of the multiple roles of this multifaceted probe.

2012-01-01

413

Multiwavelength dye laser  

SciTech Connect

The problems of collimating, synchronizing and combining a plurality of laser beams to generate a composite beam are substantially reduced by the use of one or more lasers especially adapted to lase in two or more separate wavelengths. Specifically , a composite beam generating system comprises at least one multiwavelength laser for emitting a multiwavelength beam having at least two separated wavelength components, one or more additional lasers for generating respective additional beams, and means for combining the multiwavelength beam with one or more additional beams. In a preferred embodiment, a four-component multiwavelength composite beam is generated by polarization combination of the outputs of a pair of orthogonally polarized two-component multiwavelength lasers. The preferred embodiment of a multiwavelength laser is a liquid dye laser having, as one of the reflecting means defining the resonant cavity, an optical reflector having a reflectivity versus wavelength characteristic with a local minimum of reflectivity between two regions of substantially greater reflectivity.

Draggoo, V.; Mcallister, G.L.

1981-10-06

414

Dyeing Properties of Natural Dye Syzygium cuminii on Silk  

NASA Astrophysics Data System (ADS)

Dyeing behavior of natural dye extracted from the bark of Syzygium cuminii L has been studied on silk fabric. Colour values and colour co-ordinates were examined in terms of K/S and L* a* b* C and h. A range of shades were obtained by using various mordants and mordanting techniques. Dye was tested for some of the eco-parameters using atomic absorption spectrophotometry and GC/MS. The test results were compared with the set standards to determine the eco-friendliness of natural dye. Their concentrations were much below the stipulated limits. Dyed samples were tested for antimicrobial activity against Gram-positive and Gram-negative bacteria and were found to possess antibacterial activity.

Narayana Swamy, V.; Ninge Gowda, K. N.; Sudhakar, R.

2014-06-01

415

Decolorization and Detoxification of Textile Dyes with a Laccase from Trametes hirsuta  

PubMed Central

Trametes hirsuta and a purified laccase from this organism were able to degrade triarylmethane, indigoid, azo, and anthraquinonic dyes. Initial decolorization velocities depended on the substituents on the phenolic rings of the dyes. Immobilization of the T. hirsuta laccase on alumina enhanced the thermal stabilities of the enzyme and its tolerance against some enzyme inhibitors, such as halides, copper chelators, and dyeing additives. The laccase lost 50% of its activity at 50 mM NaCl while the 50% inhibitory concentration (IC50) of the immobilized enzyme was 85 mM. Treatment of dyes with the immobilized laccase reduced their toxicities (based on the oxygen consumption rate of Pseudomonas putida) by up to 80% (anthraquinonic dyes). Textile effluents decolorized with T. hirsuta or the laccase were used for dyeing. Metabolites and/or enzyme protein strongly interacted with the dyeing process indicated by lower staining levels (K/S) values than obtained with a blank using water. However, when the effluents were decolorized with immobilized laccase, they could be used for dyeing and acceptable color differences (?E*) below 1.1 were measured for most dyes.

Abadulla, Elias; Tzanov, Tzanko; Costa, Silgia; Robra, Karl-Heinz; Cavaco-Paulo, Artur; Gubitz, Georg M.

2000-01-01

416

Design and synthesis of polymer-functionalized NIR fluorescent dyes--magnetic nanoparticles for bioimaging.  

PubMed

The fluorescent probes having complete spectral separation between absorption and emission spectra (large Stokes shift) are highly useful for solar concentrators and bioimaging. In bioimaging application, NIR fluorescent dyes have a greater advantage in tissue penetration depth compared to visible-emitting organic dyes or inorganic quantum dots. Here we report the design, synthesis, and characterization of an amphiphilic polymer, poly(isobutylene-alt-maleic anhyride)-functionalized near-infrared (NIR) IR-820 dye and its conjugates with iron oxide (Fe3O4) magnetic nanoparticles (MNPs) for optical and magnetic resonance (MR) imaging. Our results demonstrate that the Stokes shift of unmodified dye can be tuned (from ~106 to 208 nm) by the functionalization of the dye with polymer and MNPs. The fabrication of bimodal probes involves (i) the synthesis of NIR fluorescent dye (IR-820 cyanine) functionalized with ethylenediamine linker in high yield, >90%, (ii) polymer conjugation to the functionalized NIR fluorescent dye, and (iii) grafting the polymer-conjugated dyes on iron oxide MNPs. The resulting uniform, small-sized (ca. 6 nm) NIR fluorescent dye-magnetic hybrid nanoparticles (NPs) exhibit a wider emissive range (800-1000 nm) and minimal cytotoxicity. Our preliminary studies demonstrate the potential utility of these NPs in bioimaging by means of direct labeling of cancerous HeLa cells via NIR fluorescence microscopy and good negative contrast enhancement in T2-weighted MR imaging of a murine model. PMID:23869722

Yen, Swee Kuan; Ja?czewski, Dominik; Lakshmi, Jeeva Lavanya; Dolmanan, Surani Bin; Tripathy, Sudhiranjan; Ho, Vincent H B; Vijayaragavan, Vimalan; Hariharan, Anushya; Padmanabhan, Parasuraman; Bhakoo, Kishore K; Sudhaharan, Thankiah; Ahmed, Sohail; Zhang, Yong; Tamil Selvan, Subramanian

2013-08-27

417

Degradation of Acid Blue 40 dye solution and dye house wastewater from textile industry by photo-assisted electrochemical process  

Microsoft Academic Search

In this paper, electrochemical and photo-assisted electrochemical processes are used for color, total organic carbon (TOC) and chemical oxygen demand (COD) degradation of one of the most abundant and strongly colored industrial wastewaters, which results from the dyeing of fibers and fabrics in the textile industry. The experiments were carried out in an 18 L pilot-scale tubular flow reactor with

Peterson B. Moraes; Rosangela R. L. Pelegrino; Rodnei Bertazzoli

2007-01-01

418

Efficiency and photostability of dye-doped solid-state lasers in different hosts  

NASA Astrophysics Data System (ADS)

We survey the preparation procedures of pyrromethene (PM) and rhodamine dyes in silica, silica-zirconia, organically modified silicate (ormosil) and organic polymer matrices. Absorption and luminescence spectra, as well as decay time fluorescence of pyrromethene dyes are given. The solid-state laser samples were tested and their efficiencies and photostabilities at transversal pumping configuration, are given. Pyrromethene 597 had the best laser dye performance with slope efficiency of 43.3% when doped in ormosil glass and high photostability when doped in poly(methyl methacrylate) (PMMA) . Analysis and explanations for the results are given.

Yariv, Eli; Schultheiss, Silke; Saraidarov, Tsiala; Reisfeld, Renata

2001-02-01

419

Design and synthesis of a noncentrosymmetric Dipyrromethene Dye  

SciTech Connect

Semiempirical methods were applied to the design of a new second order nonlinear optical (NLO) dye through noncentrosymmetric modifications to the symmetric dipyrromethene boron difluoride chromophore. Computational evaluations of candidate structures suggested that a synthetically accessible methoxyindole modification would have second order NLO properties. This new dye consists of 4 fused rings, is soluble in polar organic solvents and has a large molar extinction coefficient (86 {times} 103). Its measured hyperpolarizability, {beta}, is -44 {times} 10{sup {minus}30} esu at 1367 nm. The methoxyindole therefore induces moderate asymmetry to the chromophore.

Meinhardt, M.B.; Cahill, P.A. [Sandia National Labs., Albuquerque, NM (United States); Kowalczyk, T.C.; Singer, K.D. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Physics

1994-12-31

420

Picosecond distributed feedback dye lasers  

SciTech Connect

The distributed feedback dye laser is a source of single picosecond pulses tunable in a very wide wavelength range. Operational principles, experimental arrangements, and recent applications are reviewed in this paper.

Bor, Z.; Muller, A.

1986-08-01

421

Whole-cell fungal transformation of precursors into dyes  

PubMed Central

Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25). Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid) into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other commercially important products. The use of immobilized fungal biomass limits free migration of cells and facilitates their reuse in a continuous system for precursor transformation.

2010-01-01

422

Determination of Degraded Dyes and Auxiliary Chemicals in Effluents from Textile Dyeing Processes.  

National Technical Information Service (NTIS)

Selected dyes and auxiliary chemicals used in dyeing processes were tested in a laboratory environment simulating that to which dyehouse effluents would be subjected in a conventional activated sludge waste treatment process. Dyes and auxiliary chemicals ...

R. K. Flege

1970-01-01

423

Dye molecules in electrolytes: new approach for suppression of dye-desorption in dye-sensitized solar cells  

PubMed Central

The widespread commercialization of dye-sensitized solar cells remains limited because of the poor long-term stability. We report on the influence of dye-molecules added in liquid electrolyte on long-term stability of dye-sensitized solar cells. Dye-desorption from the TiO2 surface during long-term cycling is one of the decisive factors that degrade photocurrent densities of devices which in turn determine the efficiencies of the devices. For the first time, desorption of dye from the TiO2 surface could be suppressed by controlling thermodynamic equilibrium; by addition of dye molecules in the electrolyte. The dye molecules in the electrolyte can suppress the driving forces for the adsorbed dye molecules to be desorbed from TiO2 nanoparticles. As a result, highly enhanced device stabilities were achieved due to the reduction of dye-desorption although there was a little decrease in the initial efficiencies.

Heo, Nansra; Jun, Yongseok; Park, Jong Hyeok

2013-01-01

424

Photoelectrochemical properties of the CT1 dye: A DFT study  

NASA Astrophysics Data System (ADS)

We report a comprehensive computational study on the electronic and optical properties of a hemi-squaraine organic dye recently proposed for Dye Sensitized Solar Cells (DSSCs) applications. Ground and excited state properties have been computed within DFT and TD-DFT approaches, respectively. Results from 10 different functionals ranging from pure GGA (mPW91 and PBE), to global hybrids (B3LYP, PBE0, mPW1K and M05-2X) and range separated hybrids (?-B97X, LC-?PBE, CAM-B3LYP and HSE06) have been analyzed and compared to available experimental data. Aggregation effects on the electrochemical and optical properties of the dye have been also analyzed.

Camino, Bruno; De La Pierre, Marco; Ferrari, Anna Maria

2013-08-01

425

Dye removal by immobilised fungi.  

PubMed

Dyes are widely used within the food, pharmaceutical, cosmetic, printing, textile and leather industries. This has resulted in the discharge of highly coloured effluents that affect water transparency and gas solubility in water bodies. Furthermore, they pose a problem because of their carcinogenicity and toxicity. Therefore, removal of such dyes before discharging them into natural water streams is essential. For this, appropriate treatment technologies are required. The treatment of recalcitrant and toxic dyes with traditional technologies is not always effective or may not be environmentally friendly. This has impelled the search for alternative technologies such as biodegradation with fungi. In particular, ligninolytic fungi and their non-specific oxidative enzymes have been reported to be responsible for the decolouration of different synthetic dyes. Thus, the use of such fungi is becoming a promising alternative to replace or complement the current technologies for dye removal. Processes using immobilised growing cells seem to be more promising than those with free cells, since the immobilisation allows using the microbial cells repeatedly and continuously. This paper reviews the application of fungal immobilisation to dye removal. PMID:19211032

Rodríguez Couto, Susana

2009-01-01

426

New active media based on bifluorophormic compounds for dye lasers  

NASA Astrophysics Data System (ADS)

The photophysical properties (photostability, spectral-luminescent and generation properties) of eight new organic compounds have been studied, in which the molecular composition of two flurophores -- 1,3,5-triphenylpyrazoline and 2,5-diphenylzoxazole-1,3 (or 2,5- diphenyloxazole-1,3,4) -- were included. The effect of the structure of the investigated molecules and the polar properties of solvents on the spectral position of absorption and fluorescence bands was analyzed. The dyes have been found to have a fluorescence quantum efficiency (gamma) between 0.40 and 0.82 in these solvents. The dye laser performance using these dyes has also been investigated using the same solvents under nitrogen-laser pumping to compare them with the commercially available standard dye POPOP, which generates radiation in the violet spectrum region and allows the extension of the range of the active media used in liquid lasers in this spectrum region. A tuning range of nearly 60 nm was obtained in the blue region with efficiency up to 85% in comparison to the standard dye POPOP.

Neyra Bueno, O. L.; Gruzinskiy, V. V.; Seniuk, M. A.; Afanasiady, L. S.

1996-02-01

427

Dye laser amplifier including a dye cell contained within a support vessel  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of greater than 30 gallons/minute at a static pressure greater than 150 pounds/square inch and a specifically designed support vessel for containing the dye cell. 6 figs.

Davin, J.

1992-12-01

428

Dye laser amplifier including a dye cell contained within a support vessel  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of greater than 30 gallons/minute at a static pressure greater than 150 pounds/square inch and a specifically designed support vessel for containing the dye cell.

Davin, James (Gilroy, CA)

1992-01-01

429

Fluorescein dye intercalated layered double hydroxides for chemically stabilized photoluminescent indicators on inorganic surfaces.  

PubMed

A new photoactive thin film of layered double hydroxide (LDH) nanocrystals containing fluorescein dyes (LDH-F) has been developed by self-assembly of the LDH nanocrystals and well-controlled intercalation of the dyes in organic media. XRD results and absorption spectra confirmed the highly oriented interlayer arrangement of the dianionic form of the fluorescein dyes in the LDH interlayers, in which the dye molecules were electrostatically immobilized between the positively charged LDH layers with a monolayer packing structure. An intensity weighted average PL lifetime was estimated to be 1.45 ns and fluorescence lifetime imaging microscopy revealed that the individual LDH nanocrystals on the LDH-F film had largely similar lifetimes, which were ascribed to the uniform loading of fluorescein dyes onto the LDH matrix without photoluminescence quenching. PMID:24759944

Lee, Jong Hyeon; Jung, Duk-Young; Kim, Eunchul; Ahn, Tae Kyu

2014-06-14

430

A vibrational spectroscopic and principal component analysis of triarylmethane dyes by comparative laboratory and portable instrumentation.  

PubMed

This contribution examines the utility of vibrational spectroscopy by bench and portable Raman/surface enhanced Raman and infrared methods for the investigation of ten early triarlymethane dye powder references and dye solutions applied on paper. The complementary information afforded by the techniques is shown to play a key role in the identification of specific spectral marker ranges to distiguish early synthetic dyes of art-historical interest through the elaboration of an in-house database of modern organic dyes. Chemometric analysis has permitted a separation of data by the discrimination of di-phenyl-naphthalenes and triphenylmethanes (di-amino and tri-amino derivatives). This work serves as a prelude to the validation of a non-invasive working method for in situ characterization of these synthetic dyes through a careful comparison of respective strengths and limitations of each portable technique. PMID:24252295

Doherty, B; Vagnini, M; Dufourmantelle, K; Sgamellotti, A; Brunetti, B; Miliani, C

2014-03-01

431

Cobalt electrolyte/dye interactions in dye-sensitized solar cells: a combined computational and experimental study.  

PubMed

We report a combined experimental and computational investigation to understand the nature of the interactions between cobalt redox mediators and TiO(2) surfaces sensitized by ruthenium and organic dyes, and their impact on the performance of the corresponding dye-sensitized solar cells (DSSCs). We focus on different ruthenium dyes and fully organic dyes, to understand the dramatic loss of efficiency observed for the prototype Ru(II) N719 dye in conjunction with cobalt electrolytes. Both N719- and Z907-based DSSCs showed an increased lifetime in iodine-based electrolyte compared to the cobalt-based redox shuttle, while the organic D21L6 and D25L6 dyes, endowed with long alkoxy chains, show no significant change in the electron lifetime regardless of employed electrolyte and deliver a high photovoltaic efficiency of 6.5% with a cobalt electrolyte. Ab initio molecular dynamics simulations show the formation of a complex between the cobalt electrolyte and the surface-adsorbed ruthenium dye, which brings the [Co(bpy)(3)](3+) species into contact with the TiO(2) surface. This translates into a high probability of intercepting TiO(2)-injected electrons by the oxidized [Co(bpy)(3)](3+) species, lying close to the N719-sensitized TiO(2) surface. Investigation of the dye regeneration mechanism by the cobalt electrolyte in the Marcus theory framework led to substantially different reorganization energies for the high-spin (HS) and low-spin (LS) reaction pathways. Our calculated reorganization energies for the LS pathways are in excellent agreement with recent data for a series of cobalt complexes, lending support to the proposed regeneration pathway. Finally, we systematically investigate a series of Co(II)/Co(III) complexes to gauge the impact of ligand substitution and of metal coordination (tris-bidentate vs bis-tridentate) on the HS/LS energy difference and reorganization energies. Our results allow us to trace structure/property relations required for further development of cobalt electrolytes for DSSCs. PMID:23113640

Mosconi, Edoardo; Yum, Jun-Ho; Kessler, Florian; Gómez García, Carlos J; Zuccaccia, Cristiano; Cinti, Antonio; Nazeeruddin, Mohammad K; Grätzel, Michael; De Angelis, Filippo

2012-11-28

432

Vital dyes in ophthalmology: a chemical perspective.  

PubMed

Abstract Vital dyes have advanced diagnosis and surgical technique in various specialties, including oncology, gastroenterology and ophthalmology. Intra-operative and diagnostic dyes are finding uses in all areas of ophthalmology, including cornea, cataract, retina, glaucoma, orbit and conjunctiva. We provide a summary of current knowledge of the chemical concepts of vital dyes in ophthalmology. We review the properties of dyes, techniques of application, indications and complications in ocular surgery. Vital dyes represent an expanding area of research, and novel dyes deserve further investigation. PMID:24400745

Badaro, Emmerson; Novais, Eduardo Amorim; Penha, Fernando Marcondes; Maia, Mauricio; Farah, Michel Eid; Rodrigues, Eduardo Buchele

2014-07-01

433

Sea dye marker provides visibility for 20 hours  

NASA Technical Reports Server (NTRS)

Sea dye marker block releases a visible slick which lasts at least twelve hours. The dye marker uses a fluorescent dye in a heat cured binder which, when immersed in seawater, releases the dye at a controlled rate.

De Laat, F.

1966-01-01

434

LASERS: A microporous glass-polymer composite as a new material for solid-state dye lasers: II. Lasing properties  

Microsoft Academic Search

The conversion efficiency and service life of the laser elements based on a polymer-filled microporous glass (PFMPG) composite doped with organic dyes are studied. It is shown that both the conversion efficiency and the service life of the laser elements achieve the values obtained for the same dyes in bulk polymer elements. Good lasing characteristics of the elements studied are

H. R. Aldag; S. M. Dolotov; M. F. Koldunov; Ya V. Kravchenko; Aleksandr A. Manenkov; D. P. Pacheco; E. P. Ponomarenko; A. V. Reznichenko; G. P. Roskova; T. S. Tsekhomskaya

2000-01-01

435

Study of the white-rot fungal degradation of selected phthalocyanine dyes by capillary electrophoresis and liquid chromatography  

Microsoft Academic Search

The phthalocyanine dyes, Remazol Turquoise Blue G133, Everzol Turquoise Blue and Heligon Blue S4 are found to be biosorbed by Phanerochaete chrysosporium (white-rot fungi) and also metabolised by its ligninolytic extracellular enzymes resulting in dye decolourisation, formation of free copper ions and organic metabolites with ultimate extensive phthalocyanine ring breakdown. It is believed that the ligninolytic extracellular enzyme laccase is

A. Conneely; W. F. Smyth; G. McMullan

2002-01-01

436

Standardization of reagents and methods used in cytological and histological practice with emphasis on dyes, stains and chromogenic reagents  

Microsoft Academic Search

Summary  The need for the standardization of reagents and methods used in the histology laboratory is demonstrated. After definitions of dyes, stains, and chromogenic reagents, existing standards and standards organizations are discussed. This is followed by practical instructions on how to standardize dyes and stains through the preparation of reference materials and the development of chromatographic methods. An overview is presented

H. O. Lyon; A. P. De Leenheer; R. W. Horobin; W. E. Lambert; E. K. W. Schulte; B. Van Liedekerke; D. H. Wittekind

1994-01-01

437

Anaerobic decolorization bacteria for the treatment of azo dye in a sequential anaerobic and aerobic membrane bioreactor  

Microsoft Academic Search

Textile dyeing wastewater is harmful to both marine organisms and human beings. This study focused on the treatment of wastewater containing an azo dye, Reactive Black 5 (RB5), using an anaerobic sequencing batch reactor (SBR) combined with an aerobic membrane bioreactor (aerobic MBR). In addition the anaerobic RB5 degrading bacteria were isolated and their individual performance were tested separately. Nearly

Sheng-Jie You; Jun-Yu Teng

2009-01-01

438

Solvent effects on emission yield and lifetime for coumarin laser dyes. Requirements for a rotatory decay mechanism  

Microsoft Academic Search

Photophysical parameters have been determined for coumarin laser dyes in a variety of organic solvents, water, and mixed media. The response of fluorescence emission yield and lifetime to changes in solvent polarity was a sensitive function of coumarin substitution pattern. Most important were substituent influences which resulted in enlarged excited-state dipole moments for the fluorescent state. For dyes displaying sharp

Guilford Jones; William R. Jackson; Chol Yoo Choi; William R. Bergmark

1985-01-01

439

Soybean peroxidase-mediated degradation of an azo dye- a detailed mechanistic study  

PubMed Central

Background Peroxidases are emerging as an important class of enzymes that can be used for the efficient degradation of organic pollutants. However, detailed studies identifying the various intermediates produced and the mechanisms involved in the enzyme-mediated pollutant degradation are not widely published. Results In the present study, the enzymatic degradation of an azo dye (Crystal Ponceau 6R, CP6R) was studied using commercially available soybean peroxidase (SBP) enzyme. Several operational parameters affecting the enzymatic degradation of dye were evaluated and optimized, such as initial dye concentration, H2O2 dosage, mediator amount and pH of the solution. Under optimized conditions, 40 ppm dye solution could be completely degraded in under one minute by SBP in the presence of H2O2 and a redox mediator. Dye degradation was also confirmed using HPLC and TOC analyses, which showed that most of the dye was being mineralized to CO2 in the process. Conclusions Detailed analysis of metabolites, based on LC/MS results, showed that the enzyme-based degradation of the CP6R dye proceeded in two different reaction pathways- via symmetric azo bond cleavage as well as asymmetric azo bond breakage in the dye molecule. In addition, various critical transformative and oxidative steps such as deamination, desulfonation, keto-oxidation are explained on an electronic level. Furthermore, LC/MS/MS analyses confirmed that the end products in both pathways were small chain aliphatic carboxylic acids.

2013-01-01

440

Removal of acid and direct dye by epichlorohydrin-dimethylamine: flocculation performance and floc aggregation properties.  

PubMed

A cationic organic flocculant epichlorohydrin-dimethylamine (EPI-DMA) was employed for the treatment of acid and direct dye. The study aims at investigating the flocculation performance of EPI-DMA for the model dye, and corresponding floc aggregation properties, which were determined by jar test and photometric dispersion analysis, respectively. The interactions between cationic flocculant and anionic dye were investigated through spectra analysis. The resul