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Sample records for styryl pyridinium dyes

  1. Photophysical properties of a surfactive long-chain styryl merocyanine dye as fluorescent probe

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    Ismail, L.F.M., E-mail: Lailafmi@yahoo.com [Al-Azhar University, Faculty of Science, Chemistry Department, Nasr City, 12 Ibrahim El-Nagar, El-Hegaz Sq. Heliopolis, Cairo 11315 (Egypt)

    2012-09-15

    This work deals with detailed investigations of the photophysical properties of a styryl merocyanine dye, namely 1-cetyl-4-[4 Prime -(methoxy) styryl]-pyridinium bromide (CMSPB) of molecular rotor type. The solvatochromic analyses of the data in different solvents using the Kamlet-Taft parameters ({alpha}, {beta}, {pi}{sup Low-Asterisk }) were discussed. Optical excitation of the studied merocyanine dye populates a CT S{sub 1} state with about 22.64 folds higher dipole moment value relative to that in the S{sub 0} state. Moreover, the effect of solvent viscosity (glycerol at various temperatures (299.0-351.0 K)) on CMSPB fluorescent properties is analyzed to understand the molecular mechanisms of the characteristic increase in CMSPB fluorescence intensity. The results indicate that CMSPB exhibits fluorescent properties typical for molecular rotors. The results show that torsional relaxation dynamics of molecular rotors in high-viscosity solvents cannot be described by the simple stick boundary hydrodynamics defined by the Debye-Stokes-Einstein (DSE) equation. The fluorescence depolarization behavior in glycerol at various temperatures (299.0-351.0 K) shows that the molecular rotational diffusion is controlled by the free volume of the medium. Furthermore, excited state studies in ethanol/chloroform mixture revealed the formation of weak complex with chloroform of stoichiometry 1:1 with formation constant of 0.004l mol{sup -1}. Moreover, the increase of the quantum yield values in micellar solutions of CTAB and SDS relative to that of water indicates that the guest dye molecules are microencapsulated into the hydrophobic interior of host micelle. The obtained non-zero values of fluorescence polarization in micellar solution imply reduced rotational depolarization of dye molecules via association with the surfactant. Upon comparing the spectral data in micelles with those in homogeneous solvent systems, more can be learned of the structural details of the micellar

  2. Femtosecond dynamics of the S2 and S1 fluorescence of ionic styryl dyes in polar solvents

    NARCIS (Netherlands)

    Wang, H.; Rettig, W.; Tolmachev, A.I.; Glasbeek, M.

    2004-01-01

    Femtosecond fluorescence upconversion and picosecond time-correlated single-photon counting fluorescence experiments for bridged and unbridged ionic styryl dye compounds in polar solvents are reported. The measured fluorescence transients reveal S2 S1 internal conversion (IC) with a typical time of

  3. Voltage-sensitive styryl dyes as singlet oxygen targets on the surface of bilayer lipid membrane.

    Science.gov (United States)

    Sokolov, V S; Gavrilchik, A N; Kulagina, A O; Meshkov, I N; Pohl, P; Gorbunova, Yu G

    2016-08-01

    Photosensitizers are widely used as photodynamic therapeutic agents killing cancer cells by photooxidation of their components. Development of new effective photosensitive molecules requires profound knowledge of possible targets for reactive oxygen species, especially for its singlet form. Here we studied photooxidation of voltage-sensitive styryl dyes (di-4-ANEPPS, di-8-ANEPPS, RH-421 and RH-237) by singlet oxygen on the surface of bilayer lipid membranes commonly used as cell membrane models. Oxidation was induced by irradiation of a photosensitizer (aluminum phthalocyanine tetrasulfonate) and monitored by the change of dipole potential on the surface of the membrane. We studied the drop of the dipole potential both in the case when the dye molecules were adsorbed on the same side of the lipid bilayer as the photosensitizer (cis-configuration) and in the case when they were adsorbed on the opposite side (trans-configuration). Based on a simple model, we determined the rate of oxidation of the dyes from the kinetics of change of the potential during and after irradiation. This rate is proportional to steady-state concentration of singlet oxygen in the membrane under irradiation. Comparison of the oxidation rates of various dyes reveals that compounds of ANEPPS series are more sensitive to singlet oxygen than RH type dyes, indicating that naphthalene group is primarily responsible for their oxidation. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Synthesis, structure, and characterization of chromo(fluoro)ionophores with cation-triggered emission based on N-methylaza-crown-ether styryl dyes.

    Science.gov (United States)

    Gromov, Sergey P; Dmitrieva, Svetlana N; Vedernikov, Artem I; Kurchavov, Nikolay A; Kuz'mina, Lyudmila G; Sazonov, Sergey K; Strelenko, Yuri A; Alfimov, Michael V; Howard, Judith A K; Ushakov, Evgeny N

    2013-10-04

    Novel 2-benzothiazole-, 4-pyridine-, and 2- and 4-quinoline-based styryl dyes containing an N-methylbenzoaza-15(18)-crown-5(6)-ether moiety were synthesized. A detailed electronic spectroscopy study revealed high performance of these compounds as optical molecular sensors for alkali and alkaline-earth metal cations. They were shown to considerably surpass analogous chromoionophores based on N-phenylaza-crown ethers regarding both the ionochromism and the cation-binding ability. In addition, they act as fluorescent sensors for the metal cations by demonstrating cation-triggered emission. Upon complexation with Ba(2+), the fluorescence enhancement factor reaches 61. The structural features of dyes and their metal complexes were studied by NMR spectroscopy and X-ray diffraction. The high degree of macrocycle preorganization was found to be one of the factors determining the high cation-binding ability of the sensor molecules based on N-methylbenzoaza-crown ethers.

  5. In search of the thermo/halochromism of the ET(30) pyridinium-N-phenolate betaine dye

    Science.gov (United States)

    Rezende, Marcos Caroli; Aracena, Andrés

    2012-12-01

    The thermohalochromic behavior of Reichardt's ET(30) betaine - the temperature-dependent variation of its halochromic band in the presence of a cation - was investigated for the first time in NaI solutions of HBD- (methanol, ethanol, 1-propanol, 1-butanol) and non-HBD-solvents (acetonitrile, dimethylformamide) at 15 and 55 °C. The solvent-dependent thermohalochromism of the pyridinium-N-phenolate betaine dye was interpreted in terms of the effect of the temperature on the dye-cation association in solution.

  6. In search of the thermo/halochromism of the E(T)(30) pyridinium-N-phenolate betaine dye.

    Science.gov (United States)

    Rezende, Marcos Caroli; Aracena, Andrés

    2012-12-01

    The thermohalochromic behavior of Reichardt's E(T)(30) betaine - the temperature-dependent variation of its halochromic band in the presence of a cation - was investigated for the first time in NaI solutions of HBD- (methanol, ethanol, 1-propanol, 1-butanol) and non-HBD-solvents (acetonitrile, dimethylformamide) at 15 and 55 °C. The solvent-dependent thermohalochromism of the pyridinium-N-phenolate betaine dye was interpreted in terms of the effect of the temperature on the dye-cation association in solution. Copyright © 2012 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    2013-10-01

    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.

  8. Radioiodinated (aminostyryl)pyridinium (ASP) dyes: New cell membrane probes for labeling mixed leukocytes and lymphocytes for diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, Carol; Mease, Ronnie C.; Avren, Lee; Le, Truc; Sabet, Hassan; McAfee, John G

    1996-05-01

    We prepared [({sup 125}I({sup 131}I))]iodo-(aminostyryl)pyridinium dyes from tributylstannyl precursors. ASP 7a and 7b labeled leukocytes ex vivo (70-94%) using saline with or without washing plasma from cells. Viability of peripheral blood lymphocytes (PBLs) (dogs, rats) and splenic lymphocytes (rats) labeled with 7a and 7b (71-82%) was unchanged after labeling ({>=}88%). Canine 7b-leukocytes showed higher uptake in inflammatory lesions than did {sup 111}In-oxine leukocytes. At 3 h, aspirates contained more radioiodine than {sup 111}In (1.65:1 to 22:1) and radioiodine was cell bound. ROI measurements (3 h) gave abscess to contralateral knee ratios of 12.3 and 10.6 for {sup 131}I-7b vs. 4.8 and 2.3 for {sup 111}In-oxine.

  9. Investigation of binding properties of dicationic styrylimidazo[1,2-a]pyridinium dyes to human serum albumin by spectroscopic techniques.

    Science.gov (United States)

    Özdemir, Ayşe; Gökoğlu, Elmas; EsraYılmaz; Yalçın, Ergin; Gökoğlu, Esra; Seferoğlu, Zeynel; Tekinay, Turgay

    2017-02-01

    The binding interaction between two dicationic styrylimidazo[1,2-a]pyridinium dyes and human serum albumin (HSA) was investigated at physiological conditions using fluorescence, UV-vis absorption, and circular dichroism (CD) spectroscopies. Analysis of the fluorescence titration data at different temperatures suggested that the fluorescence quenching mechanism of HSA by these dyes was static. The calculated thermodynamic parameters (ΔG°, ΔH° and ΔS°) indicated that hydrogen bonding and van der Waals forces played a major role in the formation of the dye-HSA complex. Binding distances (r) between dyes and HSA were calculated according to Förster's non-radiative energy transfer theory. Studies of conformational changes of HSA using CD measurements indicate that the α-helical content of the protein decreased upon binding of the dyes. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  10. Thiophene-based dyes for probing membranes.

    Science.gov (United States)

    López-Duarte, Ismael; Chairatana, Phoom; Wu, Yilei; Pérez-Moreno, Javier; Bennett, Philip M; Reeve, James E; Boczarow, Igor; Kaluza, Wojciech; Hosny, Neveen A; Stranks, Samuel D; Nicholas, Robin J; Clays, Koen; Kuimova, Marina K; Anderson, Harry L

    2015-03-28

    We report the synthesis of four new cationic dipolar push–pull dyes, together with an evaluation of their photophysical and photobiological characteristics pertinent to imaging membranes by fluorescence and second harmonic generation (SHG). All four dyes consist of an N,N-diethylaniline electron-donor conjugated to a pyridinium electron-acceptor via a thiophene bridge, with either vinylene (–CH=CH–) or ethynylene (–C≡C–) linking groups, and with either singly-charged or doubly-charged pyridinium terminals. The absorption and fluorescence behavior of these dyes were compared to a commercially available fluorescent membrane stain, the styryl dye FM4-64. The hyperpolarizabilities of all dyes were compared using hyper-Rayleigh scattering at 800 nm. Cellular uptake, localization, toxicity and phototoxicity were evaluated using tissue cell cultures (HeLa, SK-OV-3 and MDA-231). Replacing the central alkene bridge of FM4-64 with a thiophene does not substantially change the absorption, fluorescence or hyperpolarizability, whereas changing the vinylene-links to ethynylenes shifts the absorption and fluorescence to shorter wavelengths, and reduces the hyperpolarizability by about a factor of two. SHG and fluorescence imaging experiments in live cells showed that the doubly-charged thiophene dyes localize in plasma membranes, and exhibit lower internalization rates compared to FM4-64, resulting in less signal from the cell cytosol. At a typical imaging concentration of 1 μM, the doubly-charged dyes showed no significant light or dark toxicity, whereas the singly-charged dyes are phototoxic even at 0.5 μM. The doubly-charged dyes showed phototoxicity at concentrations greater than 10 μM, although they do not generate singlet oxygen, indicating that the phototoxicity is type I rather than type II. The doubly-charged thiophene dyes are more effective than FM4-64 as SHG dyes for live cells.

  11. Benzocoumarin-Styryl Hybrids: Aggregation and Viscosity Induced Emission Enhancement.

    Science.gov (United States)

    Warde, Umesh; Sekar, Nagaiyan

    2017-09-01

    Two benzo[h]chromen-3-yl)ethylidene) malononitrile styryl hybrid dyes are synthesized and characterized by NMR and elemental analysis. One is based on nitrogen donor and other on oxygen (3b and 3b respectively). Dyes are low emissive in the solution but dramatically showed increase in emission intensity in aggregates form in the THF (tetrahydrofuran) /water system. Dyes are also sensitive to viscosity and showed increased emission intensity in the DCM:PEG 400 system and DMF:PEG 400 system respectively. Dyes 3a and 3b showed higher viscosity sensitivity constant (0.67 and 0.39 respectively) in DMF:PEG 400 system compared to DCM:PEG 400 (0.47 and 0.21 respectively) system which is contrary to the traditional concept of FMRs. Results shows that lowering of twisted intramolecular charge transfer (TICT) and increase in intramolecular charge transfer (ICT) in the excited state could be the reason for such behavior in the aggregate and highly viscous state. This study may provide the new insights into the field of AIEE and FMR research of such hybrid molecules.

  12. FM dyes enter via a store-operated calcium channel and modify calcium signaling of cultured astrocytes

    Science.gov (United States)

    Li, Dongdong; Hérault, Karine; Oheim, Martin; Ropert, Nicole

    2009-01-01

    The amphiphilic fluorescent styryl pyridinium dyes FM1-43 and FM4-64 are used to probe activity-dependent synaptic vesicle cycling in neurons. Cultured astrocytes can internalize FM1-43 and FM4-64 inside vesicles but their uptake is insensitive to the elevation of cytosolic calcium (Ca2+) concentration and the underlying mechanism remains unclear. Here we used total internal reflection fluorescence microscopy and pharmacological tools to study the mechanisms of FM4-64 uptake into cultured astrocytes from mouse neocortex. Our data show that: (i) endocytosis is not a major route for FM4-64 uptake into astrocytes; (ii) FM4-64 enters astrocytes through an aqueous pore and strongly affects Ca2+ homeostasis; (iii) partitioning of FM4-64 into the outer leaflet of the plasma membrane results in a facilitation of store-operated Ca2+ entry (SOCE) channel gating; (iv) FM4-64 permeates and competes with Ca2+ for entry through a SOCE channel; (v) intracellular FM4-64 mobilizes Ca2+ from the endoplasmic reticulum stores, conveying a positive feedback to activate SOCE and to sustain dye uptake into astrocytes. Our study demonstrates that FM dyes are not markers of cycling vesicles in astrocytes and calls for a careful interpretation of FM fluorescence. PMID:20007370

  13. Synthesis and photo-physical properties of fluorescent 1,3,5-triazine styryl derivatives

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    Padalkar Vikas S

    2011-12-01

    Full Text Available Abstract Background Organic fluorophore contains well-defined D-π-A (Donor-π system-Acceptor push-pull system have wide application in the field of NLO, OLED and high tech application. Electron donor diphenyl, triphenyl and carbazole conjugated with electron acceptor terminal through π-system were reported recently for high-tech applications. N,N-Dialkyl substituted 1,3,5-triazine also acts as donor keeping this idea in mind we developed D-π-A styryl dyes. Results Novel "Y"-shaped acceptor-π-donor-π-acceptor type of compounds were synthesized from 4,4'-((6-(4-(diethylaminophenyl-1,3,5-triazine-2,4diylbis(oxy dibenzaldehyde (DIPOD as electron donors and different active methylene compounds as electron acceptors by conventional Knoevenagel condensation reaction. Their photophysical and thermal properties were investigated. Conclusion It was found that the strong electron acceptor-donor chromophoric system of these compounds showed high Stoke's shift and excellent thermal stability. Compounds showed positive solvatofluorism behavior from nonpolar to polar solvent. All compounds have good thermal stability.

  14. Synthesis and antimicrobial activities of new pyridinium and benzimidazolium chlorides.

    Science.gov (United States)

    Pernak, J; Rogoza, J; Mirska, I

    2001-04-01

    A novel class of pyridinium and benzimidazolium chloride has been obtained in high yield. The antimicrobial activities of three homologous series of pyridinium and benzimidazolium chlorides against cocci, rods, fungi and bacillus have been measured. The antimicrobial activities of N,N'-bis[3-(1-alkoxymethyl)pyridinium chloride]methylenediamines, 1-undecyloxymethyl-3-(1-benzimidazolmethylamino)pyridinium, 1-undecyloxymethyl- and 1-dodecyloxymethyl-3-[1(benzotriazol-1-yl)methylamino]pyridinium chlorides exhibited strong activity and wide antibacterial spectra similar to the activity of benzalkonium chloride.

  15. Synthesis and antimicrobial activity of styryl/pyrrolyl/pyrazolyl sulfonylmethyl-1,3,4-oxadiazolyl amines and styryl/pyrrolyl/pyrazolyl sulfonylmethyl-1,3,4-thiadiazolyl amines.

    Science.gov (United States)

    Sravya, G; Yamini, G; Padmavathi, V; Padmaja, A

    2016-10-21

    A new class of mono and bis heterocycles - styryl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines, pyrrolyl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines and pyrazolyl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines were prepared from the synthetic intermediate Z-styrylsulfonylacetic acid adopting simple and well versed synthetic methodologies and studied their antimicrobial activity. Amongst all the tested compounds styryl thiadiazole 5c exhibited promising antimicrobial activity against Pseudomonas aeruginosa and Penicillium chrysogenum. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. Studies on solvatochromic properties of aminophenylstyryl-quinolinum dye, LDS 798, and its application in studying submicron lipid based structure.

    Science.gov (United States)

    Sarkar, Pabak; Luchowski, Rafal; Raut, Sangram; Sabnis, Nirupama; Remaley, Alan; Lacko, Andras G; Thamake, Sanjay; Gryczynski, Zygmunt; Gryczynski, Ignacy

    2010-12-01

    The styryl group of dyes has been used in cellular studies for over 20 years because of their solvatochromic and/or electrochromic properties. Here we report characterization of solubility and solvatochromic properties of a near infra-red styryl dye, styryl 11 or LDS 798. We have extended our studies to small unilamellar vesicles and lipid based nanoparticles and found that solvatochromic properties of this dye used in tandem with fluorescence correlation spectroscopy can be used to efficiently determine the diffusion coefficient and hence the size of the submicron lipid based particles. This technique has the potential to provide essential information about liposomal and vesicular structures and their movement in vitro and in situ. Published by Elsevier B.V.

  17. 4-[(2-Hydroxybenzylamino]pyridinium nitrate

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    Shan Gao

    2012-08-01

    Full Text Available The planes of the aromatic rings in the cation of the title salt, C12H13N2O+·NO3−, are twisted along the –CH2—NH– single bond by 75.3 (1°. In the crystal, the phenol O, amine N and pyridinium N atoms are hydrogen-bond donors to the O atoms of the nitrate counter-ions. These hydrogen bonds lead to the formation of a layer in the crystal.

  18. Development of a no-wash assay for mitochondrial membrane potential using the styryl dye DASPEI

    DEFF Research Database (Denmark)

    Reveles Jensen, Kristian; Rekling, Jens C

    2010-01-01

    Mitochondrial dysfunction is a hallmark of several diseases and may also result from drugs with unwanted side effects on mitochondrial biochemistry. The mitochondrial membrane potential is a good indicator of mitochondrial function. Here, the authors have developed a no-wash mitochondrial membrane...

  19. Cation dynamics in pyridinium nitrate and bis-thiourea pyridinium nitrate inclusion compound studied by {sup 2}H NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Pajzderska, A; Fojud, Z; Goc, R; Wasicki, J [Institute of Physics, A Mickiewicz University, Poznan (Poland)

    2007-04-16

    {sup 2}H NMR (nuclear magnetic resonance) line-shape measurements were performed over a wide temperature range for pyridinium nitrate (d{sub 5}PyH)NO{sub 3} and bis-thiourea pyridinium nitrate inclusion complex T{sub 2}(d{sub 5}PyH)NO{sub 3} in order to compare the dynamics of d{sub 5}-pyridinium cation in both compounds. It was revealed that in both systems the pyridinium cation undergoes reorientations about the axis perpendicular to its plane, among inequivalent potential energy barriers. However, in (d{sub 5}PyH)NO{sub 3} (no phase transition) the population of the deepest minima decreases monotonically up to the melting point, whereas in T{sub 2}(d{sub 5}PyH)NO{sub 3} (two phase transitions) this population decreases rapidly in a transition to the high-temperature phase and its value does not depend on temperature. In bis-thiourea pyridinium nitrate inclusion compound the out-of-plane motion of the cation is also found in the intermediate- and high-temperature phases, and the amplitudes of the motion are equal to 20{sup 0} and 35{sup 0}, respectively. On the basis of the assumptions of these models, it is possible to reproduce the experimental {sup 2}H NMR line shapes in an excellent way.

  20. Pyridinium bis(pyridine-κNtetrakis(thiocyanato-κNferrate(III

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    Sergii I. Shylin

    2013-06-01

    Full Text Available In the title compound, (C5H6N[Fe(NCS4(C5H5N2], the FeIII ion is coordinated by four thiocyanate N atoms and two pyridine N atoms in a trans arrangement, forming an FeN6 polyhedron with a slightly distorted octahedral geometry. Charge balance is achieved by one pyridinium cation bound to the complex anion via N—H...S hydrogen bonding. The asymmetric unit consists of one FeIII cation, four thiocyanate anions, two coordinated pyridine molecules and one pyridinium cation. The structure exhibits π–π interactions between pyridine rings [centroid–centroid distances = 3.7267 (2, 3.7811 (2 and 3.8924 (2 Å]. The N atom and a neighboring C atom of the pyridinium cation are statistically disordered with an occupancy ratio of 0.58 (2:0.42 (2.

  1. Optical Biomedical Diagnostics: Sensors with Optical Response Based on Two-Photon Excited Luminescent Dyes for Biomolecules Detection

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    V. M. Yashchuk

    2008-01-01

    Full Text Available The spectral properties of novel styryl dyes developed for the biomacromolecules (such as DNA detection and imaging were investigated. The energy structures of dye molecules were examined. The spectral data prove that dyes aggregate and interact with DNA. The essential increase of the fluorescence intensity of dyes in the presence of DNA was observed. The photostability and phototoxic influence on the DNA of several styryl dyes were studied by analyzing absorption, fluorescence, and phosphorescence spectra of these dyes and dye-DNA systems. Changes of the optical density value of dye-DNA solutions caused by the irradiation were fixed in the DNA and dye absorption wavelength regions. Fluorescence emission of dye-DNA complexes upon two-photon excitation at wavelength 1064 nm with the 20-nanosecond pulsed YAG:Nd3+ laser and at 840 nm with the 90 famtosecond pulsed Ti:sapphire laser was registered. The values of two-photon absorption cross-sections of dye-DNA complexes were evaluated.

  2. The cytotoxic styryl lactone goniothalamin is an inhibitor of nucleocytoplasmic transport.

    Science.gov (United States)

    Wach, Jean-Yves; Güttinger, Stephan; Kutay, Ulrike; Gademann, Karl

    2010-05-01

    An in vivo nuclear export assay (immunostaining of Rio2 in HeLa cells) demonstrated that (R)-goniothalamin is an inhibitor of nucleocytoplasmic transport above 500 nM, which was rationalized also by molecular modeling. The cytotoxic styryl lactone natural product was prepared via an enantioselective Cr(III) catalyzed hetero Diels-Alder reaction and a Sonogashira coupling. A series of analogs was synthesized and only the oxidized goniothalamin derivative featuring an alkyne spacer was found active. Unsaturated lactones of natural origin other than leptomycin (LMB) are thus suggested to operate via a similar mechanism targeting the CRM1 nuclear receptor. 2010 Elsevier Ltd. All rights reserved.

  3. Graft polymerization of styryl bisphosphonate monomer onto polypropylene films for inhibition of biofilm formation.

    Science.gov (United States)

    Steinmetz, Hanna P; Rudnick-Glick, Safra; Natan, Michal; Banin, Ehud; Margel, Shlomo

    2016-11-01

    There has been increased concern during the past few decades over the role bacterial biofilms play in causing a variety of health problems, especially since they exhibit a high degree of resistance to antibiotics and are able to survive in hostile environments. Biofilms consist of bacterial aggregates enveloped by a self-produced matrix attached to the surface. Ca(2+) ions promote the formation of biofilms, and enhance their stability, viscosity, and strength. Bisphosphonates exhibit a high affinity for Ca(2+) ions, and may inhibit the formation of biofilms by acting as sequestering agents for Ca(2+) ions. Although the antibacterial activity of bisphosphonates is well known, research into their anti-biofilm behavior is still in its early stages. In this study, we describe the synthesis of a new thin coating composed of poly(styryl bisphosphonate) grafted onto oxidized polypropylene films for anti-biofilm applications. This grafting process was performed by graft polymerization of styryl bisphosphonate vinylic monomer onto O2 plasma-treated polypropylene films. The surface modification of the polypropylene films was confirmed using surface measurements, including X-ray photoelectron spectroscopy, atomic force microscopy, and water contact angle goniometry. Significant inhibition of biofilm formation was achieved for both Gram-negative and Gram-positive bacteria. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Synthesis and bactericidal properties of pyridinium chlorides with alkylthiomethyl and alkoxymethyl hydrophobic groups.

    Science.gov (United States)

    Weglewski, J; Pernak, J; Krysinski, J

    1991-01-01

    The products of a reaction between 3-ethoxymethylpyridine and chloromethylalkyl ether or sulfide were proven to be 1-[(alkylthio)-methyl]-3-[(ethoxy)methyl]pyridinium or 1-[(alkoxy)methyl]-3-[(ethoxy)-methyl]pyridinium chlorides. Bacteriostatic properties of the obtained chlorides against 13 different microbial strains representing cocci, rods, fungi, and bacilli were studied. The MICs were measured by serial dilution. All studied chlorides showed bacteriostatic properties. Particularly high activity against microbes was shown by 1-[(dodecylthio)-methyl]-3-[(ethoxy)methyl]pyridinium and 3-[(ethoxy)methyl]-1-[(tetradecylthio)methyl]pyridinium chlorides.

  5. Epoxy nanocomposites based on high temperature pyridinium-modified clays.

    Science.gov (United States)

    Zhang, Qingxin; Naito, Kimiyoshi; Qi, Ben; Kagawa, Yutaka

    2009-01-01

    Polymer/clay nanocomposites are generally fabricated by thermal curing or melt compounding at elevated temperatures, however the thermal stability of common alkyl ammonium treated clays is poor and decomposition occurs inevitably during high temperature processing. In this study, we modified clays with an aromatic pyridinium salt. Thermogravimetric analysis (TGA) showed that the onset degradation temperature (Td(onset)) and maximum decomposition temperature (Td(max)) of the pyridinium treatment clays was up to 310 and 457 degrees C respectively implying high thermal stability. The thermal decomposition behaviour of the pyridinium modified clays was discussed. A series of epoxy/clay nanocomposites were synthesized using a diglycidyl ether of bisphenol A (DGEBA) epoxy and diethyltoluene diamine (DETDA). The morphology of epoxy/clay nanocomposites was characterized with wide angle X-ray diffraction (WAXD) and transmission electron microscope (TEM), and intercalated structures were observed. The storage modulus of epoxy was increased but glass transition temperature was decreased with clay incorporation. The effects of clays on glass transition temperature (Tg) of epoxy were also discussed.

  6. Single-Step Synthesis of Styryl Phosphonic Acids via Palladium-Catalyzed Heck Coupling of Vinyl Phosphonic Acid with Aryl Halides

    Energy Technology Data Exchange (ETDEWEB)

    Sellinger, Alan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McNichols, Brett W. [Colorado School of Mines; United States Air Force Academy; Koubek, Joshua T. [Colorado School of Mines

    2017-10-27

    We have developed a single step palladium-catalyzed Heck coupling of aryl halides with vinyl phosphonic acid to produce functionalized (E)-styryl phosphonic acids. This pathway utilizes a variety of commercially available aryl halides, vinyl phosphonic acid and Pd(P(tBu)3)2 as catalyst. These conditions produce a wide range of styryl phosphonic acids with high purities and good to excellent yields (31-80%).

  7. Investigation of the Pyridinium Ylide—Alkyne Cycloaddition as a Fluorogenic Coupling Reaction

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    Simon Bonte

    2016-03-01

    Full Text Available The cycloaddition of pyridinium ylides with alkynes was investigated under mild conditions. A series of 13 pyridinium salts was prepared by alkylation of 4-substituted pyridines. Their reactivity with propiolic ester or amide in various reaction conditions (different temperatures, solvents, added bases was studied, and 11 indolizines, with three points of structural variation, were, thus, isolated and characterized. The highest yields were obtained when electron-withdrawing groups were present on both the pyridinium ylide, generated in situ from the corresponding pyridinium salt, and the alkyne (X, Z = ester, amide, CN, carbonyl, etc.. Electron-withdrawing substituents, lowering the acid dissociation constant (pKa of the pyridinium salts, allow the cycloaddition to proceed at pH 7.5 in aqueous buffers at room temperature.

  8. 3-Carboxy-5-(pyridinium-4-ylbenzoate: a redetermination

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    Shi-Jie Li

    2011-06-01

    Full Text Available The title compound, C13H9NO4, crystallizes in a zwitterionic form with the pyridine N atom protonated and the carboxyl OH group deprotonated. The benzene and pyridinium rings are inclined with a dihedral angle of 31.42 (14° between them. A previous report of this stucture claims, we believe incorrectly, that neither of the carboxylate groups is deprotonated [Zhang et al. (2010. Acta Cryst. E66, o2928–o2928]. In the crystal, intermolecular O—H...O, N—H...O and weak C—H...O hydrogen-bonding interactions link adjacent molecules into a three-dimensional supramolecular network.

  9. 5-(2-amimo-4-styryl pyrimidine-4-yl-4-methoxybenzofuran-6-ol

    Directory of Open Access Journals (Sweden)

    Atteyat A Labib

    2013-05-01

    Full Text Available This study describes the organic synthesis of 5-(2-amimo-4-styryl pyrimidine-4-yl-4-methoxy benzofuran-6-ol (SPBF as an example of a benzofuran derivative used as a new series of amyloid imaging agents. These benzofuran derivatives may be useful amyloid imaging agents for detecting B-amyloid plagues in the brain of Alzheimer’s disease. The precursor is 1-[6-hydroxy-4-methoxybenzofuran-5-yl]-phenyl butadiene ketone, which react with guanidine hydrochloride. The purification process was done via crystallization using solvent ethanol. The overall yield was 75% and the structure of the synthesized compound was confirmed by correct analytical and spectral data. Also, The synthesized compound was labeled with radioactive iodine -125 via electrophilic substitution reaction, in the presence of iodogen as an oxidizing agent, the labeling process was carried out at 95oC for 20min. The radiochemical yield was determined by using a thin layer chromatography and the yield was equal to 80%. Preliminary an in-vivo study examined normal mice after intravenous injection through the tail vein and the data showed the labeling compound was quickly cleared from most body organs. The radioiodinated compound showed high brain uptake.The results of this study suggest that radioiodinated (SPBF may be useful as a brain imaging agents.

  10. Synthesis, characterization and properties of yellow-light-emitting polyethers containing bis(styryl)anthracene units

    Energy Technology Data Exchange (ETDEWEB)

    Gioti, M., E-mail: mgiot@physics.auth.gr; Pitsalidis, C., E-mail: mgiot@physics.auth.gr; Tzounis, L.; Logothetidis, S., E-mail: logot@auth.gr [Laboratory for Thin Films-Nanosystems and Nanometrology (LTFN), Physics Department, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); Andreopoulou, A. K.; Kallitsis, J. K. [Department of Chemistry, University of Patras, University Campus, Rio-Patras GR26504, Greece and Foundation for Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Platani Str., Patras GR26504 (Greece); Mparmpoutsis, E. [Department of Chemistry, University of Patras, University Campus, Rio-Patras GR26504 (Greece)

    2015-02-17

    Aromatic aliphatic polyethers containing bis(styryl)anthracene units in the main chain separated by flexible spacer of 11 (AND52) or 12 (AND53) methylene units, were synthesized and characterized aiming to be applied as emitting materials in polymer light emitting diode (PLED) devices. The polymers are soluble in common organic solvents and have average molecular weight of about 15kDa. Differentiations owing to an odd-even number of methylene units (χ=11 vs χ=12) are observed in their optical properties in solid state. Thin films as well as PLED devices were fabricated via conventional spin-coating process. Initially, various parameters have been investigated concerning the solubility of the polymers, the effect of film thickness on the electrical properties, and their thermal stability. The optical properties of the two polymers were investigated by NIR-Vis-far UV spectroscopic ellipsometry (SE). The accurate determination of the thickness and the optical constants (refractive index and dielectric function as a function of wavelength) were derived. These provide substantial insights into the final design of the optimum final multi-layer structure of the PLEDs, if we take into account that the external quantum efficiency (EQE) of electroluminescence (EL) strongly depends on the optical interference of the beams of emitted light that have been multiply reflected from the layer interfaces. The morphological characterization of the AND52 and AND53 polymeric thin films was carried out using atomic force microscopy (AFM), while current density-voltage (J-V) characteristics of the devices were studied by electrical measurements. The single PLED devices were switched on at relatively low operation voltages, showing the potential as backplanes for active matrix PLED applications. In this perspective, it can be assumed that further studies of the presented materials will enable the development of flexible PLEDs with the possibility to scale up their dimensions for bigger

  11. Density functional theory study on the ionic liquid pyridinium hydrogen sulfate

    Science.gov (United States)

    Tankov, Ivaylo; Yankova, Rumyana; Genieva, Svetlana; Mitkova, Magdalena; Stratiev, Dicho

    2017-07-01

    The geometry, electronic structure and chemical reactivity of a pyridinium-based ionic liquid, pyridinium hydrogen sulfate ([H-Pyr]+[HSO4]-), have been discussed on the basis of quantum chemical density functional theory calculations using B3LYP/6-311+G(d,p) and B3LYP/6-311++G(2d,2p) approaches. The calculations indicated that [H-Pyr]+[HSO4]- exists in the form of an ion pair. A large electropositive potential was found on the pyridinium ring, while the regions of a negative electrostatic potential is linked with the lone pair of electronegative oxygen atoms in hydrogen sulfate anion ([HSO4]-). Electron transfer both within the anion, and between the anion and cation of an ion pair were described using natural bond orbital theory. The energy values of -7.1375 and -2.8801 eV were related to HOMO and LUMO orbitals, respectively.

  12. Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts

    Directory of Open Access Journals (Sweden)

    Mostafa Kiamehr

    2013-06-01

    Full Text Available The cyclization of cyclohexane-1,3-diones with various substituted pyridinium salts afforded functionalized 8-oxa-10-aza-tricyclo[7.3.1.02,7]trideca-2(7,11-dienes. The reaction proceeds by regioselective attack of the central carbon atom of the 1,3-dicarbonyl unit to 4-position of the pyridinium salt and subsequent cyclization by base-assisted proton migration and nucleophilic addition of the oxygen atom to the 2-position, as was elucidated by DFT computations. Fairly extensive screening of bases and additives revealed that the presence of potassium cations is essential for formation of the product.

  13. Synthesis and crystal structure of a new pyridinium bromide salt: 4-methyl-1-(3-phen-oxy-prop-yl)pyridinium bromide.

    Science.gov (United States)

    Said, Musa A; Aouad, Mohamed R; Hughes, David L; Almehmadi, Meshal A; Messali, Mouslim

    2017-12-01

    In the cation of the title mol-ecular salt, C 15 H 18 NO + ·Br - , the pyridinium and phenyl rings are inclined to one another by 11.80 (8)°. In the crystal, the Br - anion is linked to the cation by a C-H⋯Br hydrogen bond. The cations stack along the b -axis direction and are linked by further C-H⋯Br inter-actions, and offset π-π inter-actions [inter-centroid distances = 3.5733 (19) and 3.8457 (19) Å], forming slabs parallel to the ab plane. The effects of the C-H⋯ X - inter-action on the NMR signals of the ortho- and meta- pyridinium protons in a series of related ionic liquids, viz . 4-methyl-1-(4-phen-oxy-but-yl)pyridin-1-ium salts, are reported and discussed.

  14. A Mixed Ligand Approach for the Asymmetric Hydrogenation of 2-Substituted Pyridinium Salts

    NARCIS (Netherlands)

    Renom-Carrasco, Marc; Gajewski, Piotr; Pignataro, Luca; de Vries, Johannes G.; Piarulli, Umberto; Gennari, Cesare; Lefort, Laurent

    2016-01-01

    Herein we describe a new methodology for the asymmetric hydrogenation (AH) of 2-substituted pyridinium salts. An iridium catalyst based on a mixture of a chiral monodentate phosphoramidite and an achiral phosphine was shown to hydrogenate N-benzyl-2-arylpyiridinium bromides to the corresponding

  15. In vivo evidence of the targeting of cartilaginous tissue by pyridinium functionalized nanoparticles.

    Science.gov (United States)

    Morlieras, Jessica; Chezal, Jean-Michel; Miot-Noirault, Elizabeth; Vidal, Aurélien; Besse, Sophie; Kryza, David; Truillet, Charles; Mignot, Anna; Antoine, Rodolphe; Dugourd, Philippe; Redini, Françoise; Sancey, Lucie; Lux, François; Perriat, Pascal; Janier, Marc; Tillement, Olivier

    2013-04-14

    Ultrasmall gadolinium based particles have been functionalized with positively charged pyridinium quaternary ammonium and labelled with (111)In. Evidence of their active targeting properties towards proteoglycans has been demonstrated in vivo after intravenous injection into rats opening thus a route to cancer imaging and therapy.

  16. Pyridinium hydrobromide perbromide: a versatile catalyst for aziridination of olefins using Chloramine-T.

    Science.gov (United States)

    Ali, S I; Nikalje, M D; Sudalai, A

    1999-09-09

    [reaction: see text] Pyridinium hydrobromide perbromide (Py x HBr3) catalyzes effectively the aziridination of electron-deficient as well as electron-rich olefins using Chloramine-T (N-chloro-N-sodio-p-toluenesulfonamide) as a nitrogen source to afford the corresponding aziridines in moderate to good yields.

  17. Dye lasers

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-10-31

    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.

  18. Syntheses and photodynamic activity of some glucose-conjugated BODIPY dyes.

    Science.gov (United States)

    Shivran, Neelam; Tyagi, Mrityunjay; Mula, Soumyaditya; Gupta, Pooja; Saha, Bhaskar; Patro, Birija S; Chattopadhyay, Subrata

    2016-10-21

    The syntheses of three water-soluble glucose-conjugated BODIPY dyes with different wavelength emissions and studies of their photodynamic therapeutic (PDT) action on human lung cancer A549 cell line are disclosed. Amongst the chosen compounds, the BODIPY dye 4 possessing a glycosylated styryl moiety at the C-3 position showed best PDT property against the A549 cell line. In particular, it induced reactive oxygen species-mediated caspase-8/caspase-3-dependent apoptosis as revealed from the increased sub G1 cell population and changes in cell morphology. These results along with its localization in the endoplasmic reticulum, as revealed by confocal microscopy suggested that mitochondria may not be directly involved in the photo-cytotoxicity of 4. Compound 4 did not induce any dark toxicity to the A549 cells, and was non-toxic to normal lung cells. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Unusual emission properties of the selected organosilicon compounds containing a styryl-carbazole chromophore: inversion of the singlet excited states.

    Science.gov (United States)

    Rachuta, K; Bayda, M; Majchrzak, M; Koput, J; Marciniak, B

    2017-05-10

    The spectroscopic and photophysical properties of silicon-containing styryl-carbazole were investigated in various solvents, and the results were analyzed with reference to its carbon derivatives. In n-hexane, both the silicon- and the carbon-containing compounds had very similar emission properties. In acetonitrile, the emission properties remained the same for the C-compound but changed significantly for the Si-compounds. In particular, the fluorescence spectra of the latter were red-shifted, and their radiative rate constants were even 7 times larger than in n-hexane, which suggested that the emissive states of the silicon-containing compounds were different in these two solvents. DFT calculations using the CAM-B3LYP functional showed that the emissive state of the C-compound involves the LUMO+1 orbital regardless of the medium. In contrast, for the Si-compound, changing the medium from n-hexane to acetonitrile resulted in the inversion of the emissive states from an excited state involving the LUMO+1 orbital (the dipole moment μ = 4.2 D) to an excited state involving the LUMO orbital (μ = 8.9 D).

  20. Textile dyes

    OpenAIRE

    Guaratini, Cláudia C. I. [UNESP; Zanoni, Maria Valnice Boldrin [UNESP

    2000-01-01

    A dye is a colored substance used to impart permanent color to other substances. Its most important use is in coloring textile fibers and fabrics. The removal of colour from dyehouse waste waters is currently a major problem in the textile sector. This paper provides an overview of the treatment technologies that can currently be used by the textile processor and the developments over the past decade with respect to the toxicological and ecotoxicological properties of synthetic organic dyes.

  1. Supramolecular helical nanofibers assembled from a pyridinium-functionalized methyl glycyrrhetate amphiphile

    Science.gov (United States)

    Gao, Yuxia; Hao, Jie; Wu, Jindan; Zhang, Xun; Hu, Jun; Ju, Yong

    2015-08-01

    A glycyrrhetate-containing amphiphile, MGP (1-[2-(methyl glycyrrhetate)-2-oxoethyl]pyridinium bromide), has been synthesized, and found to assemble into supramolecular helical nanofibers in chloroform/aromatic solvents, which are primarily driven by π-π stacking, van der Waals forces, and hydrophobic interactions. During the assembly process, MGP stacked into J-aggregates resulting in the sequestration of the hydrophilic pyridinium cation within the interior with the concomitant projection of its hydrophobic skeleton on the outside surface. Ultimately, this protrusion generated a staggered angle due to the steric hindrance between stacked molecules. This staggered angle further led to molecular misalignments and the formation of helical fibrils, which could twist with each other to fabricate larger helical fibers. Consequently, a gel was formed by intertwining these nanofibers into three-dimensional networks. Using this strategy, we found that other triterpenoid-tailored pyridinium amphiphiles are also potential scaffolds for supramolecular helical structures. This work provides a facile approach for the fabrication of supramolecular macroscopic chiral nanostructures that originate from natural products.A glycyrrhetate-containing amphiphile, MGP (1-[2-(methyl glycyrrhetate)-2-oxoethyl]pyridinium bromide), has been synthesized, and found to assemble into supramolecular helical nanofibers in chloroform/aromatic solvents, which are primarily driven by π-π stacking, van der Waals forces, and hydrophobic interactions. During the assembly process, MGP stacked into J-aggregates resulting in the sequestration of the hydrophilic pyridinium cation within the interior with the concomitant projection of its hydrophobic skeleton on the outside surface. Ultimately, this protrusion generated a staggered angle due to the steric hindrance between stacked molecules. This staggered angle further led to molecular misalignments and the formation of helical fibrils, which could

  2. Atomistic Force Field for Pyridinium-Based Ionic Liquids: Reliable Transport Properties

    DEFF Research Database (Denmark)

    Voroshylova, I. V.; Chaban, V. V.

    2014-01-01

    Reliable force field (FF) is a central issue in successful prediction of physical chemical properties via computer simulations. This work introduces refined FF parameters for six popular ionic liquids (ILs) of the pyridinium family (butylpyridinium tetrafluoroborate, bis(trifluoromethanesulfonyl)......Reliable force field (FF) is a central issue in successful prediction of physical chemical properties via computer simulations. This work introduces refined FF parameters for six popular ionic liquids (ILs) of the pyridinium family (butylpyridinium tetrafluoroborate, bis...... and elevated temperature. The developed atomistic models provide a systematic refinement upon the well-known Canongia LopesPadua (CL&P) FF. Together with the original CL&P parameters the present models foster a computational investigation of ionic liquids....

  3. Synthesis and biological evaluation of pyridinium-functionalized carbazole derivatives as promising antibacterial agents.

    Science.gov (United States)

    Wang, Pei-Yi; Fang, He-Shu; Shao, Wu-Bin; Zhou, Jian; Chen, Zhuo; Song, Bao-An; Yang, Song

    2017-09-15

    Various pyridinium-functionalized carbazole derivatives were constructed by coupling the key fragments of carbazole skeleton and pyridinium nucleus in a single molecular architecture. Antibacterial bioassays revealed that some of the title compounds displayed impressive bioactivities against plant pathogens such as Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri with minimal EC50 values of up to 0.4, 0.3, and 0.3mg/L, respectively. These bioactivities were achieved by systematically tuning and optimizing bridging linker, alkyl length of the tailor, and substituents on the carbazole scaffold. Compared with the bioactivity of the lead compound (AP-10), antibacterial efficacy dramatically increased by approximately 13-, 104- and 21-fold. This finding suggested that these compounds can serve as new lead compounds in research on antibacterial chemotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Synthesis and anti-microbial activities of some pyridinium salts with alkoxymethyl hydrophobic group.

    Science.gov (United States)

    Pernak, J; Kalewska, J; Ksycińska, H; Cybulski, J

    2001-01-01

    A novel class of functionalized cationic surfactant has been obtained. The work-up procedure of synthesis is very simple, the yield is high and the pyridinium salts with alkoxymethyl hydrophobic group are easily purified. All the salts examined showed anti-microbial activities. Some of them exhibited strong activity and wide anti-bacterial spectra similar to the activity of benzalkonium chloride. The relationship between chemical structure and anti-microbial activity was analysed by the QSAR method.

  5. Antithrombotic effects of pyridinium compounds formed from trigonelline upon coffee roasting.

    Science.gov (United States)

    Kalaska, Bartlomiej; Piotrowski, Lukasz; Leszczynska, Agnieszka; Michalowski, Bartosz; Kramkowski, Karol; Kaminski, Tomasz; Adamus, Jan; Marcinek, Andrzej; Gebicki, Jerzy; Mogielnicki, Andrzej; Buczko, Wlodzimierz

    2014-04-02

    Coffee may exert a preventive effect on arterial thrombosis. Trigonelline is one of the most abundant compounds in coffee that undergoes pyrolysis upon roasting of coffee beans. The aim of the present study was to identify pyridinium compounds formed upon trigonelline pyrolysis and coffee roasting and to investigate the effect of three of them, i.e., 1-methylpyridine and 1,3- and 1,4-dimethylpyridine, on experimentally induced arterial thrombosis in rats. 1,3- and 1,4-dimethylpyridine but not 1-methylpyridine inhibited arterial thrombus formation. 1,3-Dimethylpyridine inhibited platelet aggregation and reduced fibrin formation in platelet-rich plasma, whereas 1,4-dimethylpyridine increased the plasma level of 6-keto-PGF1α. 1,4-Dimethylpyridine slightly increased rat tissue plasminogen activator plasma activity. In summary, we demonstrated that pyridinium compounds display mild antithrombotic properties due to stimulation by prostacyclin release (1,4-dimethylpyridine) and inhibition of platelet aggregation (1,3-dimethylpyridine). Those pyridinium compounds may, to some extent, be responsible for the beneficial effects of coffee drinking.

  6. Effect of N-pyridinium positions of quaternized chitosan on transfection efficiency in gene delivery system.

    Science.gov (United States)

    Sajomsang, Warayuth; Gonil, Pattarapond; Ruktanonchai, Uracha Rungsardthong; Petchsangsai, Maleenart; Opanasopit, Praneet; Puttipipatkhachorn, Satit

    2014-04-15

    Methylated N-pyridylmethyl chitosan chlorides (M-PyMeChCs) with a similar total degree of quaternization (DQT) and molecular weight but different N-pyridinium positions were synthesized by reductive amination and methylation, respectively. The effect of N-pyridinium positions on transfection efficiency and cytotoxicity was investigated in human hepatoma (Huh7) cell lines. The results revealed that M-PyMeChCs are able to form a complete complex formation with DNA since there is an N/P ratio of 5. The particle sizes of M-PyMeChCs/DNA nanopolyplexes were approximately 300 nm and indicated a positive charge. The morphology of these nanopolyplexes was found to be in a spherical shape which was investigated by using the transmission electron microscopy (TEM). The M4-PyMeChC/DNA nanopolyplexes showed highest in vitro transfection efficiency in Huh7 cells at N/P ratio of 20 compared to M2-PyMeChC/DNA and M3-PyMeChC/DNA nanopolyplexes. In comparison to M3-PyMeChC/DNA nanopolyplexes, M2-PyMeChC/DNA and M4-PyMeChC/DNA nanopolyplexes showed lower cytotoxicity in Huh7 cells. Our result demonstrated that N-pyridinium positions of M-PyMeChCs are related to transfection efficiency and cytotoxicity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. The interactions between lipase and pyridinium ligands investigated by electrochemical and spectrophotometric methods

    Directory of Open Access Journals (Sweden)

    Simona Patriche

    2016-04-01

    Full Text Available The interaction between pyridinium ligands derived from 4,4’-bipyridine (N,N’-bis(p-bromophenacyl-4,4’-bipyridinium dibromide – Lr and (N,N’-bis(p-bromophenacyl-1,2-bis (4-pyridyl ethane dibromide – Lm with lipase enzyme was evaluated. The stability of the pyridinium ligands, having an essential role in biological systems, in 0.1 M KNO3 as supporting electrolyte is influenced by the lipase concentration added. The pH and conductometry measurements in aqueous solution suggest a rapid ionic exchange process. The behavior of pyridinium ligands in the presence of lipase is investigated by cyclic voltammetry and UV/Vis spectroscopy, which indicated bindings and changes from the interaction between them. The voltammograms recorded on the glassy carbon electrode showed a more intense electronic transfer for the Lr interaction with lipase compared to Lm, which is due to the absence of mobile ethylene groups from Lr structure.

  8. The p-T phase diagram for ferroelectric bis-thiourea pyridinium nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Bilski, P. [Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland); Czarnecki, P., E-mail: pczarnec@amu.edu.pl [Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland); Lewicki, S.; Wasicki, J. [Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)

    2011-08-15

    Highlights: > Bis-thiourea pyridinium nitrate has been studied at high pressures up to 1 GPa. > p-T phase diagram has been obtained by NMR and dielectric method. > The triple point is observed in p-T diagram. > The continuous phase transition is changed to discontinuous at the pressure 450 Mpa. - Abstract: The effect of temperature and pressure on physical properties of the ferroelectric bis-thiourea pyridinium nitrate inclusion compound has been studied by dielectric spectroscopy and nuclear magnetic resonance (NMR). At ambient pressure the ferroparaelectric phase transition observed at T{sub 2} = 216 K is continuous in contrast to the nonferroelectric phase transition observed at T{sub 1} = 273 K. Under small pressures, the temperatures of the phase transitions T{sub 1} and T{sub 2} increase with increasing pressure. Starting from about 250 MPa, T{sub 1} temperature decreases with increasing pressure, while T{sub 2} temperature increases with increasing pressure. At 450 MPa and 245 K a triple point is observed. Bis-thiourea pyridinium nitrate undergoes a continuous phase transition from the ferroelectric to paraelectric phase under 450 MPa, while above this pressure the phase transition from the ferroelectric to paraelectric phase is discontinuous. The change in the phase transition character is related to the crystallographic change in the group-subgroup relation between the ferro- and paraelectric phases taking place with increasing pressure.

  9. Synthesis and crystal structure of a new pyridinium bromide salt: 4-methyl-1-(3-phen­oxy­prop­yl)pyridinium bromide

    Science.gov (United States)

    Said, Musa A.; Aouad, Mohamed R.; Hughes, David L.; Almehmadi, Meshal A.; Messali, Mouslim

    2017-01-01

    In the cation of the title mol­ecular salt, C15H18NO+·Br−, the pyridinium and phenyl rings are inclined to one another by 11.80 (8)°. In the crystal, the Br− anion is linked to the cation by a C—H⋯Br hydrogen bond. The cations stack along the b-axis direction and are linked by further C—H⋯Br inter­actions, and offset π–π inter­actions [inter­centroid distances = 3.5733 (19) and 3.8457 (19) Å], forming slabs parallel to the ab plane. The effects of the C—H⋯X − inter­action on the NMR signals of the ortho- and meta-pyridinium protons in a series of related ionic liquids, viz. 4-methyl-1-(4-phen­oxy­but­yl)pyridin-1-ium salts, are reported and discussed. PMID:29250397

  10. Locally Excited State-Charge Transfer State Coupled Dyes as Optically Responsive Neuron Firing Probes.

    Science.gov (United States)

    Sirbu, Dumitru; Butcher, John B; Waddell, Paul G; Andras, Peter; Benniston, Andrew C

    2017-10-17

    A selection of NIR-optically responsive neuron probes was produced comprising of a donor julolidyl group connected to a BODIPY core and several different styryl and vinylpyridinyl derived acceptor moieties. The strength of the donor-acceptor interaction was systematically modulated by altering the electron withdrawing nature of the aryl unit. The fluorescence quantum yield was observed to decrease as the electron withdrawing effect of the aryl subunit increased in line with changes of the Hammett parameter. The effectiveness of these fluorophores as optically responsive dyes for neuronal imaging was assessed by measuring the toxicity and signal-to-noise ratio (SNR) of each dye. A great improvement of SNR was obtained when compared to the first-generation BODIPY-based voltage sensitive dyes with concomitant toxicity decrease. The mechanism for the optical response is disparate from conventional cyanine-based dyes, opening up a new way to produce effective voltage sensitive dyes that respond well into the NIR region. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Hair Dye

    African Journals Online (AJOL)

    cosmetics, temporary tattoos, photographic development and lithography plates, photocopying and printing inks, black rubber, oils, greases and gasoline [2]. PPD is the most common constituent of hair dye formulations. It is often the key ingredient but can also be used for color enhancement. PPD is commonly used.

  12. Laser Dyes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 9. Laser Dyes. G S Shankarling K J Jarag. General Article Volume 15 Issue 9 September ... Author Affiliations. G S Shankarling1 K J Jarag1. Dyestuff Technology, Department Institute of Chemical Technology, Matunga Mumbai 400 019, India.

  13. Waterless Textile Dyeing

    OpenAIRE

    ODABAŞOĞLU, Hakkı Yasin; AVİNÇ, Osman Ozan; YAVAŞ, Arzu

    2013-01-01

    Supercritical carbon dioxide (scCO), having liquid-like densities, hereby provides hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can lead to shorter dyeing durations compared to conventional water dyeing process. Supercritical carbon dioxide dyeing, a novel dyeing process, is an anhydrous dyeing and this process involves the use of less energy and chemicals than conventional water dyeing processes resulting in a potential of up to 50% low...

  14. Nano-dyeing

    Directory of Open Access Journals (Sweden)

    Ning Cui-Juan

    2016-01-01

    Full Text Available Dyeing nanofibers is a frontier of both modern textile engineering and nanotechnology. This paper suggest a feasible method for dyeing nanofibers with a natural red (Roselle Calyx by bubble electrospinning. Reactive dye (Red S3B and acid dye (Red 2B were also used in the experiment for comparison. The dyeing process was finished during the spinning process.

  15. Linear and nonlinear optical properties of two-photon absorption dye doped linear copolymer

    Science.gov (United States)

    Wang, D.; Zhou, G. Y.; Ren, Y.; Yu, X. Q.; Cheng, X. F.; Yang, S. J.; Xu, X. G.; Shao, Z. S.; Jiang, M. H.

    2002-02-01

    2-hydroxyethyl methacrylate (abbreviated as HEMA) and acrylonitrile have been used as the monomers to form a trans-4-[p-(N-hydroxyethyl-N-methylamino)styryl]-N-methylpyridinium p-toluene sulfonate (abbreviated as HMASPS) doped linear copolymer. The spectra of one and two-photon excited fluorescence and two-photon pumped superradiance and two-photon pumped lasing of the polymer all shifted to short wavelengths compared with the solution sample of the dye. The copolymer shows much longer one- and two-photon excited fluorescence lifetimes of nanoseconds. When pumped by the picosecond Nd:YAG laser, the superradiance and lasing can be simultaneously obtained. The maximum two-photon pumped lasing conversion efficiency is 3.3%. The place of the maximum upconversion efficiency of the copolymer does not coincide with that of the maximum nonlinear absorption.

  16. Oxidation of phenyl alanine by pyridinium chlorochromate in acidic DMF–water medium: A kinetic study

    Directory of Open Access Journals (Sweden)

    B.L. Hiran

    2016-11-01

    Full Text Available The kinetics of oxidation of phenyl alanine by pyridinium chlorochromate in DMF–water (70:30% mixture in presence of perchloric acid leads to the formation of corresponding aldehyde. The reaction is of first order each in [PCC], [HClO4] and [AA]. Michaelis–Menten type kinetics was observed with phenyl alanine. The reaction rates were determined at different temperatures [25, 30, 35, 40, 45, 50 °C] and the activation parameters were calculated. The reaction does not induce polymerization of acrylonitrile. With an increase in the amount of DMF in its aqueous mixture, the rate increases. A suitable mechanism for the reaction was postulated.

  17. Correlation of electrochemical properties of expanded pyridinium compounds with their single molecule conductance

    Czech Academy of Sciences Publication Activity Database

    Nováková Lachmanová, Štěpánka; Šebera, Jakub; Kolivoška, Viliam; Gasior, Jindřich; Mészáros, G.; Dupeyre, G.; Lainé, P. P.; Hromadová, Magdaléna

    2018-01-01

    Roč. 301, FEB 2018 (2018), s. 301-311 ISSN 0013-4686 R&D Projects: GA ČR GA18-04682S; GA ČR GJ16-07460Y; GA MŠk(CZ) 7AMB15FR027 Grant - others:AV ČR(CZ) MTA-16-02 Program:Bilaterální spolupráce Institutional support: RVO:61388955 Keywords : Expanded pyridinium * Electron transfer and electron transport * Single molecule conductance Subject RIV: CG - Electrochemistry Impact factor: 4.798, year: 2016

  18. Hair dye poisoning

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002703.htm Hair dye poisoning To use the sharing features on this page, please enable JavaScript. Hair dye poisoning occurs when someone swallows dye or tint ...

  19. Antimicrobial activities of pyridinium-tailored pyrazoles bearing 1,3,4-oxadiazole scaffolds

    Directory of Open Access Journals (Sweden)

    Lei Zhou

    2017-11-01

    Full Text Available Herein, a series of pyridinium-tailored 5-trifluoromethylpyrazoles containing 1,3,4-oxadiazole moieties were constructed through coupling key pharmaceutical fragments of pyridinium, pyrazole, and 1,3,4-oxadiazole scaffolds in single molecular architecture. Antimicrobial results suggested that this kind of compounds exhibited significant activities against three types of pathogenic bacteria and six fungal strains in vitro. The minimal EC50 values of designed compounds against Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri could reach to 0.467, 1.04, and 0.600 μg/mL, respectively, through tuning and optimizing N-substituents, bridging atom, and alkyl length of the tailor. Antifungal assays revealed that all title molecules possessed considerable activity against Botrytis cinerea with the minimal EC50 value up to 2.71 μg/mL; and compounds I-8, I-10, I-12, II-12, and IV-12 showed the strongest growth suppression toward Rhizoctonia solani with EC50 values ranging from 10.2 to 24.0 μg/mL. Given the above results, this kind of compounds could serve as new lead compounds in the research of antimicrobial chemotherapy.

  20. Antibacterial/Antiviral Property and Mechanism of Dual-Functional Quaternized Pyridinium-type Copolymer

    Directory of Open Access Journals (Sweden)

    Yan Xue

    2015-11-01

    Full Text Available Due to the massive outbreaks of pathogen-caused diseases and the increase of drug-resistant pathogens, there is a particular interest in the development of novel disinfection agents with broad-spectrum antipathogenic activity. In the present study, water-soluble pyridinium-type polyvinylpyrrolidones with different counter anions were prepared. Structural characterization was conducted via 13C–1H heteronuclear single quantum coherence spectroscopy, static light scattering, UV spectrometry and apparent charge density. The influence of counter anion and polymer compositions on the antibacterial activity was studied against Staphylococcus aureus and Escherichia coli. Atomic force microscopy (AFM was applied for tracking the morphological alterations in bacterial cells induced by prepared polycations. It was found that the exposure of bacteria to the polycations resulted in the destruction of cell membranes and the leakage of cytoplasm. The antiviral activity of pyridinium-type polycations against enveloped influenza virus was evaluated via a plaque assay. The action mode against enveloped virus was depicted to rationalize the antiviral mechanism.

  1. (E)-1-Methyl-4-[2-(2-naphth-yl)vin-yl]pyridinium iodide.

    Science.gov (United States)

    Fun, Hoong-Kun; Chanawanno, Kullapa; Chantrapromma, Suchada

    2009-05-29

    In the title compound, C(18)H(16)N(+)·I(-), the cation is disordered over two orientations related by a 180° rotation about its long axis with occupancies of 0.554 (7) and 0.446 (7). Both disorder components exist in an E configuration. The dihedral angle between the pyridinium ring and the naphthalene ring system is 4.7 (6)° in the major disorder component and 1.6 (8)° in the minor component. In the crystal structure, centrosymmetrically related cations are stacked along the a axis, with significant π-π inter-actions between the pyridinium ring and the naphthalene ring system [centroid-centroid distance = 3.442 (9) Å]. The iodide ions are located between adjacent columns of cations. The cations are linked to the iodide ions by C-H⋯I inter-actions. Weak C-H⋯π inter-actions involving the methyl group are also observed.

  2. 2-Amino-6-methyl-pyridinium 2,2,2-tri-chloro-acetate.

    Science.gov (United States)

    Babu, K Syed Suresh; Peramaiyan, G; NizamMohideen, M; Mohan, R

    2014-04-01

    In the asymmetric unit of the title mol-ecular salt, C6H9N2 (+)·C2Cl3O2 (-), there are two independent 2-amino-6-methyl-pyridinium cations and two independent tri-chloro-acetate anions. The pyridine N atom of the 2-amino-6-methyl-pyridine mol-ecule is protonated and the geometries of these cations reveal amine-imine tautomerism. Both protonated 2-amino-6-methyl-pyridinium cations are essentially planar [maximum deviations = 0.026 (2) and 0.012 (2) Å]. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R 2 (2)(8) ring motif. These motifs are connected via N-H⋯O and C-H⋯O hydrogen bonds to form slabs parallel to (101).

  3. Towards the development of a direct electrochemical biodetector of avidin based on the poly(chloro amino β-styryl terthiophene)-coated glassy carbon electrode

    KAUST Repository

    Mehenni, Hakim

    2012-03-30

    In this study, a simple and direct biodetector was proposed, which was based on biotin immobilized onto a conducting polymer-coated electrode, for the detection of avidin, a highly stable glycoprotein found in egg-whites. Biotin was immobilized onto the electrode by covalent coupling to the primary amine group on the poly 3′-(3-chloro-4-amino-β-styryl)-(2,2′: 5′,2″-terthiophene) (PCAST), and the biotinavidin interaction was monitored by cyclic voltammetry. Incubation of the PCAST/biotin-modified-coated electrode with avidin in a phosphate buffered saline solution caused a significant change to its cyclic voltammogram, which was explained by the binding of avidin by biotin, and resulted in restricted ion transfer to and from the conducting polymer. This change was then utilized to detect avidin at 4 × 10 -6molL -1. © 2012 CSIRO.

  4. Polymorphism of pyridinium amphiphiles for gene delivery : Influence of ionic strength, helper lipid content, and plasmid DNA complexation

    NARCIS (Netherlands)

    Scarzello, Marco; Chupin, Vladimir; Wagenaar, Anno; Stuart, Marc C. A.; Engberts, Jan B. F. N.; Hulst, Ron

    Two double-tailed pyridinium cationic amphiphiles, differing only in the degree of unsaturation of the alkyl chains, have been selected for a detailed study of their aggregation behavior, under conditions employed for transfection experiments. The transfection efficiencies of the two molecules are

  5. The human immunodeficiency virus-reverse transcriptase inhibition activity of novel pyridine/pyridinium-type fullerene derivatives.

    Science.gov (United States)

    Yasuno, Takumi; Ohe, Tomoyuki; Takahashi, Kyoko; Nakamura, Shigeo; Mashino, Tadahiko

    2015-08-15

    In the present study, we describe the synthesis of a novel set of pyridine/pyridinium-type fullerene derivatives. The products were assessed for human immunodeficiency virus-reverse transcriptase inhibition activities. All novel fullerene derivatives showed potent human immunodeficiency virus-reverse transcriptase inhibition without cytotoxicity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Toxicology and carcinogenesis studies of methyl trans-styryl ketone (CAS NO 1896-62-4) in F344/N rats and B6C3F1 mice (feed and dermal studies).

    Science.gov (United States)

    2012-05-01

    Methyl trans-styryl ketone is used as a synthetic flavoring agent and a fragrance additive in food and personal care products. Methyl trans-styryl ketone was nominated for study by the National Cancer Institute due to widespread human exposure as a flavoring and fragrance additive, positive results in the Ames/Salmonella assay and the mouse lymphoma L5178Y/tk+/- assay, and as a representative of the α,β-unsaturated ketone chemical class. Male and female F344/N rats and B6C3F1 mice received methyl trans-styryl ketone (98.6% pure) in feed for 3 months and dermally for 3 months or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Escherichia coli, and mouse peripheral blood erythrocytes. Two-year studies were conducted to provide data for assessment of possible toxicity due to exposure to methyl trans-styryl ketone. The dermal route was chosen since this is the route for highest human exposure and due to studies demonstrating systemic exposure following dermal application to methyl trans-styryl ketone. 3-MONTH FEED STUDY IN RATS Groups of 10 male and 10 female rats were fed diets containing 0%, 0.025%, 0.05%, 0.1%, 0.2%, or 0.4% methyl trans-styryl ketone (equivalent to average daily doses of approximately 18, 36, 72, 145, or 290 mg methyl trans-styryl ketone/kg body weight to males and 19, 38, 77, 150, or 300 mg/kg to females) for 14 weeks. Groups of 10 male and 10 female clinical pathology rats were fed the same concentrations for 24 days. All core study rats survived to the end of the study. Final mean body weights of males and females receiving 0.4% and mean body weight gains of males receiving 0.4% were significantly less than those of the controls. Feed consumption by exposed groups was similar to that by the controls. Clinical findings included diarrhea and hyperactivity in males and females. Results of sperm motility and vaginal cytology evaluations indicated methyl trans-styryl ketone is unlikely to be a reproductive toxicant in

  7. Dyeing of hydrophobic fabrics with disperse dyes

    Directory of Open Access Journals (Sweden)

    VITHAL SOMA PATEL

    2001-06-01

    Full Text Available A series of disperse dyes has been synthesized by diazotisation of 2,6-dibromo-4-nitroaniline and coupled with various N-arylmaleimides. The dyes were characterized by IR spectral studies, visible absorption spectroscopy and elemental analysis. All the dyes were applied as disperse dyes on nylon, cellulose triacetate and polyester fabrics. These dyeswere found to give yellowish orange to deep brown shades with very good depth, levelness and brightness on different fabrics. The percentage dye bath exhaustion and fixation on fabrics were found to be very good. The light, washing, rubbing, perspiration and sublimation fastness properties of the dyed fabrics were found to be good to excellent.

  8. Crystal structure of 3-amino-pyridinium 1'-carb-oxy-ferrocene-1-carboxyl-ate.

    Science.gov (United States)

    Medved'ko, Aleksei V; Churakov, Andrei V; Yu, Haojie; Li, Wang; Vatsadze, Sergey Z

    2017-06-01

    The structure of the title salt, (C5H7N2)[Fe(C6H4O2)(C6H5O2)], consists of 3-amino-pyridinium cations and 1'-carb-oxy-ferrocene-1-carboxyl-ate monoanions. The ferrocenyl moiety of the anion adopts a typical sandwich structure, with Fe-C distances in the range 2.0270 (15)-2.0568 (17) Å. The anion possesses an eclipsed conformation, with the torsion angle φ (Csubst-Cpcent-Cpcent- Csubst) equal to 66.0°. The conformations of other 1'-carb-oxy-ferrocene-1-carboxyl-ate monoanions are compared and analyzed on the basis of literature data.

  9. 4-tert-Butyl-pyridinium triiodide-4-tert-butyl-pyridine (1/1).

    Science.gov (United States)

    He, Hongshan; Sykes, Andrew G

    2011-01-22

    The title compound, C(9)H(14)N(+)·I(3) (-)·C(9)H(13)N, consists of monoprotonated 4-tert-butyl-pyridinium cations and triiodide anions. The triiodide ion has near-symmetric linear geometry, with bond lengths of 2.9105 (4) Å (I-I) and a bond angle of 177.55 (3)° (I-I-I). For this room-temperature structure, the butyl group on the pyridine ring is disordered and has been treated as a rigid rotator, modeled in three separate positions with 1/3, 1/3, 1/3 occupancies. The cations assemble into dimeric forms by way of N-H⋯N hydrogen bonds.

  10. 4-tert-Butyl­pyridinium triiodide–4-tert-butyl­pyridine (1/1)

    Science.gov (United States)

    He, Hongshan; Sykes, Andrew G.

    2011-01-01

    The title compound, C9H14N+·I3 −·C9H13N, consists of monoprotonated 4-tert-butyl­pyridinium cations and triiodide anions. The triiodide ion has near-symmetric linear geometry, with bond lengths of 2.9105 (4) Å (I—I) and a bond angle of 177.55 (3)° (I—I—I). For this room-temperature structure, the butyl group on the pyridine ring is disordered and has been treated as a rigid rotator, modeled in three separate positions with 1/3, 1/3, 1/3 occupancies. The cations assemble into dimeric forms by way of N—H⋯N hydrogen bonds. PMID:21523100

  11. Oxidative desulfurization of fuel oil by pyridinium-based ionic liquids.

    Science.gov (United States)

    Zhao, Dishun; Wang, Yanan; Duan, Erhong

    2009-10-28

    In this work, an N-butyl-pyridinium-based ionic liquid [BPy]BF(4) was prepared. The effect of extraction desulfurization on model oil with thiophene and dibenzothiophene (DBT) was investigated. Ionic liquids and hydrogen peroxide (30%) were tested in extraction-oxidation desulfurization of model oil. The results show that the ionic liquid [BPy]BF(4) has a better desulfurization effect. The best technological conditions are: V(IL)/V(Oil) /V(H(2)O(2)) = 1:1:0.4, temperature 55 degrees C, the time 30 min. The ratio of desulfurization to thiophene and DBT reached 78.5% and 84.3% respectively, which is much higher than extraction desulfurization with simple ionic liquids. Under these conditions, the effect of desulfurization on gasoline was also investigated. The used ionic liquids can be recycled up to four times after regeneration.

  12. Structure-activity correlation in transfection promoted by pyridinium cationic lipids.

    Science.gov (United States)

    Parvizi-Bahktar, P; Mendez-Campos, J; Raju, L; Khalique, N A; Jubeli, E; Larsen, H; Nicholson, D; Pungente, M D; Fyles, T M

    2016-03-21

    The efficiency of the transfection of a plasmid DNA encoding a galactosidase promoted by a series of pyridinium lipids in mixtures with other cationic lipids and neutral lipids was assessed in CHO-K1 cells. We identify key molecular parameters of the lipids in the mixture - clog P, lipid length, partial molar volume - to predict the morphology of the lipid-DNA lipoplex and then correlate these same parameters with transfection efficiency in an in vitro assay. We define a Transfection Index that provides a linear correlation with normalized transfection efficiency over a series of 90 different lipoplex compositions. We also explore the influence of the same set of molecular parameters on the cytotoxicity of the formulations.

  13. High-pressure-induced phase transitions in the ferroelectric bis-thiourea pyridinium iodide inclusion compound

    Energy Technology Data Exchange (ETDEWEB)

    Bilski, P; Bobrowicz-Sarga, L; Czarnecki, P; Maluszynska, H; Wasicki, J [Institute of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland); Natkaniec, I [Frank Laboratory of Neutrons Physics, JINR, 141980 Dubna (Russian Federation)

    2008-12-03

    The effect of temperature and pressure on physical properties of the ferroelectric bis-thiourea pyridinium iodide inclusion compound has been studied by dielectric spectroscopy, neutron spectroscopy, neutron powder diffractometry, single crystal x-ray diffraction and nuclear magnetic resonance (NMR). At ambient pressure two structural phase transitions have been revealed: at T{sub 1} = 161 K between phases I and II and at T{sub 2} = 141 K between phases II and III. Phase III with increasing pressure splits into two phases, IIIa and IIIb. The temperatures of the phase transitions T{sub I-II}, T{sub II-IIIa} and T{sub IIIa-IIIb} increase with increasing pressure. The p-T phase diagram constructed for this compound shows two triple points of coordinates 150 K, 100 MPa and 115 K, 100 MPa.

  14. A theoretical and experimental exploration of the mechanism of microwave assisted 1,3-dipolar cycloaddition of pyridinium ylides to single walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Bayazit, Mustafa K., E-mail: m.bayazit@imperial.ac.uk [Department of Chemistry, University of Durham, Durham DH1 3LE (United Kingdom); Celebi, Nihat [Department of Chemistry, Abant Izzet Baysal University, Bolu 14280 (Turkey); Coleman, Karl S. [Department of Chemistry, University of Durham, Durham DH1 3LE (United Kingdom)

    2014-05-01

    Cycloaddition reactions have widely been used for surface functionalization of single walled carbon nanotubes (SWNTs). Here, 1,3-dipolar cycloaddition (1,3-DC) of two new pyridinium ylides, generated in-situ via the addition of triethylamine (NEt{sub 3}) to the Kröhnke salts N-(4-methyl sodium benzene sulfonate)-pyridinium bromide and N-(4-nitrobenzyl)-pyridinium bromide, to SWNTs under microwave conditions are assessed both theoretically using PM3 (RHF) type calculations and experimentally. Evidence of covalent surface modification is provided by FTIR, UV–vis–NIR and resonance Raman spectroscopy. Solubility of the modified SWNTs increases when compared to as-received SWNTs. Quantification of surface groups is performed via TGA-MS and XPS. 1,3-DC of pyridinium ylides with smaller HOMO–LUMO energy gap is found to be more selective to large diameter SWNTs. Theoretically predicted smaller energy gaps between HOMO{sub ylides} and LUMO{sub (8,8)} SWNT suggest that the charges are probably transferred from pyridinium ylides to SWNTs indicating HOMO{sub ylide}–LUMO{sub (8,8)} {sub SWNT} controlled 1,3-DC. Regioselectivity of second ylide addition as addendum to ylide–SWNT adduct is also discussed. - Graphical abstract: Display Omitted - Highlights: • PM3 (RHF) type calculations suggest that charges are probably transferred from HOMO of pyridinium ylides to LUMO of SWNTs. • Theoretical predictions indicate a HOMO{sub ylide}–LUMO{sub (8,8)} {sub SWNT} controlled 1,3-DC reaction (Type I). • Pyridinium ylides with smaller HOMO–LUMO energy gap is experimentally found to be more selective to large diameter SWNTs. • Reactivity of pyridinium ylide might be manipulated using strong electron withdrawing groups. • Graphene surface modification may be anticipated using the same approach.

  15. Tunable Microfluidic Dye Laser

    DEFF Research Database (Denmark)

    Olsen, Brian Bilenberg; Helbo, Bjarne; Kutter, Jörg Peter

    2003-01-01

    We present a tunable microfluidic dye laser fabricated in SU-8. The tunability is enabled by integrating a microfluidic diffusion mixer with an existing microfluidic dye laser design by Helbo et al. By controlling the relative flows in the mixer between a dye solution and a solvent......, the concentration of dye in the laser cavity can be adjusted, allowing the wavelength to be tuned. Wavelength tuning controlled by the dye concentration was demonstrated with macroscopic dye lasers already in 1971, but this principle only becomes practically applicable by the use of microfluidic mixing...

  16. Spectral Properties and Orientation of Voltage-Sensitive Dyes in Lipid Membranes

    KAUST Repository

    Matson, Maria

    2012-07-24

    Voltage-sensitive dyes are frequently used for probing variations in the electric potential across cell membranes. The dyes respond by changing their spectral properties: measured as shifts of wavelength of absorption or emission maxima or as changes of absorption or fluorescence intensity. Although such probes have been studied and used for decades, the mechanism behind their voltage sensitivity is still obscure. We ask whether the voltage response is due to electrochromism as a result of direct field interaction on the chromophore or to solvatochromism, which is the focus of this study, as result of changed environment or molecular alignment in the membrane. The spectral properties of three styryl dyes, di-4-ANEPPS, di-8-ANEPPS, and RH421, were investigated in solvents of varying polarity and in model membranes using spectroscopy. Using quantum mechanical calculations, the spectral dependence of monomer and dimer ANEPPS on solvent properties was modeled. Also, the kinetics of binding to lipid membranes and the binding geometry of the probe molecules were found relevant to address. The spectral properties of all three probes were found to be highly sensitive to the local environment, and the probes are oriented nearly parallel with the membrane normal. Slow binding kinetics and scattering in absorption spectra indicate, especially for di-8-ANEPPS, involvement of aggregation. On the basis of the experimental spectra and time-dependent density functional theory calculations, we find that aggregate formation may contribute to the blue-shifts seen for the dyes in decanol and when bound to membrane models. In conclusion, solvatochromic and other intermolecular interactions effects also need to be included when considering electrochromic response voltage-sensitive dyes. © 2012 American Chemical Society.

  17. Synthesis and crystal structure of a new pyridinium bromide salt: 4-methyl-1-(3-phenoxypropylpyridinium bromide

    Directory of Open Access Journals (Sweden)

    Musa A. Said

    2017-12-01

    Full Text Available In the cation of the title molecular salt, C15H18NO+·Br−, the pyridinium and phenyl rings are inclined to one another by 11.80 (8°. In the crystal, the Br− anion is linked to the cation by a C—H...Br hydrogen bond. The cations stack along the b-axis direction and are linked by further C—H...Br interactions, and offset π–π interactions [intercentroid distances = 3.5733 (19 and 3.8457 (19 Å], forming slabs parallel to the ab plane. The effects of the C—H...X− interaction on the NMR signals of the ortho- and meta-pyridinium protons in a series of related ionic liquids, viz. 4-methyl-1-(4-phenoxybutylpyridin-1-ium salts, are reported and discussed.

  18. Synthesis, spectroscopic and molecular docking studies of imidazolium and pyridinium based ionic liquids with HSA as potential antimicrobial agents

    Science.gov (United States)

    Trush, Maria M.; Semenyuta, Ivan V.; Vdovenko, Sergey I.; Rogalsky, Sergiy P.; Lobko, Evgeniya O.; Metelytsia, Larisa O.

    2017-06-01

    The interaction between human serum albumin (HSA) and synthesized imidazolium and pyridinium based ionic liquids (ILs), as good potential microbial growth inhibitors, was investigated by spectroscopic techniques combined with molecular docking analysis. All compounds were significant active against the tested bacterial and fungal strains. FT-IR spectroscopy indicated that the interaction of HSA with ILs generates considerable changes in protein secondary structure. The results of the molecular docking study showed that the studied ILs are able to firmly bind in the subdomain IIA of HSA with almost equal binding affinity (about -6.23 kcal/mol). Investigated HSA-ILs complex binds through hydrogen bonding or/and cation-π interactions. This study provides a better understanding of the binding of imidazolium and pyridinium based ILs to HSA and opens the way for their further biological and pharmaceutical investigations as candidates with antimicrobial properties.

  19. Benzidine Dyes Action Plan

    Science.gov (United States)

    This Action Plan addresses the use of benzidine-based dyes and benzidine congener-based dyes, both metalized and non-metalized, in products that would result in consumer exposure, such as for use to color textiles.

  20. 2-Oxo-2,3-dihydro-1H-imidazo[1,2-a]pyridinium iodide

    Directory of Open Access Journals (Sweden)

    Yong Nie

    2010-03-01

    Full Text Available In the title compound, C7H7N2O+·I−, the carbonyl C and O atoms of the cation and the iodide ion are situated on mirror planes. The mean plane of the imidazo[1,2-d]pyridinium cation is perpendicular to the mirror plane as a consequence of the disorder of the cation over two opposite orientations of equal occupancy. In the crystal, N—H...I interactions are present.

  1. Kinetics and Mechanism of the Oxidation of Lactic Acid and Mandelic Acid by Pyridinium Chlorochromate in Aqueous Acidic Medium

    Directory of Open Access Journals (Sweden)

    Sapana Jain

    2009-01-01

    Full Text Available Pyridinium chlorochromate (PCC act as two electron oxidant in kinetic studies of the oxidation of lactic and mandelic acid in acidic medium. The influence of several factors such as acidity, salts, solvent composition and temperature on the reaction rate has been studied. The reaction shows first order dependence with respect to [PCC] and [H+]. The various thermodynamic parameters have been evaluated. Products as oxoacids and absence of free radical were confirmed. Suitable reaction mechanism has been proposed.

  2. Chemistry of Natural Dyes

    Indian Academy of Sciences (India)

    animals have been identified as potentially rich in natural dye contents, and some of them have been used for natural dyeing for quite some time. Various parts of plants like roots, stems, barks, leaves, fruits and seeds may contain colouring matter which can be exploited. Normally natural dyes are extracted from the roots ...

  3. Extraction of dye

    African Journals Online (AJOL)

    The study investigated the effects of different methods of application of selected mordants on dyeing woven cotton with natural dyes from the leaves of ... INTRODUCTION. In Uganda, plants have traditionally been utilized as a source of colorants for dyeing mats, ropes and other home based materials for a long time.

  4. Development of an avidin sensor based on the poly(methoxy amino-β-styryl terthiophene)-coated glassy carbon electrode

    KAUST Repository

    Mehenni, Hakim

    2012-03-01

    In this study, a simple and direct biosensor was proposed, which was based on biotin immobilized onto a conducting polymer-coated electrode, for the determination of avidin, a highly stable glycoprotein found in egg whites. Biotin was immobilized onto the electrode by covalent coupling to the primary amine group on poly-3′-(2-methoxy-5-amino-β-styryl)-(2,2′: 5′,2″-terthiophene) (PMAST), and the biotin-avidin interaction was monitored by square-wave voltammetry. Incubation of the PMAST/biotin-modified coated electrode with avidin in a phosphate-buffered saline solution caused a significant change to its square-wave voltammogram, which was explained by the binding of avidin by biotin, and resulted in restricted ion transfer to and from the conducting polymer. This change was then utilized to determine avidin. Importantly, we found a linear relationship for the avidin sensor in the range of 4 × 10 -14 to 3 × 10 -4 mol/L, and the detection limit was determined to be approximately 10 -14 mol/L. © 2012 Published by NRC Research Press.

  5. Investigation of thermodynamic properties of poly(methyl methacrylate-co-n-butylacrylate-co-cyclopentyl styryl-polyhedral oligomeric silsesquioxane) by inverse gas chromatography.

    Science.gov (United States)

    Zou, Qi-Chao; Zhang, Shi-Ling; Wang, Shi-Min; Wu, Li-Min

    2006-10-06

    The thermodynamic properties of poly(methyl methacrylate-co-butyl acrylate-co-cyclo -pentylstyryl polyhedral oligomeric silsesquioxane) (poly(MMA-co-BA-co-styryl-POSS)) were investigated by means of inverse gas chromatography (IGC) using 20 different kinds of solvents as the probes. Some thermodynamic parameters, such as molar heats of sorption, weight fraction activity coefficient, Flory-Huggins interaction parameter, partial molar heats of mixing and solubility parameter were obtained to judge the interactions between POSS-contained polymers and solvents and the solubility of the polymers in these solvents. It was found that acetates, aromatic hydrocarbons and hydrocarbon halides were good solvents, n-hexane, ethanol, n-propanol, n-butanol and n-pentanol were moderate solvents, while n-heptane, n-octane, n-nonane, n-decane and methanol were poor solvents for all POSS-contained polymers within the experimental temperature range. Incorporation of POSS in polymer increased the solubility of polymers in solvents, and the more the POSS in polymer was, the better the solubility was and stronger the hydrogen bonding interaction was, but the POSS content in polymers seemed to have no obvious influence on the solubility parameter of polymers.

  6. C-2 (E)-4-(Styryl)aniline substituted diphenylpyrimidine derivatives (Sty-DPPYs) as specific kinase inhibitors targeting clinical resistance related EGFR(T790M) mutant.

    Science.gov (United States)

    Song, Anran; Zhang, Jianbin; Ge, Yang; Wang, Changyuan; Meng, Qiang; Tang, Zeyao; Peng, Jinyong; Liu, Kexin; Li, Yanxia; Ma, Xiaodong

    2017-05-15

    With the aim to overcome the drug resistance induced by the EGFR T790M mutation (EGFR(T790M)), herein, a family of diphenylpyrimidine derivatives (Sty-DPPYs) bearing a C-2 (E)-4-(styryl)aniline functionality were designed and synthesized as potential EGFR(T790M) inhibitors. Among them, the compound 10e displayed strong potency against the EGFR(T790M) enzyme, with the IC50 of 11.0nM. Compound 10e also showed a higher SI value (SI=49.0) than rociletinib (SI=21.4), indicating its less side effect. In addition, compound 10e could effectively inhibit the proliferation of H1975 cells harboring the EGFR(T790M) mutation, within the concentration of 2.91μM. Significantly, compound 10e has low toxicity against the normal HBE cell (IC50=22.48μM). This work provided new insights into the discovery of potent and selective inhibitor against EGFR(T790M) over wild-type (EGFR(WT)). Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Toxicology of food dyes.

    Science.gov (United States)

    Kobylewski, Sarah; Jacobson, Michael F

    2012-01-01

    Food dyes, synthesized originally from coal tar and now petroleum, have long been controversial because of safety concerns. Many dyes have been banned because of their adverse effects on laboratory animals or inadequate testing. This review finds that all of the nine currently US-approved dyes raise health concerns of varying degrees. Red 3 causes cancer in animals, and there is evidence that several other dyes also are carcinogenic. Three dyes (Red 40, Yellow 5, and Yellow 6) have been found to be contaminated with benzidine or other carcinogens. At least four dyes (Blue 1, Red 40, Yellow 5, and Yellow 6) cause hypersensitivity reactions. Numerous microbiological and rodent studies of Yellow 5 were positive for genotoxicity. Toxicity tests on two dyes (Citrus Red 2 and Orange B) also suggest safety concerns, but Citrus Red 2 is used at low levels and only on some Florida oranges and Orange B has not been used for several years. The inadequacy of much of the testing and the evidence for carcinogenicity, genotoxicity, and hypersensitivity, coupled with the fact that dyes do not improve the safety or nutritional quality of foods, indicates that all of the currently used dyes should be removed from the food supply and replaced, if at all, by safer colorings. It is recommended that regulatory authorities require better and independent toxicity testing, exercise greater caution regarding continued approval of these dyes, and in the future approve only well-tested, safe dyes.

  8. Hair dye contact allergy

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rastogi, Suresh Chandra; Andersen, Klaus Ejner

    2004-01-01

    Colouring of hair can cause severe allergic contact dermatitis. The most frequently reported hair dye allergens are p-phenylenediamine (PPD) and toluene-2,5-diamine, which are included in, respectively, the patch test standard series and the hairdressers series. The aim of the present study...... was to identify dye precursors and couplers in hair dyeing products causing clinical hair dye dermatitis and to compare the data with the contents of these compounds in a randomly selected set of similar products. The patient material comprised 9 cases of characteristic clinical allergic hair dye reaction, where...... exposure history and patch testing had identified a specific hair dye product as the cause of the reaction. The 9 products used by the patients were subjected to chemical analysis. 8 hair dye products contained toluene-2,5-diamine (0.18 to 0.98%). PPD (0.27%) was found in 1 product, and m-aminophenol (0...

  9. Synthesis and thermodynamic properties of a novel pyridinium-based asymmetrical gemini ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xuzhao; Wang, Jun; Zou, Wenyuan; Wu, Jinchao [Zhengzhou University of Light Industry, Zhengzhou (China)

    2015-12-15

    A novel asymmetrical gemini ionic liquid (GIL), [1-(1-pyridinium-yl-hexyl)-6-methylpiperidinium] dihexafluorophosphate ([PyC{sub 6}MPi][PF{sub 6}]{sub 2}) combined with pyridine, 1-methylpiperidine by 1,6-dibromohexane with PF{sub 6} as anion, was synthesized and characterized by 1H NMR and IR. The molar heat capacity of the GIL was measured via differential scanning calorimetry from 298.15 K to 448.15 K under atmospheric pressure. No phase transition or other thermal anomaly was observed in the solid-phase region (298.15 K to 358.15 K) and liquid-phase region (403.15 K to 448.15 K). The basic properties and thermodynamic functions of the GIL, such as melting point, molar enthalpy and entropy of fusion, heat capacity, enthalpy HT-H298.15 K, and entropy S{sub T}-S{sub 298.15} K, were also determined from the experimental data. Thermal decomposition kinetics of [PyC{sub 6}MPi][PF{sub 6}]{sub 2} were investigated by using non-isothermal thermogravimetric analysis in pure nitrogen atmosphere at various heating rates. Thermal decomposition data were, respectively, correlated with Friedman method, Ozawa-Flynn-Wall equation, and ASTM model. The activation energy (E) and pre-exponential factor (logA) values were obtained by using the above three methods.

  10. Pyridinium ionic liquid-based liquid-solid extraction of inorganic and organic iodine from Laminaria.

    Science.gov (United States)

    Peng, Li-Qing; Yu, Wen-Yan; Xu, Jing-Jing; Cao, Jun

    2018-01-15

    A simple, green and effective extraction method, namely, pyridinium ionic liquid- (IL) based liquid-solid extraction (LSE), was first designed to extract the main inorganic and organic iodine compounds (I-, monoiodo-tyrosine (MIT) and diiodo-tyrosine (DIT)). The optimal extraction conditions were as follows: ultrasonic intensity 100W, IL ([EPy]Br) concentration 200mM, extraction time 30min, liquid/solid ratio 10mL/g, and pH value 6.5. The morphologies of Laminaria were studied by scanning electron microscopy and transmission electron microscopy. The recovery values of I-, MIT and DIT from Laminaria were in the range of 88% to 94%, and limits of detection were in the range of 59.40 to 283.6ng/g. The proposed method was applied to the extraction and determination of iodine compounds in three Laminaria. The results showed that IL-based LSE could be a promising method for rapid extraction of bioactive iodine from complex food matrices. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Sodium carbonate as phase promoter in aqueous solutions of imidazolium and pyridinium ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Deive, Francisco J. [Chemical Engineering Department, University of Santiago de Compostela, E-15782 Santiago de Compostela (Spain); Rivas, Miguel A. [Applied Physics Department, University of Vigo, 36310 Vigo (Spain); Rodriguez, Ana, E-mail: aroguez@uvigo.es [Chemical Engineering Department, University of Vigo, 36310 Vigo (Spain)

    2011-08-15

    Highlights: > The discovery of novel aqueous two-phase systems, exclusively formed by the mixture of an ionic liquid and sodium carbonate is presented. > We explore for the first time the ability of pyridinium-based ionic liquids to form aqueous biphasic systems. > A first advance of the benefits of using benzylimidazolium-based ionic liquids for aqueous two-phase systems is proposed. - Abstract: Several methylsulfate and chloride anion-based ionic liquids, such as 1-alkyl-3-methyl imidazolium methyl sulfate, C{sub n}MIM CH{sub 3}SO{sub 4} (n = 1, 2, and 4), 1-benzyl-3-methyl imidazolium methyl sulfate, BzMIM CH{sub 3}SO{sub 4}, 1-benzyl, or hexyl-3-methyl imidazolium chloride, XMIM Cl (X = Bz and Hx), and methylpyridinium methylsulfate, Mpy CH{sub 3}SO{sub 4}, with sodium carbonate, Na{sub 2}CO{sub 3}, as phase forming salt, have been investigated and discussed for their potential use in separations based on aqueous two-phase systems (ATPS). Phase diagrams have been experimentally ascertained at T = 298.15 K, and Merchuck equation and a variation of this model have been used for correlating the binodal data. The alkyl chain length in the cation and the type of anion and cation have been explored and discussed due to their decisive influence in the ATPS behavior. The consistence of tie-line data was ascertained by applying the Othmer-Tobias and Bancroft equations.

  12. Oxidation desulfurization of fuel using pyridinium-based ionic liquids as phase-transfer catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Dishun; Wang, Yanan; Duan, Erhong; Zhang, Juan

    2010-12-15

    In this work, several ionic liquids based on pyridinium cations are prepared. The ionic liquids are employed as phase-transfer catalysts (PTCs) for phase-transfer catalytic oxidation of dibenzothiophene (DBT) dissolved in n-octane. The partition coefficients of DBT between ionic liquids and n-octane are investigated. Then H{sub 2}O{sub 2}-formic acid is used as an oxidant and ionic liquids are used as PTCs. The reaction turns to be heterogeneous and desulfurization rate of DBT increased apparently. When IL ([BPy]HSO{sub 4}) is used as PTC, and the condition are: temperature is 60 C, time is 60 min, H{sub 2}O{sub 2}/sulfur molar ratio (O/S) is 4, the desulfurization rate reaches the maximum (93.3%), and the desulfurization of the real gasoline is also investigated, 87.7% of sulfur contents are removed under optima reaction conditions. The PTC [BPy]HSO{sub 4} can be recycled for five times without significant decrease in activity. (author)

  13. 2,3-Diamino-pyridinium sorbate-sorbic acid (1/1).

    Science.gov (United States)

    Hemamalini, Madhukar; Goh, Jia Hao; Fun, Hoong-Kun

    2012-01-01

    In the title mol-ecular salt-adduct, C(5)H(8)N(3) (+)·C(6)H(7)O(2) (-)·C(6)H(8)O(2), the 2,3-diamino-pyridinium cation is essentially planar, with a maximum deviation of 0.013 (2) Å, and is protanated at its pyridine N atom. The sorbate anion and sorbic acid mol-ecules exist in extended conformations. In the crystal, the protonated N atom and one of the two amino-group H atoms are hydrogen bonded to the sorbate anion through a pair of N-H⋯O hydrogen bonds, forming an R(1) (2)(6) ring motif. The carboxyl groups of the sorbic acid mol-ecules and the carboxyl-ate groups of the sorbate anions are connected via O-H⋯O hydrogen bonds. Furthermore, the ion pairs and neutral mol-ecules are connected via inter-molecular N-H⋯O hydrogen bonds, forming sheets lying parallel to (100).

  14. Efficient synthesis and evaluation of bis-pyridinium/bis-quinolinium metallosalophens as antibiotic and antitumor candidates

    Science.gov (United States)

    Elshaarawy, Reda F. M.; Eldeen, Ibrahim M.; Hassan, Eman M.

    2017-01-01

    Inspired with the pharmacological diversity of salophens and in our endeavor to explore a new strategy which may conflict the invasion of drug resistance, we report herein efficient synthetic routes for the synthesis of new RO-salophen(Cl), pyridinium/quinolinium-based salophens (3a-e) and metallosalophens (4a-j). These new architectures have been structurally characterized by elemental and spectral analysis as well pharmacologically evaluated for their in vitro antimicrobial, against a common panel of pathogenic bacterial and fungal strains, and anticancer activities against human colon carcinoma (HCT-116) cell lines. Antimicrobial assay results revealed that all tested compounds exhibited moderate to superb broad-spectrum efficacy in comparison to the standard antibiotic with a preferential ability to perform as a fungicides than to act as bactericides. Noteworthy, VO(II)-salophens are more effective in reduction HCT-116 cell viability than Cu(II)-salophens. For example, VO(II)-salophen3 (4f) (IC50 = 2.13 μg/mL) was ca. 10-fold more efficient than Cu(II)-salophen3 (4e) (IC50 = 20.30 μg/mL).

  15. Treatment of dyeing wastewater including reactive dyes (Reactive ...

    African Journals Online (AJOL)

    2013-08-15

    Aug 15, 2013 ... Treatment of dyeing wastewater including reactive dyes. (Reactive Red RB, Reactive Black B, ... Keywords: Rhizopus arrhizus, wastewater treatment, decolourisation, textile dye. INTRODUCTION. Dyeing effluents ... as bacteria, yeasts, algae and fungi, are able to remove differ- ent classes of dyes (Fu and ...

  16. Synthesis and Computational Studies Demonstrate the Utility of an Intramolecular Styryl Diels-Alder Reaction and Di-t-butylhydroxytoluene Assisted [1,3]-Shift to Construct Anticancer dl-Deoxypodophyllotoxin.

    Science.gov (United States)

    Saavedra, Diana I; Rencher, Benjamin D; Kwon, Doo-Hyun; Smith, Stacey J; Ess, Daniel H; Andrus, Merritt B

    2018-01-31

    Deoxypodophyllotoxin is a secondary metabolite lignan possessing potent anticancer activity with potential as a precursor for known anticancer drugs, but its use is limited by scarcity from natural sources. We here report the total synthesis of racemic deoxypodophyllotoxin in seven steps using an intramolecular styryl Diels-Alder reaction strategy uniquely suited to assemble the deoxypodophyllotoxin core. Density functional theory was used to analyze concerted, polar, and singlet-open-shell diradical reaction pathways, which identified a low-energy concerted [4 + 2] Diels-Alder pathway followed by a faster di-t-butylhydroxytoluene assisted [1,3]-formal hydrogen shift.

  17. WATERLESS DYEING [REVIEW

    Directory of Open Access Journals (Sweden)

    DEVRENT Nalan

    2015-05-01

    Full Text Available The textile industry is believed to be one of the biggest consumers of water. Water consumption and exhaustion in dyeing textile materials in conventional methods is an important environmental problem. The cost of waste water treatment will cause a prominent problem in the future as it does today. Increasing consideration of ecologic consequences of industrial processes as well as legislation enforcing the avoidance of environmental problems have caused a reorientation of thinking and promoted projects for replacement of conventional technologies. One of these new technologies is dyeing in supercritical fluids. Dyeing with supercritical carbon dioxide is a favourable concept considering the value of water as a natural resource and the cost of waste water treatment. This dyeing method offers many advantages over conventional aqueous dyeing: During this dyeing process no water is used, therefore there is no waste water problem, no other chemicals are required; the carbon dioxide can be recycled; the dystuff which is not adsorbed on the substrate can be collected and reused; The necessary energy consumption in this process is relatively lower than is needed to heat water in conventional methods of dyeing. Due to unnecessary of drying process, it helps to save both energy and time; and dyeing cycle is shorter compared with traditional methods. In addition carbon dioxide is non-toxic and non-flammable. Supercritical fluid, supercritical dyeing, disperse dyestuffs, solid-fluid equilibrium

  18. Formation of nitrogen-containing polycyclic cations by gas-phase and intracluster reactions of acetylene with the pyridinium and pyrimidinium ions.

    Science.gov (United States)

    Soliman, Abdel-Rahman; Hamid, Ahmed M; Attah, Isaac; Momoh, Paul; El-Shall, M Samy

    2013-01-09

    Here, we present evidence from laboratory experiments for the formation of nitrogen-containing complex organic ions by sequential reactions of acetylene with the pyridinium and pyrimidinium ions in the gas phase and within ionized pyridine-acetylene binary clusters. Additions of five and two acetylene molecules onto the pyridinium and pyrimidinium ions, respectively, at room temperature are observed. Second-order rate coefficients of the overall reaction of acetylene with the pyridinium and pyrimidinium ions are measured as 9.0 × 10(-11) and 1.4 × 10(-9) cm(3) s(-1), respectively, indicating reaction efficiencies of about 6% and 100%, respectively, at room temperature. At high temperatures, only two acetylene molecules are added to the pyridinium and pyrimidinium ions, suggesting covalent bond formation. A combination of ion dissociation and ion mobility experiments with DFT calculations reveals that the addition of acetylene into the pyridinium ion occurs through the N-atom of the pyridinium ion. The relatively high reaction efficiency is consistent with the absence of a barrier in the exothermic N-C bond forming reaction leading to the formation of the C(7)H(7)N(•+) covalent adduct. An exothermic addition/H-elimination reaction of acetylene with the C(7)H(7)N(•+) adduct is observed leading to the formation of a bicyclic quinolizinium cation (C(9)H(8)N(+)). Similar chemistry is observed in the sequential reactions of acetylene with the pyrimidinium ion. The second acetylene addition onto the pyrimidinium ion involves an exclusive addition/H-elimination reaction at room temperature leading to the formation of a bicyclic pyrimidinium cation (C(8)H(7)N(2)(+)). The high reactivity of the pyridinium and pyrimidinium ions toward acetylene is in sharp contrast to the very low reactivity of the benzene cation, which has a reaction efficiency of 10(-4)-10(-5). This indicates that the presence of a nitrogen atom within the aromatic ring enhances the ring growth

  19. CATALYTIC DETOXIFICATION OF NERVE AGENT AND PESTICIDE ORGANOPHOSPHATES BY BUTYRYLCHOLINESTERASE ASSISTED WITH NON-PYRIDINIUM OXIMES

    Science.gov (United States)

    Radić, Zoran; Dale, Trevor; Kovarik, Zrinka; Berend, Suzana; Garcia, Edzna; Zhang, Limin; Amitai, Gabriel; Green, Carol; Radić, Božica; Duggan, Brendan M.; Ajami, Dariush; Rebek, Julius; Taylor, Palmer

    2016-01-01

    SYNOPSIS We present here a comprehensive in vitro, ex vivo and in vivo study on hydrolytic detoxification of nerve agent and pesticide organophosphates (OPs) catalyzed by purified human butyrylcholinesterase (hBChE) in combination with novel non-pyridinium oxime reactivators. We identified 2-trimethylammonio-6-hydroxybenzaldehyde oxime (TAB2OH) as an efficient reactivator of OP-hBChE conjugates formed by the nerve agents, VX and cyclosarin, and the pesticide, paraoxon. It was also functional in reactivation of sarin and tabun inhibited hBChE. A three to five-fold enhancement of in vitro reactivation of VX, cyclosarin and paraoxon inhibited hBChE was observed, when compared to the commonly used N-methylpyridinium aldoxime reactivator, 2PAM. Kinetic analysis showed the enhancement resulted from improved molecular recognition of corresponding OP-hBChE conjugates by TAB2OH. The unique features of TAB2OH stem from an exocyclic quaternary nitrogen and a hydroxyl, both ortho to an oxime group on a benzene ring. pH dependences reveal participation of the hydroxyl (pKa=7.6) forming an additional ionizing nucleophile to potentiate the oxime (pKa=10) at physiological pH. The TAB2OH protective indices in therapy of sarin and paraoxon exposed mice were enhanced by 30% – 60% when they were treated with a combination of TAB2OH and sub-stoichiometric hBChE. These results establish that oxime-assisted catalysis is feasible for OP bioscavenging. PMID:23216060

  20. Influence of counterions on the interaction of pyridinium salts with model membranes.

    Science.gov (United States)

    Sarapuk, J; Kleszczyńska, H; Pernak, J; Kalewska, J; Rózycka-Roszak, B

    1999-11-01

    The interaction of pyridinium salts (PS) with red blood cells and planar lipid membranes was studied. The aim of the work was to find whether certain cationic surfactant counterion influence its possible biological activity. The counterions studied were Cl-, Br-, I-, ClO4-, BF4- and NO3-. The model membranes used were erythrocyte and planar lipid membranes (BLM). At high concentration the salts caused 100% erythrocyte hemolysis (C100) or broke BLMs (CC). Both parameters describe mechanical properties of model membranes. It was found that the efficiency of the surfactant to destabilize model membranes depended to some degree on its counterion. In both, erythrocyte and BLM experiments, the highest efficiency was observed for Br-, the lowest for NO3-. The influence of all other anions on surfactant efficiency changed between these two extremities; that of chloride and perchlorate ions was similar. Some differences were found in the case of BF4- ion. Its influence on hemolytic possibilities of PS was significant while BLM destruction required relatively high concentration of this anion. Apparently, the influence of various anions on the destructive action of PS on the model membrane used may be attributed to different mobilities and radii of hydrated ions and hence, to different possibilities of particular anions to modify the surface potential of model membranes. This can lead to a differentiated interaction of PS with modified bilayers. Moreover, the effect of anions on the water structure must be taken into account. It is important whether the anions can be classified as water ordering kosmotropes that hold the first hydration shell tightly or water disordering chaotropes that hold water molecules in that shell loosely.

  1. 2-Pyridinium propanol hydrogen squarate: experimental and computational study of a nonlinear optical material.

    Science.gov (United States)

    Korkmaz, Ufuk; Bulut, Ahmet

    2015-02-05

    The experimental and theoretical investigation of a novel organic nonlinear optical (NLO) squarate salt of 2-pyridinium propanol hydrogen squarate (1), C8H12ON(+)·C4HO4(-), were reported in this study. The crystal structure of the title compound was found to crystallize in the triclinic P-1 space group. In the asymmetric unit each squaric acid molecules have donated one H atom to the pyridines N1 and N2 atoms of a 2-pyridine propanol molecule, forming the salt (1). The X-ray analysis clearly indicated that the crystal packing has shown the hydrogen bonding ring pattern of D2(2)(10) (α-dimer) through N-H⋯O interactions. The structural and vibrational properties of the compound were also studied by computational methods of ab initio performed on the compound at DFT/B3LYP/6-31++G(d,p) (2) and HF/6-31++G(d,p) (3) level of theory. The calculation results on the basis of two models for both the optimized molecular structure and vibrational properties for the 1 are presented and compared with the X-ray analysis result. The molecular electrostatic potential (MEP), electronic absorption spectra, frontier molecular orbitals (FMOs), conformational flexibility and non-linear optical properties (NLO) of the title compound were also studied at the 2 level and the results are reported. In order to evaluate the suitability for NLO applications thermal analysis (TG, DTA and DTG) data of 1 were also obtained. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Oxazine laser dyes

    Science.gov (United States)

    Hammond, Peter R.; Field, George F.

    1992-01-01

    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##

  3. Anaerobic azo dye reduction

    NARCIS (Netherlands)

    Zee, van der F.P.

    2002-01-01

    Azo dyes, aromatic moieties linked together by azo (-N=N-) chromophores, represent the largest class of dyes used in textile-processing and other industries. The release of these compounds into the environment is undesirable, not only because of their colour, but also

  4. Analogues of platelet activating factor. 8. Antagonists of PAF containing an aromatic ring linked to a pyridinium ring.

    Science.gov (United States)

    Trova, M P; Wissner, A; Carroll, M L; Kerwar, S S; Pickett, W C; Schaub, R E; Torley, L W; Kohler, C A

    1993-03-05

    A series of platelet activating factor (PAF) antagonists containing a quaternary pyridinium ring connected through an amide, imide, or carbamate linkage to a substituted aromatic ring was prepared. Of these compounds, those containing a branched imide linkage of the form (CON-(COCH3)CH2, 37-51, and 59) generally showed excellent PAF antagonist properties in vitro. Structure-activity relationships within this series of compounds were studied extensively with respect to substituents and the position of substitution in both the aromatic and pyridinium rings. Several of these compounds (40 and 44) showed in vitro PAF antagonism at less than 0.1 microM and are as potent as CV-6209, the most potent PAF antagonist reported in the literature. Less active PAF antagonists were those bearing simple amide linkages (20-23, 27-29, and 31-35), linear imide linkages (62-63), or carbamate linkages (66 and 68), between the two aromatic rings. A number of our PAF antagonists were tested in vivo in mice and rabbits for their ability to protect these animals against a lethal injection of PAF. Those antagonists that are particularly potent (IC50 < 0.1 microM) provide excellent protection against an LD97 dose of PAF in rabbits. The relationships between structure and activity in vitro and in vivo are presented and compared to literature standards.

  5. Synthesis, characterization, DNA-Binding, enzyme inhibition and antioxidant studies of new N-methylated derivatives of pyridinium amine

    Science.gov (United States)

    Zafar, Muhammad Naveed; Perveen, Fouzia; Nazar, Muhammad Faizan; Mughal, Ehsan Ullah; Rafique, Humera; Tahir, Muhammad Nawaz; Akbar, Muhammad Sharif; Zahra, Sabeen

    2017-06-01

    A series of novel N-methylated derivatives of pyridinium amine, [L1][Tf]-[L5][Tf], were synthesized and characterized by FTIR, NMR, MS and XRD analyses. Preliminary biological screening of these compounds including antioxidant, enzyme inhibition and DNA (salmon sperm) interaction studies were also carried out. The targeted compounds were synthesized by a melt reaction between 4-chloro-N-methyl pyridinium triflate and corresponding amines (1-naphthyl amine, o-ansidine, 2-nitroaniline, p-ansidine and cyclohexyl amine) at temperature of 230 °C. The DPPH radical antioxidant scavenging activities of these compounds at maximum concentration of 50 μg/mL were observed in the range of 60-70%. Acetylcholine esterase (AChE) and Butylcholine esterase (BChE) inhibitory activities of synthesized compounds at 2 mM concentration were also measured to be at maximum of 79 and 71% respectively. The spectral behavior of ligand-DNA obtained from photo-luminescent measurements showed that all ligands bind with DNA via non-covalent interactions. The binding constant values were determined by UV-visible and fluorescence spectroscopy and were quite close to that obtained from molecular docking studies.

  6. (E)-1-Methyl-4-[2-(1-naphth-yl)vin-yl]pyridinium 4-chloro-benzene-sulfonate.

    Science.gov (United States)

    Chantrapromma, Suchada; Chanawanno, Kullapa; Fun, Hoong-Kun

    2009-11-18

    In the title compound, C(18)H(16)N(+)·C(6)H(4)ClO(3)S(-), the cation exists in an E configuration with respect to the central C=C bond. The naphthalene ring system is slightly bent, the dihedral angle between the two aromatic rings being 3.71 (14)°. The whole cation is twisted, the dihedral angles between the pyridinium and the two aromatic rings of the naphthalene ring system being 47.44 (14) and 50.81 (14)°. The pyridinium ring and the benzene ring of the anion are inclined to each other at a dihedral angle of 68.21 (13)°. In the crystal structure, the cations and anions are arranged alternately with the cations stacked in an anti-parallel manner along the c axis and the anions linked into chains along the same direction. The cations are linked to the anions by weak C-H⋯O inter-actions, forming a three-dimensional network. The crystal structure is further stabilized by C-H⋯π inter-actions and π-π contacts with centroid-centroid distances of 3.6374 (16) and 3.6733 (17) Å. A short Cl⋯O contact [3.108 (2) Å] is also present.

  7. Disiloxanes and Functionalized Silica Gels: One Route, Two Complementary Outcomes-Guanidinium and Pyridinium Ion-Exchangers.

    Directory of Open Access Journals (Sweden)

    Łukasz Tabisz

    Full Text Available Five novel disiloxane compounds comprising guanidinium and pyridinium moieties were obtained with high yields and purity. The verified synthetic pathways were then applied for modification of pre-functionalized silica gel, producing materials with the analogous organic side-chains. These halide-containing compounds and materials were then compared as to their ion-exchange properties: two disiloxanes proved to be effective in leaching different anions (nitrate, benzoate and ascorbate from solid to organic phase, and pyridinium-functionalized silica gels showed selectivity towards perchlorate ion, removing it from methanolic solutions with preference to other singly charged anions. The results presented demonstrate that both compounds and materials containing silicon-carbon bonds can be produced using the same methodology, but offer strikingly different application opportunities. Comparison of their properties provides additional insight into the binding mode of different anions and hints at how the transition from a flexible siloxane bridge to immobilization on solid surface influences anion-binding selectivity. Additionally, one of the siloxane dipodands was found to form a crystalline and poorly soluble nitrate salt (1.316 g/L, water, although it was miscible with a wide range of solvents as a hydrochloride. A possible explanation is given with the help of semi-empirical calculations. A simple, time- and cost-efficient automated potentiometric titration methodology was used as a viable analytical tool for studying ion-exchange processes for both compounds and materials, in addition to standard NMR, FT-IR and ESI-MS methods.

  8. Unsymmetrical Heptamethine Dyes for NIR Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Thomas Geiger

    2014-01-01

    Full Text Available Seven unsymmetrical heptamethine dyes with carboxylic acid functionality were synthesized and characterized. These near-infrared dyes exhibit outstanding photophysical properties depending on their heterocyclic moieties and molecular structure. As proof of principle, the dyes were used as photosensitizers in dye-sensitized solar cells. Using the most promising dye, an overall conversion efficiency of 1.22% and an almost colorless solar cell were achieved.

  9. Dyeing of Polyester with Disperse Dyes: Part 2. Synthesis and Dyeing Characteristics of Some Azo Disperse Dyes for Polyester Fabrics

    Directory of Open Access Journals (Sweden)

    Alya M. Al-Etaibi

    2016-06-01

    Full Text Available The goal of this study was to utilize carrier for accelerating the rate of dyeing not only to enhance dyeing of polyester fabrics dyed with disperse dyes 3a,b, but also to save energy. Both the color strength expressed as dye uptake and the fastness properties of the dyed fabrics were evaluated.

  10. Dyeing of Polyester with Disperse Dyes: Part 2. Synthesis and Dyeing Characteristics of Some Azo Disperse Dyes for Polyester Fabrics.

    Science.gov (United States)

    Al-Etaibi, Alya M; Alnassar, Huda S; El-Apasery, Morsy Ahmed

    2016-06-29

    The goal of this study was to utilize carrier for accelerating the rate of dyeing not only to enhance dyeing of polyester fabrics dyed with disperse dyes 3a,b, but also to save energy. Both the color strength expressed as dye uptake and the fastness properties of the dyed fabrics were evaluated.

  11. Bis(4-amino­pyridinium) hexa­aqua­nickel(II) bis­(sulfate)

    Science.gov (United States)

    Sahbani, Thameur; Smirani Sta, Wajda; Rzaigui, Mohamed

    2014-01-01

    In the title compound, (C5H7N2)2[Ni(H2O)6](SO4)2, the NiII cation is located on an inversion centre and is coordinated by six aqua ligands in a slightly distorted octa­hedral coordination environment. The [Ni(H2O)6]2+ ions are connected through an extensive network of O—H⋯O hydrogen bonds to sulfate anions, leading to the formation of layers parallel to (001). The 4-amino­pyridinium cations are located between these layers and are connected to the anionic framework by N—H⋯O hydrogen bonds. Weak π–π inter­actions between the pyridine rings, with a centroid–centroid distance of 3.754 (9) Å, provide additional stability to the crystal packing. PMID:24526957

  12. Polycationic antimicrobial dendrimers: a comparison of alkyl pyridinium,quaternary ammonium, quaternary phosphonium and tertiary sulfonium salts

    Science.gov (United States)

    Chen, Chris; Cooper, Stuart

    2000-03-01

    Polycationic biocides usually kill bacteria through the interactions of the positively charged head groups with negatively charged bacteria and the interactions of the hydrophobic segments with phospholipid cell membranes, which implies that high local charge densities and a large number of hydrophobic groups would lead to enhanced biocidal potency. The advent of dendrimers offers us the first-ever opportunity to achieve the desired high local density. We have demonstrated that dimethyl dodecyl ammonium chloride functionalized polypropylene imine dendrimers are over 100 times more potent than their small molecule ounterparts. In this study, quaternary ammonium, quaternary phosphonium, alkyl pyridinium and tertiary sulfonium salts based on polypropylene imine dendrimers have been synthesized and characterized. Their antimicrobial properties have been quantified with a novel bioluminescence method. The structure-activity relationship of these polycationic dendrimers has also been investigated to elucidate the molecular mechanism for the enhanced antimicrobial effects.

  13. 5,6-Dimethoxybenzofuran-3-one Derivatives: a Novel Series of Dual Acetylcholinesterase/Butyrylcholinesterase Inhibitors Bearing Benzyl Pyridinium Moiety

    Directory of Open Access Journals (Sweden)

    Mohammad Abdollahi

    2013-02-01

    Full Text Available Several studies have been focused on design and synthesis of multi-target anti Alzheimer compounds. Utilizing of the dual Acetylcholinesterase/Butyrylcholinesterase inhibitors has gained more interest to treat the Alzheimer’s disease. As a part of a research program to find a novel drug for treating Alzheimer disease, we have previously reported 6-alkoxybenzofuranone derivatives as potent acetylcholinesterase inhibitors. In continuation of our work, we would like to report the synthesis of 5,6-dimethoxy benzofuranone derivatives bearing a benzyl pyridinium moiety as dual Acetylcholinesterase/Butyrylcholinesterase inhibitors.MethodsThe synthesis of target compounds was carried out using a conventional method. Bayer-Villiger oxidation of 3,4-dimethoxybenzaldehyde furnished 3,4-dimethoxyphenol. The reaction of 3,4-dimethoxyphenol with chloroacetonitrile followed by treatment with HCl solution and then ring closure yielded the 5,6-dimethoxy benzofuranone. Condensation of the later compound with pyridine-4-carboxaldehyde and subsequent reaction with different benzyl halides afforded target compounds. The biological activity was measured using standard Ellman’s method. Docking studies were performed to get better insight into interaction of compounds with receptor.ResultsThe in vitro anti acetylcholinesterase/butyrylcholinesterase activity of compounds revealed that, all of the target compounds have good inhibitory activity against both Acetylcholinesterase/Butyrylcholinesterase enzymes in which compound 5b (IC50 = 52 ± 6.38nM was the most active compound against acetylcholinesterase. The same binding mode and interactions were observed for the reference drug donepezil and compound 5b in docking study.ConclusionsIn this study, we presented a new series of benzofuranone-based derivatives having pyridinium moiety as potent dual acting Acetylcholinesterase/Butyrylcholinesterase inhibitors.

  14. (E)-1-Methyl-4-[2-(1-naphth-yl)vin-yl]pyridinium 4-bromo-benzene-sulfonate.

    Science.gov (United States)

    Chantrapromma, Suchada; Chanawanno, Kullapa; Fun, Hoong-Kun

    2009-04-30

    In the title compound, C(18)H(16)N(+)·C(6)H(4)BrO(3)S(-), the cation exists in the E configuration and the whole mol-ecule of the cation is disordered with a refined site-occupancy ratio of 0.733 (1):0.267 (1). The naphthalene system is not planar, the inter-planar angle between the two aromatic rings being 5.0 (5)° for the major component and 5.7 (10)° for the minor component. The cation is twisted with dihedral angles between the pyridinium ring and the two aromatic rings of the naphthalene system of 56.3 (5) and 51.4 (5)° (for the major component) and 52.2 (11) and 53.4 (11)° (for the minor component). The pyridinium ring and the benzene ring of the anion are inclined to each other at inter-planar angles of 85.0 (4) and 71.5 (9)° for the major and minor components, respectively. In the crystal packing, the cations and anions are alternately arranged with the cations stacked in an anti-parallel manner along the c axis and the anions linked together into chains along the same direction. The cations are linked to the anions into chains along [102] by weak C-H⋯O inter-actions. The crystal structure is further stabilized by C-H⋯π inter-actions and π-π contacts, with Cg⋯Cg distances of 3.502 (9) and 3.698 (6) Å. A short Br⋯O contact [3.029 (4) Å] is also present.

  15. Mordant dyes as sensitisers in dye-sensitised solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Millington, Keith R.; Fincher, Keith W.; King, A. Lee [Commonwealth Scientific and Industrial Research Organisation, Textile and Fibre Technology, P.O. Box 21, Belmont, Vic. 3216 (Australia)

    2007-10-15

    Many mordant dyes commonly used in the textile industry form coordination complexes at the surface of nanocrystalline TiO{sub 2}. Dyes having a salicylate chelating group are particularly effective. Forty-nine commercial mordant dyes were studied as sensitisers in a non-optimised dye-sensitised solar cell (DSSC) and their performance compared to the N3 ruthenium complex. Although N3 produced the highest output, six mordant dyes produced photocurrents >0.2 mA. UV-visible spectra of the dye-complexed photoanodes suggest that some mordant dyes are more strongly bound to the TiO{sub 2} surface than N3. Photocatalytic oxidation of these dyes does not appear to occur in a DSSC environment. (author)

  16. Hair Dye and Hair Relaxers

    Science.gov (United States)

    ... Consumers Consumer Information by Audience For Women Hair Dye and Hair Relaxers Share Tweet Linkedin Pin it ... If you have a bad reaction to hair dyes and relaxers, you should: Stop using the product. ...

  17. Cosensitization of Ruthenium–Polypyridyl Dyes with Organic Dyes in Dye-sensitized Solar Cells

    National Research Council Canada - National Science Library

    Numata, Youhei; Zhang, Shufang; Yang, Xudong; Han, Liyuan

    2013-01-01

    Cosensitization, a technique involving sensitization of a metal-oxide semiconductor electrode with two or more different dyes, is a promising strategy to enhance light-harvesting capabilities of dye...

  18. OPTIMIZATION OF DYEING PARAMETERS TO DYE COTTON WITH CARROT EXTRACTION

    Directory of Open Access Journals (Sweden)

    MIRALLES Verónica

    2017-05-01

    Full Text Available Natural dyes derived from flora and fauna are believed to be safe because of non-toxic, non-carcinogenic and biodegradable nature. Furthermore, natural dyes do not cause pollution and waste water problems. Natural dyes as well as synthetic dyes need the optimum parameters to get a good dyeing. On some occasions, It is necessary the use of mordants to increase the affinity between cellulose fiber and natural dye, but there are other conditions to optimize in the dyeing process, like time, temperature, auxiliary porducts, etc. In addition, the optimum conditions are different depends on the type of dye and the fiber nature. The aim of this work is the use of carrot extract to dye cotton fabric by exhaustion at diverse dyeing conditions. Diffferent dyeing processes were carried out to study the effect of pH condition and the temperature, using 7, 6 and 4 pH values and 95 ºC and 130ºC for an hour. As a result some images of dyed samples are shown. Moreover, to evaluate the colour of each sample CIELAB parameters are analysed obtained by reflexion spectrophotometre. The results showed that the temperature used has an important influence on the colour of the dyed sample.

  19. Microfluidic Dye Lasers

    DEFF Research Database (Denmark)

    Kristensen, Anders; Balslev, Søren; Gersborg-Hansen, Morten

    2006-01-01

    A technology for miniaturized, polymer based lasers, suitable for integration with planar waveguides and microfluidic networks is presented. The microfluidic dye laser device consists of a microfluidic channel with an embedded optical resonator. The devices are fabricated in a thin polymer film...

  20. Levitated droplet dye laser

    DEFF Research Database (Denmark)

    Azzouz, H.; Alkafadiji, L.; Balslev, Søren

    2006-01-01

    a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating...

  1. for aqueous dye lasers

    Indian Academy of Sciences (India)

    2014-02-12

    Feb 12, 2014 ... polar molecule and possesses larger dipole moment at the excited state (S1), and stabi- lizes its energy by interacting with the polar and protic water solvent. The measured fluorescence spectra of RhB dye in ethanol, water and water with CB[7] (molar ratio. 1:5) in the temperature range 279–298 K were ...

  2. (MTT) dye reduction assay.

    African Journals Online (AJOL)

    to inhibit proliferation of HeLa cells was determined using the 3443- dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) dye reduction assay. Extracts from roots of Agathisanthemum bojeri, Synaptolepis kirkii and Zanha africana and the leaf extract of Physalis peruviana at a concentration of 10 pg/ml inhibited cell ...

  3. Magnetochemistry of the tetrahaloferrate (III) ions. 7. Crystal structure and magnetic ordering in (pyridinium){sub 3}Fe{sub 2}Br{sub 9}

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, C.B.; Shaviv, R.; Carlin, R.L. [Univ. of Illinois, Chicago, IL (United States)] [and others

    1994-07-06

    A monoclinic crystal structure was found by X-ray diffraction for bis [pyridinium tetrabromferrate(III)]-pyridinium bromide. The double salt contains two slightly distorted [FeBr{sub 4}]{sup -} tetrahedra, three pyridinium rings, and an uncoordinated halide in each asymmetric unit, as is characteristic of the A{sub 3}Fe{sub 2}X{sub 9} series of compounds. Unit cell parameters, monoclinic space group P2{sub 1}, are a = 7.656(3) {angstrom}, b = 14.237(5) {angstrom}, c = 13.725(5) {angstrom}, {beta} = 93.42(3){degrees}, and V = 1493(1) {angstrom}{sup 3}, using Mo K{alpha} radiation {lambda} = 0.710 69 {angstrom}, {rho}{sub calc} = 2.38 g cm{sup -3}, and Z = 2. The tetrahedra are aligned with their 3-fold axes parallel to the crystallographic c axis. Bond lengths (Fe-Br) range from 2.271(9) {angstrom} to 2.379(9) {angstrom} for the two different slightly distorted tetrahedral units. Magnetic susceptibility studies show that the material orders three-dimensionally at 7.4 {+-} 0.2 K. The data are compared to a HTS expansion of 1/{sub {chi}} for the S = 5/2 three-dimensional Heisenberg model antiferromagnet for a sc lattice with g = 1.98 and J/k{sub B} = -0.43 K. The specific heat measurements indicate two odd-shaped {lambda} features, at 7.3 and 8 K.

  4. Dye laser principles with applications

    CERN Document Server

    Duarte, Frank J; Liao, Peter F; Kelley, Paul

    1990-01-01

    A tutorial introduction to the field of dye lasers, Dye Laser Principles also serves as an up-to-date overview for those using dye lasers as research and industrial tools. A number of the issues discussed in this book are pertinent not only to dye lasers but also to lasers in general. Most of the chapters in the book contain problem sets that expand on the material covered in the chapter.Key Features* Dye lasers are among the most versatile and successful laser sources currently available in use Offering both pulsed and continuous-wave operation and tunable from the near ultraviole

  5. Plantas Tintureiras Dye Plants

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Serrano

    2008-12-01

    Full Text Available Existe uma vasta bibliografia, até ao séc. XVIII, sobre plantas produtoras de corantes naturais, sendo que apenas um número limitado foi utilizado no tingimento de têxteis antigos, devido à capacidade de resistência à lavagem e ao desvanecimento. O cultivo de plantas ou a sua existência no mundo silvestre tiveram uma enorme importância sócio-económica para muitas comunidades espalhadas pelo mundo e pelas intensas trocas comerciais que geraram. A extracção dos corantes era feita a partir de diferentes partes de plantas ou árvores. Nalgumas plantas eram utilizadas as folhas, enquanto noutras se aproveitavam as flores, as raízes, os frutos, troncos ou sementes. Os corantes podiam ser extraídos através de processos complexos que envolviam diversas operações como maceração, destilação, fermentação, decantação, precipitação, filtração, etc. Neste âmbito, são apresentadas algumas das plantas cultivadas em Portugal e em muitos outros países europeus e que foram usadas em tinturaria. Este trabalho pretende ser um contributo para obstar à perda de conhecimentos das condições de cultivo e da forma como se maximizava a produção de corantes.A vast bibliography exists, until the 18th cen-tury, on natural dyes obtained from plants, but only one limited number was used in the dyeing of old textiles, due to capacity of resistance to wash and light fading. The culture of plants or its existence in the wild world had an enormous economical importance for many communities spread for the world, and the intense commercial exchanges that had generated. The extraction of dyes was done from different parts of plants or trees. In some plants was used the leaves, others, only the roots, the fruits, trunks or seeds. The dyes could be extracted through complex processes that involved various operations as maceration, distillation, fermentation, decantation, precipitation, filtration, etc. In this scope, some of the plants cultivated in

  6. Dye purity and dye standardization for biological staining

    DEFF Research Database (Denmark)

    Lyon, H O

    2002-01-01

    This review starts with a short discussion of what is meant by a pure dye and a brief description of how dyes are produced. A listing of the types of impurities encountered in dyes is made, followed by technical investigations and assessments of dyes and their impurities including methods...... for separating, identifying and assaying dye components. In the second part of the review, descriptions are given of the standardized staining method approach using standard staining methods for assessing stains, and practical responses to stain impurity including commercial quality control, third-party quality...... control and standardization of reagents, protocols and documentation. Finally, reference is made to the current state of affairs in the dye field....

  7. Synthesis of azo pyridone dyes

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2011-01-01

    Full Text Available Over 50% of all colorants which are used nowdays are azo dyes and pigments, and among them arylazo pyridone dyes (and pigments have became of interest in last several decades due to the high molar extinction coefficient, and the medium to high light and wet fastness properties. They find application generally as disperse dyes. The importance of disperse dyes increased in the 1970s and 1980s due to the use of polyester and nylon as the main synthetic fibers. Also, disperse dyes were used rapidly since 1970 in inks for the heat-transfer printing of polyester. The main synthetic route for the preparation of azo dyes is coupling reaction between an aromatic diazo compound and a coupling component. Of all dyes manufactured, about 60% are produced by this reaction. Arylazo pyridone dyes can be prepared from pyridone moiety as a coupling component, where substituent can be on nitrogen, and diazonim salts which can be derived from different substituted anilines or other heterocyclic derivatives. In addition, arylazo dyes containing pyridone ring can be prepared from arylazo diketones or arylazo ketoesters (obtained by coupling β-diketones or β-ketoesters with diazonim salts by condensation with cyanoacetamide. Disazo dyes can be prepared by tetrazotizing a dianiline and coupling it with a pyridone or by diazotizing aniline and coupling it with a dipyridone. Trisazo dyes can be also prepared by diazotizing of aniline and coupling it with a tripyridone or by hexazotizing a trianiline and coupling it with a pyridone. The main goal of this paper is to give a brief review on the synthesis of arylazo pyridone dyes due to the lack of such reviews. In addition, some properties of arylazo pyridone dyes as light fastness and azo-hydrazon tautomerism are disccused.

  8. Dyeing fabrics with metals

    Science.gov (United States)

    Kalivas, Georgia

    2002-06-01

    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.

  9. HYDROXYANTHRAQUINONE DYES FROM PLANTS

    OpenAIRE

    Caro, Yanis; Petit, Thomas; Grondin, Isabelle; Fouillaud, Mireille; Dufossé, Laurent

    2017-01-01

    International audience; In the plant kingdom, numerous pigments have already been identified, but only a minority of them is allowed by legal regulations for textile dyeing, food coloring or cosmetic and pharmaceutics’ manufacturing. Anthraquinones, produced as secondary metabolites in plants, constitute a large structural variety of compounds among the quinone family. Derivatives that contain hydroxyl groups, namely hydroxy-anthraquinones, are colored. They have attracted the attention of ma...

  10. WATERLESS DYEING [REVIEW

    OpenAIRE

    DEVRENT Nalan

    2015-01-01

    The textile industry is believed to be one of the biggest consumers of water. Water consumption and exhaustion in dyeing textile materials in conventional methods is an important environmental problem. The cost of waste water treatment will cause a prominent problem in the future as it does today. Increasing consideration of ecologic consequences of industrial processes as well as legislation enforcing the avoidance of environmental problems have caused a reorientation of thinking and promote...

  11. Novel pyridinium-based tags: synthesis and characterization for highly efficient analysis of thiol-containing peptides by mass spectrometry.

    Science.gov (United States)

    Qiao, Xiaoqiang; Yang, Yanjun; Liu, Shijia; Chen, Shiheng; Wang, Xin; Li, Guangyue; Yan, Hongyuan; Yang, Xun

    2015-01-21

    In this study, a novel type of pyridinium-based tags, 1-[3-[(2-iodo-1-oxoethyl)amino]propyl]-4-methylpyridinium bromide (IMP) and 1-[3-[(2-iodo-1-oxoethyl)amino]propyl]-4-propylpyridinium bromide (IPP), were designed, synthesized, and applied to the derivatization of thiol-containing peptides. With model peptides as the sample, the labeling efficiency and the stability of the peptide derivatives were investigated. The results indicate that nearly 100% derivatization yield was achieved with the developed tags and the peptide derivatives were stable at room temperature for at least one week. Furthermore, improved ionization efficiency and increased charge states were achieved via both matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MS) and electrospray ionization (ESI) MS, of which IPP exhibited the more obvious improvement of ionization efficiency. Further analysis of tryptic digests of bovine serum albumin (BSA) and α-transferrin, showed that increased identification efficiency of the thiol-containing peptides was achieved by combination with IMP or IPP derivatization. For example, the identification efficiency of the thiol-containing peptides of α-transferrin increased more than 42% upon combination with the IMP or IPP derivatives. We anticipate the novel tags are promising for highly efficient thiol-containing peptide identification in proteome research, especially for low concentrations.

  12. Pyridinium oximes: rationale for their selection as causal antidotes against organophosphate poisonings and current solutions for auto-injectors.

    Science.gov (United States)

    Stojiljković, Milos P; Jokanović, Milan

    2006-12-01

    During the last five decades, five pyridinium oximes were found to be worthy of use as antidotes against nerve agents in humans: pralidoxime, in a form of chloride or PAM-2 Cl and mesylate or P2S (against sarin, cyclosarin and VX), trimedoxime or TMB-4 and obidoxime or LüH-6 (both against tabun, sarin and VX), HI-6 (against sarin, soman, cyclosarin and VX) and HLö-7 (against all the five nerve agents). In order to provide the auto-injector with the best and most potent acetylcholinesterase reactivator, the Defence Research and Development Canada (DRDC) received in the 1990s a core funding from the federal government's CBRN research and Technology Initiative (CRTI). Its ultimate result should be three products: (1) 3-in-1 auto-injector (atropine, HI-6 dimethanesulphonate and avizafone, as anticonvulsant), (2) 2-in-1 auto-injector (atropine and HI-6 dimethanesulphonate) and (3) HI-6 dimethanesulphonate in a vial for administration by the medically trained personnel. Previous experimental and clinical experience suggests that, among the oximes mentioned, only trimedoxime and obidoxime can be used for acetylcholinesterase reactivation and antidotal protection against most of the organophosphorus insecticides. The search for an "omnipotent" oxime, effective in reactivation of AChE inhibited with both nerve agents and organophosphorus insecticides, is still ongoing.

  13. Aggregation behavior and antimicrobial activity of ester-functionalized imidazolium- and pyridinium-based ionic liquids in aqueous solution.

    Science.gov (United States)

    Garcia, M Teresa; Ribosa, Isabel; Perez, Lourdes; Manresa, Angeles; Comelles, Francesc

    2013-02-26

    Two series of long chain imidazolium- and pyridinium-based ionic liquids containing an ester functional group in the alkyl side chain, 3-methyl-1-alkyloxycarbonylmethylimidazolium bromides (C(n)EMeImBr) and 1-alkyloxycarbonylmethylpyridinium bromides (C(n)EPyrBr), were synthesized and their thermal stability, aggregation behavior in aqueous medium, and antimicrobial activity investigated. The introduction of an ester group decreased the thermal stability of the functionalized ILs compared to simple alkyl chain containing ILs (1-alkyl-3-methylimidazolium bromides and 1-alkylpyridinium bromides). Tensiometry, conductimetry, and spectrofluorimetry were applied to study the self-aggregation of the amphiphilic ILs in aqueous solution. The ILs investigated displayed surface activity and the characteristic chain length dependence of the micellization process of surfactants. As compared to simple alkyl chain containing ILs bearing the same hydrocarbon chain, ester-functionalized ILs possess higher adsorption efficiency (pC(20)) and significantly lower critical micelle concentration (cmc) and surface tension at the cmc (γ(cmc)), indicating that the incorporation of an ester group promotes adsorption at the air/water interface and micelle formation. The antimicrobial activity was evaluated against Gram-negative and Gram-positive bacteria and fungi. ILs containing more than eight carbon atoms in the alkyl chain showed antimicrobial activity. Their efficiency as antimicrobial agents increased with the hydrophobicity of the amphiphilic cation being the C(12) homologous the most active compounds. The incorporation of an ester group particularly increased the biological activity against fungi.

  14. Cold Pad-Batch dyeing method for cotton fabric dyeing with reactive dyes using ultrasonic energy.

    Science.gov (United States)

    Khatri, Zeeshan; Memon, Muhammad Hanif; Khatri, Awais; Tanwari, Anwaruddin

    2011-11-01

    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 ΔE (CMC) for the proposed method, were found within close proximity to the conventionally dyed sample. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Self-assembly of [UO{sub 2}X{sub 4}]{sup 2−} (X=Cl, Br) dianions with γ substituted pyridinium cations: Structural systematics and fluorescence properties

    Energy Technology Data Exchange (ETDEWEB)

    Surbella, Robert G.; Andrews, Michael B.; Cahill, Christopher L., E-mail: cahill@gwu.edu

    2016-04-15

    Room temperature self-assembly of [UO{sub 2}X{sub 4}]{sup 2−} (X=Cl, Br) with γ substituted pyridinium cations has resulted in the formation of twelve compounds that were studied via single crystal X-ray diffraction and fluorescence spectroscopy. Systematic variation of electron donating groups on the pyridinium species is shown to influence the presence and/or strength of various supramolecular synthons, including hydrogen bonding and pi interactions. Combinations of such non-covalent interactions (NCIs) have given rise to a range of supramolecular assemblies, and are shown to influence uranyl emission by way of second sphere coordination to equatorial ligands. - Graphical abstract: Supramolecular assembly of the [UO{sub 2}Cl{sub 4}]{sup 2−} dianion with pyridinium cations is a viable synthetic route to the growth of uranyl containing single crystals.

  16. Natural dyes and dyeing techniques used by craftswomen in the ...

    African Journals Online (AJOL)

    A survey of the plants used by craftswomen in the northern Hhohho region of Swaziland to dye craft materials was conducted. Nineteen plants were identified and details concerning the part of the plant used, the time of year it was harvested and the colour obtained were documented. The techniques used during the dyeing ...

  17. Treatment of dyeing wastewater including reactive dyes (Reactive ...

    African Journals Online (AJOL)

    The decolourisation potential of growing Rhizopus arrhizus fungal strain in liquid medium containing thiamine was investigated for the removal of anionic reactive dyes such as Reactive Red RB (RR), Reactive Black B (RBB) and Remazol Blue (RB) and a cationic basic dye Methylene Blue (MB). To determine the optimal ...

  18. Metal Complex Dyes for Dye-Sensitized Solar Cells: Recent ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 9. Metal Complex Dyes for Dye-Sensitized Solar Cells: ... Author Affiliations. N Sekar1 Vishal Y Gehlot. Dyestuff Technology Department Institute of Chemical Technology (Formerly UDCT) Nathalal Parekh Marg Matunga Mumbai 400 019, India.

  19. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available 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.

  20. Dye solar cell research

    CSIR Research Space (South Africa)

    Cummings, F

    2009-11-01

    Full Text Available Cummings Energy and Processes Materials Science and Manufacturing Council for Scientific and Industrial Research P.O. Box 395 Pretoria 0001, South Africa 27 November 2009 CONTENT head2rightBackground head2rightCSIR Dye Solar Cell Research head2... rightCollaborations and Links © CSIR 2007 www.csir.co.za head2rightAcknowledgements BACKGROUND head2rightSA is dry: Annual rainfall average of 450 mm compared with a world average of 860 mm head2rightOn upside, we have some...

  1. An Eco-Friendly Ultrasound-Assisted Synthesis of Novel Fluorinated Pyridinium Salts-Based Hydrazones and Antimicrobial and Antitumor Screening

    Directory of Open Access Journals (Sweden)

    Nadjet Rezki

    2016-05-01

    Full Text Available The present work reports an efficient synthesis of fluorinated pyridinium salts-based hydrazones under both conventional and eco-friendly ultrasound procedures. The synthetic approach first involves the preparation of halogenated pyridinium salts through the condensation of isonicotinic acid hydrazide (1 with p-fluorobenzaldehyde (2 followed by the nucleophilic alkylation of the resulting N-(4-fluorobenzylideneisonicotinohydrazide (3 with a different alkyl iodide. The iodide counteranion of 5–10 was subjected to an anion exchange metathesis reaction in the presence of an excess of the appropriate metal salts to afford a new series of fluorinated pyridinium salts tethering a hydrazone linkage 11–40. Ultrasound irradiation led to higher yields in considerably less time than the conventional methods. The newly synthesized ILs were well-characterized with FT-IR, 1H NMR, 13C NMR, 11B, 19F, 31P and mass spectral analyses. The ILs were also screened for their antimicrobial and antitumor activities. Within the series, the salts tethering fluorinated counter anions 11–13, 21–23, 31–33 and 36–38 were found to be more potent against all bacterial and fungal strains at MIC 4–8 µg/mL. The in vitro antiproliferative activity was also investigated against four tumor cell lines (human ductal breast epithelial tumor T47D, human breast adenocarcinoma MCF-7, human epithelial carcinoma HeLa and human epithelial colorectal adenocarcinoma Caco-2 using the MTT assay, which revealed that promising antitumor activity was exhibited by compounds 5, 12 and 14.

  2. Trabecular microfracture and the influence of pyridinium and non-enzymatic glycation-mediated collagen cross-links.

    Science.gov (United States)

    Hernandez, Christopher J; Tang, Simon Y; Baumbach, Bethany M; Hwu, Paul B; Sakkee, A Nico; van der Ham, Frits; DeGroot, Jeroen; Bank, Ruud A; Keaveny, Tony M

    2005-12-01

    The propensity of individual trabeculae to fracture (microfracture) may be important clinically since it could be indicative of bone fragility. Whether or not an overloaded trabecula fractures is determined in part by its structural ductility, a mechanical property that describes how much deformation a trabecula can sustain. The overall goal of this study was to determine the structural ductility of individual trabeculae and the degree to which it is influenced by pyridinium and non-enzymatic collagen cross-links. Vertically oriented rodlike trabeculae were taken from the thoracic vertebral bodies of 32 cadavers (16 male and 16 female, 54 - 94 years of age). A total of 221 trabeculae (4 - 9 per donor) were tested to failure in tension using a micro-tensile loading device. A subset of 76 samples was analyzed to determine the concentration of hydroxylysyl-pyridinoline (HP) and lysyl-pyridinoline (LP) cross-links as well as pentosidine, a marker of non-enzymatic glycation. Structural ductility (defined as the ultimate strain of the whole trabecula) ranged from 1.8% to 20.2% strain (8.8 +/- 3.7%, mean +/- SD) and did not depend on age (P = 0.39), sex (P = 0.57), or thickness of the sample at the point of failure (P = 0.36). Pentosidine was the only marker of collagen cross-linking measured that was found to be correlated with structural ductility (P = 0.01) and explained about 9% of the observed variance. We conclude that the ductility of individual trabeculae varies tremendously, can be substantial, and is weakly influenced by non-enzymatic glycation.

  3. Effect of hormone replacement therapy on the bone mass and urinary excretion of pyridinium cross-links

    Directory of Open Access Journals (Sweden)

    Dolores Perovano Pardini

    2000-01-01

    Full Text Available CONTEXT: The menopause accelerates bone loss and is associated with an increased bone turnover. Bone formation may be evaluated by several biochemical markers. However, the establishment of an accurate marker for bone resorption has been more difficult to achieve. OBJECTIVE: To study the effect of hormone replacement therapy (HRT on bone mass and on the markers of bone resorption: urinary excretion of pyridinoline and deoxypyridinoline. DESIGN: Cohort correlational study. SETTING: Academic referral center. SAMPLE: 53 post-menopausal women, aged 48-58 years. MAIN MEASUREMENTS: Urinary pyr and d-pyr were measured in fasting urine samples by spectrofluorometry after high performance liquid chromatography and corrected for creatinine excretion measured before treatment and after 1, 2, 4 and 12 months. Bone mineral density (BMD was measured by dual energy X-ray absorptiometry (DEXA before treatment and after 12 months of HRT. RESULTS: The BMD after HRT was about 4.7% (P < 0.0004; 2% (P < 0.002; and 3% (P < 0.01 higher than the basal values in lumbar spine, neck and trochanter respectively. There were no significant correlations between pyridinium cross-links and age, weight, menopause duration and BMD. The decrease in pyr and d-pyr was progressive after HRT, reaching 28.9% (P < 0.0002, and 42% (P < 0.0002 respectively after 1 year. CONCLUSIONS: Urinary pyridinoline and deoxypyridinoline excretion decreases early in hormone replacement therapy, reflecting a decrease in the bone resorption rate, and no correlation was observed with the bone mass evaluated by densitometry.

  4. Diode pumped tunable dye laser

    Science.gov (United States)

    Burdukova, O.; Gorbunkov, M.; Petukhov, V.; Semenov, M.

    2017-03-01

    A wavelength-tunable dye laser pumped by blue laser diodes (λ =445 nm) in a 200 ns pulsed mode has been developed. We used a 3-mirror cavity with transverse excitation and total internal reflection of laser beam in the active element. Tuning curves for 8 dyes in benzyl alcohol were measured in the range of 506-700 nm. Four dyes have their tuning range more than 60 nm, which is comparable to the tuning ranges of other dye lasers pumped by more expensive sources. The output energy obtained at the generation maximum of both DCM and coumarin 540A dyes was approximately 130 nJ while the pump energy was 2400 nJ.

  5. Quantitative comparison of long-wavelength Alexa Fluor dyes to Cy dyes: fluorescence of the dyes and their bioconjugates.

    Science.gov (United States)

    Berlier, Judith E; Rothe, Anca; Buller, Gayle; Bradford, Jolene; Gray, Diane R; Filanoski, Brian J; Telford, William G; Yue, Stephen; Liu, Jixiang; Cheung, Ching-Ying; Chang, Wesley; Hirsch, James D; Beechem, Joseph M; Haugland, Rosaria P; Haugland, Richard P

    2003-12-01

    Amine-reactive N-hydroxysuccinimidyl esters of Alexa Fluor fluorescent dyes with principal absorption maxima at about 555 nm, 633 nm, 647 nm, 660 nm, 680 nm, 700 nm, and 750 nm were conjugated to antibodies and other selected proteins. These conjugates were compared with spectrally similar protein conjugates of the Cy3, Cy5, Cy5.5, Cy7, DY-630, DY-635, DY-680, and Atto 565 dyes. As N-hydroxysuccinimidyl ester dyes, the Alexa Fluor 555 dye was similar to the Cy3 dye, and the Alexa Fluor 647 dye was similar to the Cy5 dye with respect to absorption maxima, emission maxima, Stokes shifts, and extinction coefficients. However, both Alexa Fluor dyes were significantly more resistant to photobleaching than were their Cy dye counterparts. Absorption spectra of protein conjugates prepared from these dyes showed prominent blue-shifted shoulder peaks for conjugates of the Cy dyes but only minor shoulder peaks for conjugates of the Alexa Fluor dyes. The anomalous peaks, previously observed for protein conjugates of the Cy5 dye, are presumably due to the formation of dye aggregates. Absorption of light by the dye aggregates does not result in fluorescence, thereby diminishing the fluorescence of the conjugates. The Alexa Fluor 555 and the Alexa Fluor 647 dyes in protein conjugates exhibited significantly less of this self-quenching, and therefore the protein conjugates of Alexa Fluor dyes were significantly more fluorescent than those of the Cy dyes, especially at high degrees of labeling. The results from our flow cytometry, immunocytochemistry, and immunohistochemistry experiments demonstrate that protein-conjugated, long-wavelength Alexa Fluor dyes have advantages compared to the Cy dyes and other long-wavelength dyes in typical fluorescence-based cell labeling applications.

  6. Solvatochromism in a pyridinium cyclopentadienylide: insights from a sequential Car-Parrinello QM/MM and TD-DFT/semicontinuum approach.

    Science.gov (United States)

    Murugan, N Arul

    2014-07-03

    Understanding the working mechanism and establishing structure-property relationships for optical probes is an essential step to develop design principles for novel molecular probes. Here we study optical properties of a small-sized dielectric probe, namely, 4-carbamido pyridinium cyclopentadienylide (CPYC) in benzene and in water solvents using a sequential approach. In particular, the structure modeling has been carried out using a Car-Parrinello hybrid QM/MM molecular dynamics approach, while the excitation energies were computed using time dependent density functional theory. To incorporate the solvent effect either a polarizable continuum model or a semicontinuum description was employed. The molecular dipole moment of CPYC in water is more than two times larger than in benzene solvent. The positive and negative charges tend to accumulate on pyridinium and cyclopentadienylide rings, respectively, with increasing solvent polarity. Significant solvent-induced geometrical changes have been reported in CPYC and this contributes to a significant red shift in spectra. Even though the absorption maxima for CPYC in benzene and water solvents were underestimated, the solvatochromic shift has been reproduced in good agreement with experiments. We also report that CPYC can be used as a two photon probe.

  7. Aspects of nonviral gene therapy: correlation of molecular parameters with lipoplex structure and transfection efficacy in pyridinium-based cationic lipids.

    Science.gov (United States)

    Parvizi, Paria; Jubeli, Emile; Raju, Liji; Khalique, Nada Abdul; Almeer, Ahmed; Allam, Hebatalla; Manaa, Maryem Al; Larsen, Helge; Nicholson, David; Pungente, Michael D; Fyles, Thomas M

    2014-01-30

    This study seeks correlations between the molecular structures of cationic and neutral lipids, the lipid phase behavior of the mixed-lipid lipoplexes they form with plasmid DNA, and the transfection efficacy of the lipoplexes. Synthetic cationic pyridinium lipids were co-formulated (1:1) with the cationic lipid 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine (EPC), and these lipids were co-formulated (3:2) with the neutral lipids 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) or cholesterol. All lipoplex formulations exhibited plasmid DNA binding and a level of protection from DNase I degradation. Composition-dependent transfection (beta-galactosidase and GFP) and cytotoxicity was observed in Chinese hamster ovarian-K1 cells. The most active formulations containing the pyridinium lipids were less cytotoxic but of comparable activity to a Lipofectamine 2000™ control. Molecular structure parameters and partition coefficients were calculated for all lipids using fragment additive methods. The derived shape parameter values correctly correlated with observed hexagonal lipid phase behavior of lipoplexes as derived from small-angle X-ray scattering experiments. A transfection index applicable to hexagonal phase lipoplexes derived from calculated parameters of the lipid mixture (partition coefficient, shape parameter, lipoplex packing) produced a direct correlation with transfection efficiency. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Heterobifunctional Dyes: Highly Fluorescent Linkers Based on Cyanine Dyes

    OpenAIRE

    Wycisk, Virginia; Achazi, Katharina; Hirsch, Ole; Kuehne, Christian; Dernedde, Jens; Haag, Rainer; Licha, Kai

    2017-01-01

    Abstract Herein, we present a new synthetic route to cyanine?based heterobifunctional dyes and their application as fluorescent linkers between polymers and biomolecules. The synthesized compounds, designed in the visible spectral range, are equipped with two different reactive groups for highly selective conjugation under physiological conditions. By applying indolenine precursors with functionalized benzenes, we achieved water?soluble asymmetric cyanine dyes bearing maleimido and N?hydroxys...

  9. Survery on Actual Conditions of Food Dyes

    OpenAIRE

    佐藤, ひろみ

    1981-01-01

    Many food dyes are widely used as food additives in Japan, and many investigations have been pointed the problems of safety of these food dyes used in Japanese food. There are two types of commercial food dyes, one is synthetic dyes and the other is natural dyes.Recently Japanese food is not stained so colourfully, but it is stained faintly in colour near to natural food by using of mixed synthetic dyes. On their hand, many consumers have a tendency to prefer natural food dyes because they ha...

  10. Natural dyes as photosensitizers for dye-sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Sancun; Wu, Jihuai; Huang, Yunfang; Lin, Jianming [Institute of Materials Physical Chemistry, Huaqiao University, Quanzhou, Fujian 362021 (China)

    2006-02-15

    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 I{sub SC} from 1.142mA to 0.225mA, the V{sub OC} from 0.551V to 0.412V, the fill factor from 0.52 to 0.63, and P{sub max} from 58{mu}W to 327{mu}W were obtained from the DSC sensitized with natural dye extracts. In the extracts of natural fruit, leaves and flower chosen, the black rice extract performed the best photosensitized effect, which was due to the better interaction between the carbonyl and hydroxyl groups of anthocyanin molecule on black rice extract and the surface of TiO{sub 2} porous film. The blue-shift of absorption wavelength of the black rice extract in ethanol solution on TiO{sub 2} film and the blue-shift phenomenon from absorption spectrum to photoaction spectrum of DSC sensitized with black rice extract are discussed in the paper. Because of the simple preparation technique, widely available and low cheap cost natural dye as an alternative sensitizer for dye-sensitized solar cell is promising. (author)

  11. Diffusion dynamics in microfluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Niels Asger

    2007-01-01

    We have investigated the bleaching dynamics that occur in opto-fluidic dye lasers, where the liquid laser dye in a channel is locally bleached due to optical pumping. Our studies suggest that for micro-fluidic devices, the dye bleaching may be compensated through diffusion of dye molecules alone....... By relying on diffusion rather than convection to generate the necessary dye replenishment, our observation potentially allows for a significant simplification of opto-fluidic dye laser device layouts, omitting the need for cumbersome and costly external fluidic handling or on-chip micro-fluidic pumping...

  12. Aging Effects on the Properties of Imidazolium-, Quaternary Ammonium-, Pyridinium-, and Pyrrolidinium-Based Ionic Liquids Used in Fuel and Energy Production

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Elise B.; Smith, L. Taylor; Williamson, Tyler K.; Kendrick, Sarah E.

    2013-11-21

    Ionic liquids (ILs) are often cited for their excellent thermal stability, a key property for their use as solvents and in the chemical processing of biofuels. However, there has been little supporting data on the long-term aging effect of the temperature on these materials. Imizadolium-, quaternary ammonium-, pyridinium-, and pyrrolidnium-based ILs with the bis(trifluoromethylsulfonyl)imide and bis(perfluoroethylsulfonyl)imide anions were aged for 2520 h (15 weeks) at 200 °C in air to determine the effects of an oxidizing environment on their chemical structure and thermal stability over time. Finally, it was found that the minor changes in the cation chemistry could greatly affect the properties of the ILs over time.

  13. Palladium Nanoparticles Immobilized on Poly(vinyl chloride-Supported Pyridinium as an Efficient and Recyclable Catalyst for Suzuki-Miyaura Cross-Coupling Reaction

    Directory of Open Access Journals (Sweden)

    Bo Zhou

    2011-01-01

    Full Text Available The palladium nanoparticles immobilized on the polymeric surface of poly(vinyl chloride-supported pyridinium (PVC-Py-Pd0 were achieved by a simple procedure by applying the corresponding functionalized polymer and palladium chloride in ethanol solution. The as-prepared catalyst (PVC-Py-Pd0 was found to be air and moisture stable and exhibits significant catalytic activity for Suzuki-Miyaura cross-coupling reaction of various aryl halides and phenylboronic acid under milder operating conditions. The procedure presented here showed several merits such as short reaction time, simple experimental and isolated procedure and excellent yields of products. Furthermore, the catalyst can be easily recovered and reused for at least six times with consistent activities.

  14. Laser dye toxicity, hazards, and recommended controls

    Energy Technology Data Exchange (ETDEWEB)

    Mosovsky, J.A.

    1983-05-06

    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.

  15. Fruit based Dye Sensitized Solar Cells

    Science.gov (United States)

    Ung, M. C.; Sipaut, C. S.; Dayou, J.; Liow, K. S.; Kulip, J.; Mansa, R. F.

    2017-07-01

    Dye Sensitized Solar Cell (DSSC) was first discovered in 1991 by O’regan and Gratzel. This new type of solar cell was reported to have lower production cost with efficiency as high as 12% which is comparable to conventional silicon solar cell. Initially, it uses ruthenium dye as light sensitizer for the operation. However, DSSC with ruthenium dyes are facing environment friendly issues due to the toxic chemicals and costly purification in processing ruthenium dye. Regardless of the poor performance in DSSC, natural dyes which are easy to prepare, cheap and environmental friendly still appear to be an alternative as dye sensitizer. In this study, dye sensitized solar cells (DSSCs) were fabricated using anthocyanin source dyes extracted from several local fruits. All the extracts absorb a wide range of the visible light and ultraviolet spectrum. Therefore, all of the natural dyes show light absorption properties which is important for a dye sensitizer. A DSSC is comprised of conductive substrate, nanoporous semiconductor TiO2 layer, dye sensitizer, electrolyte with redox couple and a counter electrode with catalyst. In this study, the effect of different light source and different counter electrode are been investigated. However, it is vital to know that further research need to do more on the locally Borneo sourced dyes to evaluate and enhance their performance in Dye Sensitized Solar Cell.

  16. Dye Sensitized Tandem Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Barber, Greg D.

    2009-12-21

    This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

  17. Optofluidic ring resonator dye lasers

    Science.gov (United States)

    Sun, Yuze; Suter, Jonathan D.; Fan, Xudong

    2010-02-01

    We overview the recent progress on optofluidic ring resonator (OFRR) dye lasers developed in our research group. The fluidics and laser cavity design can be divided into three categories: capillary optofluidic ring resonator (COFRR), integrated cylindrical optofluidic ring resonator (ICOFRR), and coupled optofluidic ring resonator (CpOFRR). The COFRR dye laser is based on a micro-sized glass capillary with a wall thickness of a few micrometers. The capillary circular cross-section forms the ring resonator and supports the whispering gallery modes (WGMs) that interact evanescently with the gain medium in the core. The laser cavity structure is versatile to adapt to the gain medium of any refractive index. Owing to the high Q-factor (>109), the lasing threshold of 25 nJ/mm2 is achieved. Besides directly pump the dye molecules, lasing through fluorescence resonance energy transfer (FRET) between the donor and acceptor dye molecules is also studied in COFRR laser. The energy transfer process can be further controlled by designed DNA scaffold labeled with donor/acceptor molecules. The ICOFRR dye laser is based on a cylindrical ring resonator fused onto the inner surface of a thick walled glass capillary. The structure has robust mechanical strength to sustain rapid gain medium circulation. The CpOFRR utilizes a cylindrical ring resonator fused on the inner surface of the COFRR capillary. Since the capillary wall is thin, the individual WGMs of the cylindrical ring resonator and the COFRR couples strongly and forms Vernier effect, which provides a way to generate a single mode dye laser.

  18. Acid-base indicator properties of dyes from local plants I: dyes from ...

    African Journals Online (AJOL)

    In strong acid/strong base titrations using the dyes as indicators, the end-points obtained agreed well with those obtained using conventional indicators. The dyes were found not suitable for weak acid/weak base titrations. The Ka of the purple dye from Basella alba was of the order of 10-5 while that of the red dye from H.

  19. Dye solubility in supercritical carbon dioxide fluid

    Directory of Open Access Journals (Sweden)

    Yan Jun

    2015-01-01

    Full Text Available Supercritical carbon dioxide fluid is an alternative solvent for the water of the traditional dyeing. The solubility of dyestuff affects greatly the dyeing process. A theoretical model for predicting the dye solubility is proposed and verified experimentally. The paper concludes that the pressure has a greater impact on the dyestuff solubility than temperature, and an optimal dyeing condition is suggested for the highest distribution coefficient of dyestuff.

  20. Effect of dye structure and redox mediators on anaerobic azo and anthraquinone dye reduction

    Directory of Open Access Journals (Sweden)

    Mayara Carantino Costa

    2012-01-01

    Full Text Available We investigated the biological decolourisation of dyes with different molecular structures. The kinetic constant values (k1 achieved with azo dye Reactive Red 120 were 7.6 and 10.1 times higher in the presence of RM (redox mediators AQDS and riboflavin, respectively, than the assays lacking RM. The kinetic constant achieved with the azo dye Congo Red was 42 times higher than that obtained with the anthraquinone dye Reactive Blue 4. The effect of RM on dye reduction was more evident for azo dyes resistant to reductive processes, and ineffective for anthraquinone dyes because of the structural stability of the latter.

  1. Characteristics of nanostructure dye-sensitized solar cells using food dyes

    Science.gov (United States)

    Hosseinnezhad, M.; Rouhani, S.

    2016-01-01

    Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TiO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

  2. COLOR POLLUTION CONTROL IN TEXTILE DYEING INDUSTRY ...

    African Journals Online (AJOL)

    a

    The exhausted dye bath wastes still contain significant quantities of coloring matter and impart color to the receiving water bodies. In addition to imparting color dye baths also contribute to organic and inorganic load of the receiving streams. Dye bath wastes are typically characterized by residual color, alkaline pH (mostly), ...

  3. Highly Fluorescent dye-nanoclay Hybrid Materials Made from Different Dye Classes.

    Science.gov (United States)

    Grabolle, Markus; Starke, Marian; Resch-Genger, Ute

    2016-04-12

    Nanoclays like laponites, which are commercially avaible in large quantities for a very moderate price, provide a facile solubilization strategy for hydrophobic dyes without the need for chemical functionalization and can act as a carrier for a high number of dye molecules. This does not require reactive dyes, amplifies fluorescence signals from individual emitters due to the high number of dyes molecules per laponite disk, and renders hydrophobic emitters applicable in aqueous environments. Aiming at the rational design of bright dye-loaded nanoclays as a new class of fluorescent reporters for bioanalysis and material sciences and the identification of dye structure-property relationships, we screened a series of commercial fluorescent dyes, differing in dye class, charge, and character of the optical transitions involved, and studied the changes of their optical properties caused by clay adsorption at different dye loading concentrations. Upon the basis of our dye loading density-dependent absorption and fluorescence measurements with S2105 and Lumogen F Yellow 083, we could identify two promising dye-nanoclay hybrid materials that reveal high fluorescence quantum yields of the nanoclay-adsorbed dyes of at least 0.20 and low dye self-quenching even at high dye-loading densities of up to 50 dye molecules per laponite platelet.

  4. Waste Water Treatment of Dye Contamination

    OpenAIRE

    Pattana Boonyaprapa

    2009-01-01

    The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment s...

  5. Contact urticaria to cosmetic and industrial dyes.

    Science.gov (United States)

    Davari, P; Maibach, H I

    2011-01-01

    Contact urticaria (CU) defines the weal-and-flare reaction that occurs after external cutaneous contact with a causative agent. These reactions often cause discomfort for patients, affect their quality of life, and in severe cases may be life-threatening. Some dyes are known to be urticariogens. Many people have daily exposure to these urticariogens, because of the widespread use of dyes, for example in textiles, cosmetics and foods. We reviewed industrial and cosmetic dyes such as hair dyes, basic blue 99 dye, patent blue dyes, henna, red dyes, curcumin and reactive dyes, which can potentially cause CU. Overall, the reported cases of CU lacked appropriate controls. Hair-dye constituents such as preservatives and intensifiers may play an important role as causative agents of CU. We recommend appropriate protection guidelines to reduce the incidence of CU in high-risk groups such as hairdressers, dye-factory workers or workers in dye-related industries. © 2010 The Author(s). Journal compilation © 2010 British Association of Dermatologists.

  6. Anaphylaxis to annatto dye: a case report.

    Science.gov (United States)

    Nish, W A; Whisman, B A; Goetz, D W; Ramirez, D A

    1991-02-01

    Annatto dye is an orange-yellow food coloring extracted from the seeds of the tree Bixa orellana. It is commonly used in cheeses, snack foods, beverages, and cereals. Previously reported adverse reactions associated with annatto dye have included urticaria and angioedema. We present a patient who developed urticaria, angioedema, and severe hypotension within 20 minutes following ingestion of milk and Fiber One cereal, which contained annatto dye. Subsequent skin tests to milk, wheat, and corn were negative. The patient had a strong positive skin test to annatto dye, while controls had no response. The nondialyzable fraction of annatto dye on SDS-PAGE demonstrated two protein staining bands in the range of 50 kD. Immunoblotting demonstrated patient IgE-specific for one of these bands, while controls showed no binding. Annatto dye may contain contaminating or residual seed proteins to which our patient developed IgE hypersensitivity. Annatto dye is a potential rare cause of anaphylaxis.

  7. Interaction between humic acids and anthraquinone dyes

    Energy Technology Data Exchange (ETDEWEB)

    Shinozuka, N.; Lee, C. (The University of Tokyo, Tokyo (Japan). Institute of Industrial Science)

    1991-08-20

    Interactions between humic acids and anthraquinone disperse-dyes were studied. A humic acid extracted from a marine sediment and a commercial one were used to solubilized dyes sparingly soluble in water. The dye solubility in humic acid solution increases with humic acid concentration and enhancement was marked for solution of Aldrich humic acid. The addition of salts decreased the solubility of the dye. But the effects were complicated. Dye solubility increased with temperature. Especially, in the case of a 0.1% solution of marine humic acid at high temperature, the solubility increased. The spectrum of the dye were changed by solubilization in humic acid solution, and a twin peak characteristics of 1,4-isomers of polyaminoanthraquinone disappeared and a broad peak appeared. The dye solubilized by humic acid may thus possibly exist as a solid state as a deposit on quartz. 23 refs., 3 figs., 3 tabs.

  8. Advanced oxidation of acid and reactive dyes

    DEFF Research Database (Denmark)

    Arslan-Alaton, I.; Gursoy, B.H.; Schmidt, Jens Ejbye

    2008-01-01

    The effect of untreated and Fenton-treated acid dyes (C.I. Acid Red 183 and C.I. Acid Orange 51) and a reactive dye (C.I. Reactive Blue 4) on aerobic, anoxic and anaerobic processes was investigated. The optimum Fe2+:H2O2 molar ratio was selected as 1:5 (4:hsp sp="0.25" mM:20:hsp sp="0.25"m...... for the untreated blue, red and orange dyes, respectively. The inhibitory effect of the blue reactive dye on methane production was ∼21% after Fenton treatment. Neither untreated nor treated dyes exhibited an inhibitory effect on denitrification. Aerobic glucose degradation was inhibited by 23-29% by untreated dyes......, whereas Fenton-treated dyes had no inhibitory effect on aerobic glucose degradation....

  9. Hydrogen bonding, π-π stacking and van der Waals forces-dominated layered regions in the crystal structure of 4-amino-pyridinium hydrogen (9-phosphono-non-yl)phospho-nate.

    Science.gov (United States)

    van Megen, Martin; Reiss, Guido J; Frank, Walter

    2016-10-01

    The asymmetric unit of the title mol-ecular salt, [C5H7N2+][(HO)2OP(CH2)9PO2(OH)-], consists of one 4-amino-pyridinium cation and one hydrogen (9-phos-phono-non-yl)phospho-nate anion, both in general positions. As expected, the 4-amino-pyridinium moieties are protonated exclusively at their endocyclic nitro-gen atom due to a mesomeric stabilization by the imine form which would not be given in the corresponding double-protonated dicationic species. In the crystal, the phosphonyl (-PO3H2) and hydrogen phospho-nate (-PO3H) groups of the anions form two-dimensional O-H⋯O hydrogen-bonded networks in the ab plane built from 24-membered hydrogen-bonded ring motifs with the graph-set descriptor R66(24). These networks are pairwise linked by the anions' alkyl-ene chains. The 4-amino-pyridinium cations are stacked in parallel displaced face-to-face arrangements and connect neighboring anionic substructures via medium-strong charge-supported N-H⋯O hydrogen bonds along the c axis. The resulting three-dimensional hydrogen-bonded network shows clearly separated hydro-philic and hydro-phobic structural domains.

  10. Hydrogen bonding, π–π stacking and van der Waals forces-dominated layered regions in the crystal structure of 4-amino­pyridinium hydrogen (9-phosphono­non­yl)phospho­nate

    Science.gov (United States)

    van Megen, Martin; Reiss, Guido J.; Frank, Walter

    2016-01-01

    The asymmetric unit of the title mol­ecular salt, [C5H7N2 +][(HO)2OP(CH2)9PO2(OH)−], consists of one 4-amino­pyridinium cation and one hydrogen (9-phos­phono­non­yl)phospho­nate anion, both in general positions. As expected, the 4-amino­pyridinium moieties are protonated exclusively at their endocyclic nitro­gen atom due to a mesomeric stabilization by the imine form which would not be given in the corresponding double-protonated dicationic species. In the crystal, the phosphonyl (–PO3H2) and hydrogen phospho­nate (–PO3H) groups of the anions form two-dimensional O—H⋯O hydrogen-bonded networks in the ab plane built from 24-membered hydrogen-bonded ring motifs with the graph-set descriptor R 6 6(24). These networks are pairwise linked by the anions’ alkyl­ene chains. The 4-amino­pyridinium cations are stacked in parallel displaced face-to-face arrangements and connect neighboring anionic substructures via medium–strong charge-supported N—H⋯O hydrogen bonds along the c axis. The resulting three-dimensional hydrogen-bonded network shows clearly separated hydro­philic and hydro­phobic structural domains. PMID:27746940

  11. Characteristics of a Broadband Dye Laser Using Pyrromethene and Rhodamine Dyes

    Science.gov (United States)

    Tedder, Sarah A.; Danehy, Paul M.; Wheeler, Jeffrey L.

    2011-01-01

    A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full-width half-maximum (FWHM) from 592 to 610 nm was created for the use in a dual-pump broadband CARS system called WIDECARS. The desired broadband dye laser was generated with a mixture of Pyrromethene dyes as an oscillator gain medium and a spectral selective optic in the oscillator cavity. A mixture of Rhodamine dyes were used in the amplifier dye cell. To create this laser a study was performed to characterize the spectral behavior of broadband dye lasers created with Rhodamine dyes 590, 610, and 640, Pyrromethene dyes 597 and 650 as well as mixture of these dyes.

  12. Dyeing of Polyester Woven Fabric with Disperse Dye Using Conventional and Microwave Technique

    Directory of Open Access Journals (Sweden)

    Uzma Syed

    2014-07-01

    Full Text Available Polyester fabric is generally dyed using high temperature dyeing technique and carrier. Both techniques require high energy consumption while few carriers are toxic in nature. In this study, 100% polyester woven fabric was dyed by microwave and conventional dyeing technique with disperse dye; Foron Blue RD GLN by an exhaust method for short dyeing cycle (15 and 30 min. The fabric samples were dyed using conventional high temperature dyeing technique using recommended recipe. Moreover, samples were also dyed using microwave technique with recommended recipe and by the addition of salt and urea, pre-treatment with caustic and organic solvent for improving the dye uptake value and fastness properties. The dyeing assessment; (K/S?max value by Datacolor spectrophotometer, dye uniformity by optical microscope and washing fastness by grey scale were measured. It has been observed that over conventional dyeing method, microwave irradiation dyed sample gives almost 70% high (K/S?max value and uniform dye penetration and good to very good washing fastness property. In addition, microwave dyeing gives excellent dyeing behavior at short dyeing cycle; 15 min; hence saves energy and sustainable dyeing process

  13. APPLICATION OF NATURAL DYES ON TEXTILE: A REVIEW

    OpenAIRE

    Tassew Alemayehu, Zenebesh Teklemariam

    2017-01-01

    This paper reviews the characterization and chemical/biochemical analysis of natural dyes. Extraction of colorants from different natural sources, effects of different mordents and application of binary mixture of natural dyes. Natural dyes are different sources such as plant dyes animal dyes mineral dyes etc. and characteristics of natural dyes such as chemical/biochemical analysis by using UV-visible spectroscopic and chromatographic analysis.

  14. Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

    OpenAIRE

    Wei, Bo; Chen, Qiu-Yuan; Chen, Guoqiang; Tang, Ren-Cheng; Zhang, Jun

    2013-01-01

    There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes ...

  15. [Benzidine dyes and risk of bladder cancer].

    Science.gov (United States)

    Miyakawa, M; Yoshida, O

    1989-12-01

    Until the early 1970's there was little concern about dyes which contain benzidine as an integral part of their chemical structure. Furthermore, use of the finished dyes was not considered dangerous. To ascertain whether azo dyes are associated with risk of development of bladder tumors in workers who handpaint Yuzen-type silk kimonos in Kyoto, we investigated the disintegration of dyes to benzidine. In these studies, we found that in rats and mice benzidine-based dyes are metabolized to benzidine and that the azo linkage of benzidine dyes is reduced by Escherichia coli and soil bacteria. These experimental findings were reported previously. In this report, we outline an approach to these studies. Many of the dyes used to color paper, textiles, lipstick, bait used by fishermen, as well as hair dyes, and dyes used in research, for pharmaceutical products, and by defence personnel for the detection of liquid chemical warfare agents, have been shown to be potentially mutagenic or carcinogenic. We review the literature on these dyes.

  16. Bisquaternary pyridinium oximes: Comparison of in-vitro reactivation potency of compounds bearing aliphatic linkers and heteroaromatic linkers for paraoxon-inhibited electric eel and recombinant human acetylcholinesterase

    Science.gov (United States)

    Bharate, Sandip B.; Guo, Lilu; Reeves, Tony E.; Cerasoli, Douglas M.; Thompson, Charles M.

    2009-01-01

    Oxime reactivators are the drugs of choice for the post-treatment of OP (organophosphorus) intoxication and used widely for mechanistic and kinetic studies of OP-inhibited cholinesterases. The purpose of the present study was to evaluate new oxime compounds to reactivate acetylcholinesterase (AChE) inhibited by the OP paraoxon. Several new bisquaternary pyridinium oximes with heterocyclic linkers along with some known bisquaternary pyridinium oximes bearing aliphatic linkers were synthesized and evaluated for their in vitro reactivation potency against paraoxon-inhibited electric eel acetylcholinesterase (EeAChE) and recombinant human acetylcholinesterase (rHuAChE). Results herein indicate that most of the compounds are better reactivators of EeAChE than of rHuAChE. The reactivation potency of two different classes of compounds with varying linker chains was compared and observed that the structure of the connecting chain is an important factor for the activity of the reactivators. At a higher concentration (10−3 M), compounds bearing aliphatic linker showed better reactivation than compounds with heterocyclic linkers. Interestingly, oximes with a heterocyclic linker inhibited AChE at higher concentration (10−3 M), whereas their ability to reactivate was increased at lower concentrations (10−4 M and 10−5 M). Compounds bearing either a thiophene linker 26, 46 or a furan linker 31 showed 59%, 49% and 52% reactivation of EeAChE, respectively, at 10−5 M. These compounds showed 14%, 6% and 15% reactivation of rHuAChE at 10−4 M. Amongst newly synthesized analogs with heterocyclic linkers (26–35 and 45–46), compound 31, bearing furan linker chain, was found to be the most effective reactivator with a kr 0.042 min−1, which is better than obidoxime (3) for paraoxon-inhibited EeAChE. Compound 31 showed a kr 0.0041 min−1 that is near equal to pralidoxime (1) for paraoxon-inhibited rHuAChE. PMID:20005727

  17. Synthesis, characterization and dyeing behavior of heterocyclic acid dyes and mordent acid dyes on wool and silk fabrics

    Directory of Open Access Journals (Sweden)

    Patel Hitendra M.

    2012-01-01

    Full Text Available Novel heterocyclic acid and mordent acid dyes were synthesized by the coupling of diazonium salt solution of different aromatic amines with 2- butyl-3-(4-hydroxybenzoylbenzofuran. The resulting heterocyclic acid dyes were characterized by spectral techniques, i.e., elemental analysis, IR, 1HNMR, 13C-NMR spectral studies and UV- visible spectroscopy. The dyeing performance of all the heterocyclic acid dyes was evaluated on wool and silk fabrics. The dyeing of chrome pre treated wool and silk fabrics showed better hues on mordented fabrics. Dyeing of wool and silk fabrics resulted in pinkish blue to red shades with very good depth and levelness. The dyed fabrics showed excellent to very good light, washing, perspiration, sublimation and rubbing fastness.

  18. Effect of Solvent, Dye-Loading Time, and Dye Choice on the Performance of Dye-Sensitized Solar Cells

    National Research Council Canada - National Science Library

    Rajab, Fahd M

    2016-01-01

    .... The dyes are dissolved in different solvent mixtures, including supercritical carbon dioxide, as well as combinations of more traditional solvents including mixtures of acetonitrile, and t-butanol...

  19. Synthesis and characterization of reactive dye-cassava mesocarp ...

    African Journals Online (AJOL)

    USER

    2010-05-17

    May 17, 2010 ... properties and good dye fixation on the substrate are of importance in the preparation of stable and efficient dye modified cellulosic ion exchange resins. Key words: Reactive dye, dye modified cassava mesocarp, cation exchange resins. INTRODUCTION. Reactive dyes contain functional groups capable of.

  20. Environmentally Friendly Techniques for Wool Dyeing Process

    Directory of Open Access Journals (Sweden)

    Antighin Simona

    2015-11-01

    Full Text Available The aim of this research was to evaluate the influence of dyeing process on the quality of surface waters contaminated with heavy metals and organic compounds, resulted after the wool dyeing process. In order to mark out this aspects an environment friendly method was proposed which involves dyeing wool fiber with new complex combinations derived from a new acid dyes which were complexed, using copper, iron, nickel and zinc salts at 2:1 combination ratio. In order to point out the environmental point of view of wastewaters an experimental protocol was tested by dyeing wool fiber at different pH. Evaluation of complexed combinations impact on the environment involve the following indicators: consumption degree of dyeing solution from the process bath, treatment degree related to the organic content expressed by COD indicator and treatment degree related to the heavy metal concentration respectively.

  1. Azo dyes and human health: A review.

    Science.gov (United States)

    Chung, King-Thom

    2016-10-01

    Synthetic azo dyes are widely used in industries. Gerhardt Domagk discovered that the antimicrobial effect of red azo dye Prontosil was caused by the reductively cleaved (azo reduction) product sulfanilamide. The significance of azo reduction is thus revealed. Azo reduction can be accomplished by human intestinal microflora, skin microflora, environmental microorganisms, to a lesser extent by human liver azoreductase, and by nonbiological means. Some azo dyes can be carcinogenic without being cleaved into aromatic amines. However, the carcinogenicity of many azo dyes is due to their cleaved product such as benzidine. Benzidine induces various human and animal tumors. Another azo dye component, p-phenylenediamine, is a contact allergen. Many azo dyes and their reductively cleaved products as well as chemically related aromatic amines are reported to affect human health, causing allergies and other human maladies.

  2. Increased light harvesting in dye-sensitized solar cells with energy relay dyes

    KAUST Repository

    Hardin, Brian E.

    2009-06-21

    Conventional dye-sensitized solar cells have excellent charge collection efficiencies, high open-circuit voltages and good fill factors. However, dye-sensitized solar cells do not completely absorb all of the photons from the visible and near-infrared domain and consequently have lower short-circuit photocurrent densities than inorganic photovoltaic devices. Here, we present a new design where high-energy photons are absorbed by highly photoluminescent chromophores unattached to the titania and undergo Förster resonant energy transfer to the sensitizing dye. This novel architecture allows for broader spectral absorption, an increase in dye loading, and relaxes the design requirements for the sensitizing dye. We demonstrate a 26% increase in power conversion efficiency when using an energy relay dye (PTCDI) with an organic sensitizing dye (TT1). We estimate the average excitation transfer efficiency in this system to be at least 47%. This system offers a viable pathway to develop more efficient dye-sensitized solar cells.

  3. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye

    Science.gov (United States)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it.

  4. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye.

    Science.gov (United States)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-05

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. OPTIMIZATION OF PH AND CONCENTRATION OF DYE LIQUER OF NATURAL DYES

    OpenAIRE

    Shweta Singh* & Dr. Divya Rani Singh

    2017-01-01

    At present research is focused to find out alternative dyes for food and clothing and it should be eco friendly , readly available , cost effective and safe to use both in food material and fabrics. The usage of the plant based natural dyes is traced back to ancient civilization . Due to the environmental and health hazards problems caused by the synthetic dyes.Now people are more concerned about the usage of natural dyes during the last two decades. Botanistists have identified more than...

  6. Transformation of codeine and codeine-6-glucuronide to opioid analogues by urine adulteration with pyridinium chlorochromate: potential issue for urine drug testing.

    Science.gov (United States)

    Luong, Susan; Ung, Alison T; Kalman, John; Fu, Shanlin

    2014-07-30

    Pyridinium chlorochromate (PCC) is the active ingredient of 'Urine Luck', a commercially available in vitro adulterating agent used to conceal the presence of drugs in a urine specimen. The exposure of codeine and its major glucuronide metabolite codeine-6-glucuronide (C6G) to PCC was investigated to determine whether PCC is an effective masking agent for these opiate compounds. Following the addition of PCC to both spiked and authentic codeine and C6G-positive urine specimens, the samples were monitored using liquid chromatography/mass spectrometry (LC/MS). Stable reaction products were identified and characterized using high-resolution MS analysis and, where possible, nuclear magnetic resonance (NMR) analysis. It was determined that PCC effectively oxidizes codeine and C6G, thus altering the original codeine-to-C6G ratio in the urine specimen. Four reaction products were identified for codeine: codeinone, 14-hydroxycodeinone, 6-O-methylcodeine and 8-hydroxy-7,8-dihydrocodeinone. Similarly, three reaction products were identified for C6G: codeinone, codeine and a lactone of C6G (tentative assignment). Besides addressing the complications added to interpretation, more investigation is warranted to further determine their potential for use as markers for monitoring the presence of codeine and C6G in urine specimens adulterated with PCC. Copyright © 2014 John Wiley & Sons, Ltd.

  7. Photodynamic effect of meso-(aryl)porphyrins and meso-(1-methyl-4-pyridinium)porphyrins on HaCaT keratinocytes.

    Science.gov (United States)

    Slomp, Amanda M; Barreira, Sandra M W; Carrenho, Luise Z B; Vandresen, Camila C; Zattoni, Ingrid F; Ló, Stephanie M S; Dallagnol, Juliana C C; Ducatti, Diogo R B; Orsato, Alexandre; Duarte, M Eugênia R; Noseda, Miguel D; Otuki, Michel F; Gonçalves, Alan G

    2017-01-15

    Sixteen porphyrins, including neutral, anionic and cationic meso-(aryl)porphyrins and meso-(1-methyl-4-pyridinium)porphyrins were herein evaluated in terms of their photosensitizing properties against HaCaT keratinocytes. After an initial screening, the cationic porphyrins were studied in more details, by both determining their log POW and performing PDT assays in lower porphyrin concentrations. Porphyrins presenting two or more adjacent positively charged groups, directly linked to the macrocycle meso positions, appeared to be the most effective photosensitizers. The present study also included the dicationic 5,10-diphenyl-15,20-di(1-methylpyridinium-4-yl)porphyrin (14b), which has previously shown promising results on a psoriasis-like in vivo model. Overall results indicated that the beneficial effect related to porphyrins on psoriasis can be related to the decreasing of keratinocyte viability. Furthermore, some of the cationic porphyrins studied appeared as candidates to be utilized as photosensitizers for psoriasis treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Activity coefficients at infinite dilution measurements for organic solutes and water in the ionic liquid 1-(3-hydroxypropyl)pyridinium trifluorotris(perfluoroethyl)phosphate.

    Science.gov (United States)

    Marciniak, Andrzej; Wlazło, Michał

    2010-05-27

    The activity coefficients at infinite dilution, gamma(13)(infinity), for 37 solutes, alkanes, alkenes, alkynes, cycloalkanes, aromatic hydrocarbons, alcohols, thiophene, ethers, ketones, and water, in the ionic liquid 1-(3-hydroxypropyl)pyridinium trifluorotris(perfluoroethyl)phosphate [N-C(3)OHPY][FAP] were determined by gas-liquid chromatography at the temperatures from 308.15 to 358.15 K. The partial molar excess enthalpies at infinite dilution values DeltaH(1)(E,infinity) were calculated from the experimental gamma(13)(infinity) values obtained over the temperature range. The selectivities for aliphatics/aromatics hydrocarbons separation problem were calculated from the gamma(13)(infinity) values and compared to the literature values for other ionic liquids, N-methylpyrrolidone (NMP) and sulfolane. It was found that the investigated [N-C(3)OHPY][FAP] ionic liquid shows much higher selectivity and capacity at infinite dilution than the generally used organic solvents such as NMP, sulfolane, and other ionic liquids.

  9. Solvent-free fluidic organic dye lasers.

    Science.gov (United States)

    Choi, Eun Young; Mager, Loic; Cham, Tran Thi; Dorkenoo, Kokou D; Fort, Alain; Wu, Jeong Weon; Barsella, Alberto; Ribierre, Jean-Charles

    2013-05-06

    We report on the demonstration of liquid organic dye lasers based on 9-(2-ethylhexyl)carbazole (EHCz), so-called liquid carbazole, doped with green- and red-emitting laser dyes. Both waveguide and Fabry-Perot type microcavity fluidic organic dye lasers were prepared by capillary action under solvent-free conditions. Cascade Förster-type energy transfer processes from liquid carbazole to laser dyes were employed to achieve color-variable amplified spontaneous emission and lasing. Overall, this study provides the first step towards the development of solvent-free fluidic organic semiconducting lasers and demonstrates a new kind of optoelectronic applications for liquid organic semiconductors.

  10. Solubilization of Hydrophobic Dyes in Surfactant Solutions

    Directory of Open Access Journals (Sweden)

    Ali Reza Tehrani-Bagha

    2013-02-01

    Full Text Available In this paper, the use of surfactants for solubilization of hydrophobic organic dyes (mainly solvent and disperse dyes has been reviewed. The effect of parameters such as the chemical structures of the surfactant and the dye, addition of salt and of polyelectrolytes, pH, and temperature on dye solubilization has been discussed. Surfactant self-assemble into micelles in aqueous solution and below the concentration where this occurs—the critical micelle concentration (CMC—there is no solubilization. Above the CMC, the amount of solubilized dye increases linearly with the increase in surfactant concentration. It is demonstrated that different surfactants work best for different dyes. In general, nonionic surfactants have higher solubilization power than anionic and cationic surfactants. It is likely that the reason for the good performance of nonionic surfactants is that they allow dyes to be accommodated not only in the inner, hydrocarbon part of the micelle but also in the headgroup shell. It is demonstrated that the location of a dye in a surfactant micelle can be assessed from the absorption spectrum of the dye-containing micellar solution.

  11. Metal peroxide- polymer composites for dye degradation

    Science.gov (United States)

    Anshu, Ashwini; Vijayaraghavan, R.

    2017-11-01

    Semiconductor metal oxides/its composites with polymers have been explored for dye degradation through photocatalytic mechanism; these require UV or visible light for activation. Hence, there is need to develop (photo) catalyst that work in absence/presence of light. Towards this objective we are exploring metal peroxides and its composites for dye degradation. Here, we report our work on magnesium peroxide and its composites for dye degradation by photochemical pathways. The nanocomposites are synthesized from monomers and peroxides. The synthesized composites have been characterized by IR, DRS and powder XRD. The composites did not degrade dyes in dark.

  12. Tunable Optofluidic Third Order DFB Dye Laser

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2007-01-01

    We present a low-threshold polymer-based nanofluidic dye laser. By employing a third order DFB laser resonator, we demonstrate a threshold fluence of ~7 muJ/mm2 and a tunability of 45 nm using a single laser dye......We present a low-threshold polymer-based nanofluidic dye laser. By employing a third order DFB laser resonator, we demonstrate a threshold fluence of ~7 muJ/mm2 and a tunability of 45 nm using a single laser dye...

  13. Release Control of Dye from Agar Ball

    OpenAIRE

    板屋, 智之; 山村, 俊貴; 唐澤, 有太朗

    2013-01-01

    Agar is a special product of Nagano prefecture. To utilize agar gel as adsorbing or releasing material of dyes or drugs, spherical agar gel “agar ball” was prepared by dropping aqueous agar solution into salad oil. And releasing behavior of a dye (rhodamine B) from agar ball was studied. The dye is released easily from agar ball, but the release can be controlled by hybiridazation of agar and galatin. In addition, it was found that agar ball could extract the dye from oil phase containing the...

  14. Estimation of Fluorescent Dye Amount in Tracer Dye Test

    Science.gov (United States)

    Pekkan, Emrah; Balkan, Erman; Balkan, Emir

    2015-04-01

    Karstic groundwater is more influenced by human than the groundwater that disperse in pores. On the other hand karstic groundwater resources, in addition to providing agricultural needs, livestock breeding, drinking and domestic water in most of the months of the year, they also supply drinking water to the wild life at high altitudes. Therefore sustainability and hydrogeological investigation of karstic resources is critical. Tracing techniques are widely used in hydrologic and hydrogeologic studies to determine water storage, flow rate, direction and protection area of groundwater resources. Karanfil Mountain (2800 m), located in Adana, Turkey, is one of the karstic recharge areas of the natural springs spread around its periphery. During explorations of the caves of Karanfil mountain, a 600 m deep cave was found by the Turkish and Polish cavers. At the bottom of the cave there is an underground river with a flow rate of approximately 0.5 m3/s during August 2014. The main spring is located 8 km far from the cave's entrance and its mean flow rate changes between 3.4 m3/s and 0.21 m3/s in March and September respectively according to a flowrate observation station of Directorate of Water Works of Turkey. As such frequent storms, snowmelt and normal seasonal variations in rainfall have a significant and rapid effect on the volume of this main spring resource. The objective of our research is to determine and estimate dye amount before its application on the field inspired from the previously literature on the subject. This estimation is intended to provide a preliminary application of a tracer test of a karstic system. In this study dye injection, inlet point will be an underground river located inside the cave and the observation station will be the spring that is approximately 8 km far from the cave entrance. On the other hand there is 600 meter elevation difference between cave entrance and outlet spring. In this test Rodamin-WT will be used as tracer and the

  15. Dataset on analysis of dyeing property of natural dye from Thespesia populnea bark on different fabrics

    Directory of Open Access Journals (Sweden)

    Kuchekar Mohini

    2018-02-01

    Full Text Available The natural dyes separated from plants are of gaining interest as substitutes for synthetic dyes in food and cosmetics. Thespesia populnea (T. populnea is widely grown plant and used in the treatment of various diseases. This study was aimed to separate natural dye from T. populnea bark and analysis of its dyeing property on different fabrics. In this investigation pharmacognostic study was carried out. The pharmacognostic study includes morphological study, microscopical examination, proximate analysis along with the phytochemical study. The dyeing of different fabric was done with a natural dye extracted from T. populnea bark. The fabrics like cotton, butter crep, polymer, chiken, lone, ulene and tarakasa were dye with plant extract. The various evaluation parameters were studied. It includes effect of washing with water, effect of soap, effect of sunlight, effect of alum, effect of Cupric sulphate, microscopical study of fabrics and visual analysis of dyeing by common people were studied. In results, natural dye isolated from T. populnea bark could be used for dyeing fabrics with good fastness properties. The studies reveals that, the dyeing property of fabrics after washing with water and soap, exposed to sunlight does not get affected. It was observed that cotton and tarakasa stains better as compared with other fabrics. It was concluded that the ethanolic extract having good dyeing property.

  16. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes.

    Science.gov (United States)

    Abdou, E M; Hafez, H S; Bakir, E; Abdel-Mottaleb, M S A

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

    Science.gov (United States)

    Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

  18. Dye Sensitized Solar Cell, DSSC

    Directory of Open Access Journals (Sweden)

    Pongsatorn Amornpitoksuk

    2003-07-01

    Full Text Available A dye sensitized solar cell is a new type of solar cell. The operating system of this solar cell type is similar to plant’s photosynthesis process. The sensitizer is available for absorption light and transfer electrons to nanocrystalline metal oxide semiconductor. The ruthenium(II complexes with polypyridyl ligands are usually used as the sensitizers in solar cell. At the present time, the complex of [Ru(2,2',2'’-(COOH3- terpy(NCS3] is the most efficient sensitizer. The total photon to current conversion efficiency was approximately 10% at AM = 1.5.

  19. Incorporating Multiple Energy Relay Dyes in Liquid Dye-Sensitized Solar Cells

    KAUST Repository

    Yum, Jun-Ho

    2011-01-05

    Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse from 400-590 nm matching the optical window of the zinc phthalocyanine sensitizer was observed due to Förster resonance energy transfer (FRET) from the two energy relay dyes to the sensitizing dye. The complementary absorption spectra of the energy relay dyes and high excitation transfer efficiencies result in a 35% increase in photovoltaic performance. © 2011 Wiley-VCH Verlag GmbH& Co. KGaA.

  20. Metal oxide-encapsulated dye-sensitized photoanodes for dye-sensitized solar cells

    Science.gov (United States)

    Hupp, Joseph T.; Son, Ho-Jin

    2016-01-12

    Dye-sensitized semiconducting metal oxide films for photoanodes, photoanodes incorporating the films and DSCs incorporating the photoanodes are provided. Also provided are methods for making the dye sensitized semiconducting metal oxide films. The methods of making the films are based on the deposition of an encapsulating layer of a semiconducting metal oxide around the molecular anchoring groups of photosensitizing dye molecules adsorbed to a porous film of the semiconducting metal oxide. The encapsulating layer of semiconducting metal oxide is formed in such a way that it is not coated over the chromophores of the adsorbed dye molecules and, therefore, allows the dye molecules to remain electrochemically addressable.

  1. Simultaneous dyeing and antibacterial finishing for cotton cellulose using a new reactive dye.

    Science.gov (United States)

    Farouk, R; Gaffer, H E

    2013-08-14

    Simultaneous dyeing and antibacterial finishing for cotton fabric using a new antibacterial reactive dye having a modified chemical structure to the commercial reactive dye CI Reactive Red 198 were studied. This modification was carried out by replacing metanilic acid in the commercial dye with 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (sulfadimidine). Optimum exhaustion and fixation values were achieved at 60 g/l sodium sulphate and 20 g/l sodium carbonate for both dyes. The modified dye exhibited higher substantivity, exhaustion and fixation efficiency compared to the commercial dye. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria. The cotton dyed with the modified dye shows higher antibacterial efficacy compared to the dyed cotton fabric using the commercial dye, especially on gram negative (E. coli) bacteria. All the reactive dyeings also exhibited high fastness properties. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Eco-Friendly Dyeing of Cotton with Indigo Dye By Electrochemical Method

    Science.gov (United States)

    Prabu, H. Gurumallesh; Sarala, K.; Babu, S. Ananda; Savitha, K. U.

    2011-07-01

    Eco-friendly dyeing of cotton was performed in two step process; (i) enzymatic pre-treatment of grey cotton fabric and (ii) Electrochemical dyeing of the pre-treated cotton fabric with indigo. The enzymatic pre-treatment was done in three methods; (i) amylase treatment only, (ii) amylase and hydrogen peroxide treatment and (iii) single bath method. The dyeing was carried out with the pre-treated cotton fabric. The reduction of indigo dye by electrochemical method was initiated by applying potential. Then the dyeing was carried out different concentrations of dye, glucose and NaOH. Conventional method of dyeing was also carried out and compared with the electrochemical method. Dyeability was measured by computer colour matching (CCM) GretagMacbeth colour eye 2180UV instrument.

  3. High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells

    KAUST Repository

    Hardin, Brian E.

    2010-08-11

    The energy relay dye, 4-(Dicyanomethylene)-2-methyl-6-(4- dimethylaminostyryl)-4H-pyran (DCM), was used with a near-infrared sensitizing dye, TT1, to increase the overall power conversion efficiency of a dye-sensitized solar cell (DSC) from 3.5% to 4.5%. The unattached DCM dyes exhibit an average excitation transfer efficiency (EÌ?TE) of 96% inside TT1-covered, mesostructured TiO2 films. Further performance increases were limited by the solubility of DCM in an acetonitrile based electrolyte. This demonstration shows that energy relay dyes can be efficiently implemented in optimized dye-sensitized solar cells, but also highlights the need to design highly soluble energy relay dyes with high molar extinction coefficients. © 2010 American Chemical Society.

  4. High order Bragg grating microfluidic dye laser

    DEFF Research Database (Denmark)

    Balslev, Søren; Kristensen, Anders

    2004-01-01

    We demonstrate a single mode distributed feedback liquid dye laser, based on a short 133 'rd order Bragg grating defined in a single polymer layer between two glass substrates.......We demonstrate a single mode distributed feedback liquid dye laser, based on a short 133 'rd order Bragg grating defined in a single polymer layer between two glass substrates....

  5. Optofluidic third order distributed feedback dye laser

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2006-01-01

    This letter describes the design and operation of a polymer-based third order distributed feedback (DFB) microfluidic dye laser. The device relies on light confinement in a nanostructured polymer film where an array of nanofluidic channels is filled by capillary action with a liquid dye solution...

  6. Predicting Solar-Cell Dyes for Cosensitization

    Energy Technology Data Exchange (ETDEWEB)

    Bayliss, Sam L. [Cavendish; Cole, Jacqueline M. [Cavendish; Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, United States; Institute; Waddell, Paul G. [Cavendish; Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234, Australia; McKechnie, Scott [Cavendish; Liu, Xiaogang [Cavendish

    2014-06-19

    A major limitation of using organic dyes for dye-sensitized solar cells (DSCs) has been their lack of broad optical absorption. Co-sensitization, in which two complementary dyes are incorporated into a DSC, offers a route to combat this problem. Here we construct and implement a design route for materials discovery of new dyes for co-sensitization, beginning with a chemically compatible series of existing laser dyes which are without an anchor group necessary for DSC use. We determine the crystal structures for this dye series, and use their geometries to establish the DSC molecular design prerequisites aided by density-functional theory and time-dependent density-functional theory calculations. Based on insights gained from these existing dyes, modified sensitizers are computationally designed to include a suitable anchor group. A DSC co-sensitization strategy for these modified sensitizers is predicted, using the central features of highest-occupied, and lowest-unoccupied molecular orbital positioning, optical absorption properties, intramolecular charge-transfer characteristics, and steric effects as selection criteria. Through this molecular engineering of a series of existing non-DSC dyes, we predict new materials for DSC co-sensitization.

  7. EFFECTS OF MORDANTING METHODS OF DYE FROM ...

    African Journals Online (AJOL)

    The effects analyzed are color fastness to; light, washing, wet and dry rubbing and color characteristics on CIELab color coordinates. The aqueous extraction method was used to extract the dye. Some selected mordants were used for dyeing viz; alum, potassium dichromate, ferrous sulphate, iron water and ash water.

  8. Dye Sensitizers for Photodynamic Therapy

    Directory of Open Access Journals (Sweden)

    Harold S. Freeman

    2013-03-01

    Full Text Available Photofrin® was first approved in the 1990s as a sensitizer for use in treating cancer via photodynamic therapy (PDT. Since then a wide variety of dye sensitizers have been developed and a few have been approved for PDT treatment of skin and organ cancers and skin diseases such as acne vulgaris. Porphyrinoid derivatives and precursors have been the most successful in producing requisite singlet oxygen, with Photofrin® still remaining the most efficient sensitizer (quantum yield = 0.89 and having broad food and drug administration (FDA approval for treatment of multiple cancer types. Other porphyrinoid compounds that have received approval from US FDA and regulatory authorities in other countries include benzoporphyrin derivative monoacid ring A (BPD-MA, meta-tetra(hydroxyphenylchlorin (m-THPC, N-aspartyl chlorin e6 (NPe6, and precursors to endogenous protoporphyrin IX (PpIX: 1,5-aminolevulinic acid (ALA, methyl aminolevulinate (MAL, hexaminolevulinate (HAL. Although no non-porphyrin sensitizer has been approved for PDT applications, a small number of anthraquinone, phenothiazine, xanthene, cyanine, and curcuminoid sensitizers are under consideration and some are being evaluated in clinical trials. This review focuses on the nature of PDT, dye sensitizers that have been approved for use in PDT, and compounds that have entered or completed clinical trials as PDT sensitizers.

  9. Molecular engineering of simple phenothiazine-based dyes to modulate dye aggregation, charge recombination, and dye regeneration in highly efficient dye-sensitized solar cells.

    Science.gov (United States)

    Hua, Yong; Chang, Shuai; He, Jian; Zhang, Caishun; Zhao, Jianzhang; Chen, Tao; Wong, Wai-Yeung; Wong, Wai-Kwok; Zhu, Xunjin

    2014-05-19

    A series of simple phenothiazine-based dyes, namely, TP, EP, TTP, ETP, and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye-sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (Jsc = 15.2 mA cm(-2), Voc =0.783 V, fill factor (FF) = 0.679) and 7.87 % (Jsc = 16.1 mA cm(-2), Voc = 0.717 V, FF = 0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I(-)/I3(-) redox couple. By replacing the T group with the E unit, EP-based DSSCs had a slightly lower PCE of 7.98 % with a higher short-circuit photocurrent (Jsc) of 16.7 mA cm(-2). The dye ETP, with a mixture of E and T, had an even lower PCE of 5.62 %. Specifically, the cell based on the dye EEP, with a dimer of E, had inferior Jsc and Voc values and corresponded to the lowest PCE of 2.24 %. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Reduction of colorants in nylon flock dyeing effluent

    Science.gov (United States)

    Fan, Qinguo; Hoskote, Sunil; Hou, Yuejun

    2001-02-01

    The batch dyeing of fiber materials such as staple fibers and flock is usually carried out by exhaustion methods. However, the dyeing of flock fibers, either nylon, PET or acetate, with acid or disperse dyes is not 100 percent efficient in terms of dye utilization. Optimally, only about 80 to 85% of the dyes used for dark shade in a dye bath can be exhausted onto the target fibers. Therefore, the remaining dyes in the spent dye bath are generally not reused and are usually discharged with minimum treatment, together with the dyeing chemicals into the sewage wastewater system causing environmental pollution. We are presenting technical solutions to reduce the colorants and chemical auxiliaries in the fiber dyeing effluents by: (1) optimizing the acid dyeing conditions such as salt addition and pH control; (2) reuse of the spent dye bath that remain after the original dyeing process. In the lab scale trials, we have successfully raised the acid dye exhaustion to over 90% by optimizing the dyeing conditions. The reuse of the spent acid dye bath also showed promising results with dye exhaustion ranging from 91 to 93% after 4 times reuse.

  11. Synthesis and biological properties of some 3-[(N-substituted-amino)pyridinium-4-thiomethyl]-7-[2-(2-amino-thiazol- 4-yl)-2-(Z)-(methoxyimino)acetamido]ceph-3-em-4-carboxylates.

    Science.gov (United States)

    Branch, C L; Adams, R G; Brain, E G; Guest, A W; Harrington, F P; Knott, S J; Pearson, M J; Zomaya, I I

    1993-08-01

    The synthesis and antibacterial activity of a series of beta-lactamase stable, broad spectrum 7-[2-(2-amino-thiazol-4-yl)-2-(Z)-(methoxyimino)acetamido]-cephalo sporins, characterised by a C-3-[N-(substituted-amino)pyridinium-4-thiomethyl] group, is described. Gram-positive and Gram-negative bacteria including extended spectrum beta-lactamase-producing strains were most susceptible to the N-amino- and N-methylamino derivatives (3a) and (3b); with the exception of Pseudomonas aeruginosa, (3b) was more active in vitro and in vivo than cefpirome or ceftazidime.

  12. Activity coefficients at infinite dilution and physicochemical properties for organic solutes and water in the ionic liquid 1-(3-hydroxypropyl)pyridinium bis(trifluoromethylsulfonyl)-amide

    Energy Technology Data Exchange (ETDEWEB)

    Marciniak, Andrzej, E-mail: a.marciniak@ch.pw.edu.pl [Department of Physical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland)

    2011-10-15

    Highlights: > The {gamma}{sub 13}{sup {infinity}} and KL for 46 solutes in the ionic liquid [N-C3OHPY][NTf2] were determined by GLC at different temperatures. > The partial molar excess Gibbs energies {Delta}G{sub 1}{sup E,{infinity}}, enthalpies {Delta}H{sub 1}{sup E,{infinity}} and entropies {Delta}S{sub 1}{sup E,{infinity}} at infinite dilution were calculated. > The selectivities for aliphatics/aromatics hydrocarbons separation problem were calculated and compared to other ILs, NMP and sulfolane. > The selectivities for selected compounds which form azeotropic mixtures were calculated. - Abstract: The activity coefficients at infinite dilution, {gamma}{sub 13}{sup {infinity}} and gas-liquid partition coefficients, K{sub L} for 46 solutes: alkanes, alkenes, alkynes, cycloalkanes, aromatic hydrocarbons, alcohols, thiophene, ethers, ketones, acetic acid, and water in the ionic liquid 1-(3-hydroxypropyl)pyridinium bis(trifluoromethylsulfonyl)-amide were determined by gas-liquid chromatography at the temperatures from (308.15 to 378.15) K. The partial molar excess Gibbs free energies {Delta}G{sub 1}{sup E,{infinity}}, enthalpies {Delta}H{sub 1}{sup E,{infinity}} and entropies {Delta}S{sub 1}{sup E,{infinity}} at infinite dilution were calculated from the experimental {gamma}{sub 13}{sup {infinity}} values obtained over the temperature range. The selectivities for aliphatic/aromatic hydrocarbons separation problem were calculated from the {gamma}{sub 13}{sup {infinity}} and compared to the literature values for other ionic liquids based on bis(trifluoromethylsulfonyl)-amide anion, NMP and sulfolane. It was found that the investigated ionic liquid shows much higher selectivity at infinite dilution than the general used organic solvents such as NMP, sulfolane and other ionic liquids. Additionally the selectivities for selected compounds which form azeotropic mixtures were calculated.

  13. Performance improvement of dye-sensitized solar cells (DSSC) by using dyes mixture from chlorophyll and anthocyanin

    Science.gov (United States)

    Pratiwi, D. D.; Nurosyid, F.; Kusumandari; Supriyanto, A.; Suryana, R.

    2017-11-01

    This article showed the effect of single and mixture natural dyes on the DSSC performance. The single dyes extracted from moss chlorophyll and mangosteen peels anthocyanin. The dyes mixture was prepared by mixing from both chlorophyll and anthocyanin. The absorbance of dyes solution and the adsorption of the dye onto the working electrode were analyzed using UV-Vis spectroscopy. The photocurrent-photovoltage of DSSCs were measured using I-V meter. The dyes mixture has an increased absorption at visible spectrum range as compared to single dye. The adsorption of the dyes mixture onto the TiO2 electrode has higher absorbance than single dye. The DSSC with single dye from moss chlorophyll and mangosteen peels anthocyanin resulted the conversion efficiency of 0.049% and 0.042% respectively. The dyes mixture of chlorophyll and anthocyanin improved the conversion efficiency of 0.154%.

  14. Adsorption of Dyes Using Different Types of Sand: A Review

    African Journals Online (AJOL)

    NICO

    KEYWORDS. Adsorption, dyes, low-cost adsorbents, sand. 1. Introduction. Several dyes and their break-down products are toxic for living organisms because dyes are not easily degradable and are gener- ally not removed from wastewater by conventional wastewater treatment systems; this makes it difficult to remove dyes ...

  15. Traditional Cloth Dyeing Enterprise at Ntonso: Challenges and ...

    African Journals Online (AJOL)

    There is a growing awareness to the threats posed by synthetic dyes. Natural plant-based dyes have proved to be important alternatives to synthetic dyes in the textile industry. The study investigated the traditional cottage textile dyeing enterprise at Ntonso, in the Ashanti Region of Ghana, to identify challenges facing the ...

  16. Removal of hazardous dye Ponceau-S by using Chitin:

    African Journals Online (AJOL)

    Sr030111Bin Comp

    Dye pollutants from textile dye industries are an important source of environment contamination. The dyes currently used in textile industry is about 10,000 (Poon et al., 1999) .It is estimated that 1-155 of the dyes are .... 100 ml red solution of Ponceau-S .The mixture was stirred on magnetic stirrer for different interval of time.

  17. Bleaching and diffusion dynamics in optofluidic dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Balslev, Søren; Mortensen, Asger

    2007-01-01

    The authors have investigated the bleaching dynamics that occur in optofluidic dye lasers where the liquid laser dye in a microfluidic channel is locally bleached due to optical pumping. They find that for microfluidic devices, the dye bleaching may be compensated through diffusion of dye molecules...... pumping devices. ©2007 American Institute of Physics....

  18. Comparative properties of pure and sulphonated dyes extracted ...

    African Journals Online (AJOL)

    Both the extracted and sulphonated dyes were applied on chrome-tanned leather using 2% and liquor-togood ratio of 50:1 dyeing conditions and the dyeing properties (exhaustion, fixation, glazing, levelness, migration and penetration) assessed. The light, wash and rub fastness properties of the dyeings were investigated.

  19. Standardization in biological staining. The influence of dye manufacturing

    DEFF Research Database (Denmark)

    Lyon, H

    2000-01-01

    for biological staining, standardization of all procedures and reagents is mandatory. In this paper, I focus particularly on dyes and consider the possibilities for obtaining standardized dyes. In general practice, most biological staining takes place with available commercial dyes. These dyes may or may...

  20. Synthesis and characterization of reactive dye-cassava mesocarp ...

    African Journals Online (AJOL)

    Results obtained show that the dyes have excellent dyeing properties attributable to chemical bond formation between the dye molecules and the hydroxyl groups of the substrate (cassava mesocarp). The satisfactory fastness properties and good dye fixation on the substrate are of importance in the preparation of stable ...

  1. Contact allergy to common ingredients in hair dyes

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rustemeyer, Thomas; Gonçalo, Margarida

    2013-01-01

    p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed.......p-Phenylenediamine (PPD) is the primary patch test screening agent for hair dye contact allergy, and approximately 100 different hair dye chemicals are allowed....

  2. Supramolecular hair dyes: a new application of cocrystallization

    DEFF Research Database (Denmark)

    Delori, Amit; Urquhart, Andrew; Oswald, Iain D. H.

    2016-01-01

    The manuscript presents the first report of hair dyes of various colors formed by cocrystallization. Unlike the most popular oxidative hair dye (OHD) products, these dyes are NH3 free and do not require H2O2 as a color developer. The importance of these new hair dyes products is further enhanced...

  3. Hypersensitivity to contrast media and dyes.

    Science.gov (United States)

    Brockow, Knut; Sánchez-Borges, Mario

    2014-08-01

    This article updates current knowledge on hypersensitivity reactions to diagnostic contrast media and dyes. After application of a single iodinated radiocontrast medium (RCM), gadolinium-based contrast medium, fluorescein, or a blue dye, a hypersensitivity reaction is not a common finding; however, because of the high and still increasing frequency of those procedures, patients who have experienced severe reactions are nevertheless frequently encountered in allergy departments. Evidence on allergologic testing and management is best for iodinated RCM, limited for blue dyes, and insufficient for fluorescein. Skin tests can be helpful in the diagnosis of patients with hypersensitivity reactions to these compounds. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Dye ingredients and energy conversion efficiency at natural dye sensitized solar cells

    Science.gov (United States)

    Özbay Karakuş, Mücella; Koca, İrfan; Er, Orhan; Çetin, Hidayet

    2017-04-01

    In this work, natural dyes extracted from the same genus but different species flowers were used as sensitizer in Dye Sensitized Solar Cell (DSSC). To clearly show dye ingredients effect on electrical characteristics, the same genus flowers were selected. The dye ingredients were analyzed by Gas Chromatography Mass Spectrometer (GC-MS). The dyes were modified by a procedure that includes refluxing in acetone. All results indicate a relationship between gallic acid quantity in dyes and solar cell efficiency. To gain further insight, the solar cell parameters were obtained by using the single-diode and double-diode models and they were compared to each other. It was observed that the applied process causes a decrease in series resistance. How the modification process and gallic acid affect energy conversion efficiency were argued in detail in the frame of results that were obtained from solar cell models.

  5. USE OF A NATURAL DYE FROM SERRATIA MARCESCENS SUBSPECIES MARCESCENS IN DYEING OF TEXTILE FABRICS

    OpenAIRE

    Ravindra Adivarekar; Jyoti Vaidyanathan; Madhura Nerurkar

    2013-01-01

    A strain of Serratia marcescens subspecies marcescens capable of producing a novel rose red pigment with a mass of 112 Da has been isolated from Mahim Mangroove soil. Studies regarding the growth conditions of bacteria, partial characterization of the produced pigment and use of this rose red pigment to dye natural fabrics has been studied and described. Dyeing of wool, cotton and silk fabrics with this rose red microbial pigment as natural dye indicated that the colour strength values and t...

  6. Effect of Solvent, Dye-Loading Time, and Dye Choice on the Performance of Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Fahd M. Rajab

    2016-01-01

    Full Text Available Anatase titania films with a thickness of up to 20 μm and deposited over a fluorine-doped tin-oxide substrate are impregnated with ruthenium dyes N-719 and N-749 using Dip and supercritical-fluid methods for the purpose of fabricating dye-sensitized solar cell devices. The dyes are dissolved in different solvent mixtures, including supercritical carbon dioxide, as well as combinations of more traditional solvents including mixtures of acetonitrile, and t-butanol. Analytical studies included thin-film analyzing and scanning electron microscopy to measure titania film thickness and porosity, UV-Vis spectroscopy to quantify dye concentration, and current-voltage device characterizations to assess energy conversion efficiency, as well as open-circuit voltage decay measurements and quantum efficiency to examine electron collection efficiency. A significant result is that using the dye N-749 in a solvent that includes supercritical carbon dioxide leads to energy conversion efficiencies that are higher for devices with a thick 20 μm semiconductor film than for the case of devices with thinner films, including the 10 μm film thickness that is traditionally considered an upper threshold. The supercritical-fluid method for the N-719 dye also enabled shorter impregnation duration than more conventional classical Dip Methods.

  7. Data mining with molecular design rules identifies new class of dyes for dye-sensitised solar cells

    NARCIS (Netherlands)

    Cole, Jacqueline M.; Low, Kian Sing; Ozoe, Hiroaki; Stathi, Panagiota; Kitamura, Chitoshi; Kurata, Hiroyuki; Rudolf, Petra; Kawase, Takeshi

    2014-01-01

    A major deficit in suitable dyes is stifling progress in the dye-sensitised solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over

  8. Whispering-gallery-mode dye lasers in blue, green, and orange regions using dye-doped, solid, small spheres

    OpenAIRE

    Taniguchi, Hiroshi; Fujiwara, Tamiya; Yamada, Hiroshi; Tanosaki, Shinji; Baba, Mamoru

    1993-01-01

    A whispering-gallery-mode (WGM) dye laser in blue, green, and orange regions is reported using dye-doped, solid, small spheres. A WGM dye laser is pumped by a transversely excited atmospheric UV N2 laser. Some features of the WGM dye laser are demonstrated.

  9. Ionic liquid-based dispersive liquid-liquid microextraction combined with functionalized magnetic nanoparticle solid-phase extraction for determination of industrial dyes in water.

    Science.gov (United States)

    Liang, Ning; Hou, Xiaohong; Huang, Peiting; Jiang, Chao; Chen, Lijuan; Zhao, Longshan

    2017-10-23

    N-butyl pyridinium bis((trifluoromethyl)sulfonyl)imide ([Hpy]NTf2) functionalized core/shell magnetic nanoparticles (MNPs, Fe3O4@SiO2@[Hpy]NTf2)) were prepared and applied as an adsorbent for magnetic solid phase extraction (MSPE) of three commonly used industrial dyes including malachite green, crystal violet and methylene blue. Extraction solution was mixed with 100 mg extraction material of Fe3O4@SiO2@[Hpy]NTf2, and 1 mL of acetonitrile was used to elute target analytes for further extraction and purification. [Hpy]NTf2 was used as extraction solution, and 500 μL methanol was selected as dispersive solvent in ionic liquid (IL) dispersive liquid-liquid microextraction (DLLME) method. After sonication for 5 min and centrifugation at 447 g for 10 min, 20 μL of sedimented phase was injected into HPLC-UV system. The limit of detection (LOD) and limit of quantification (LOQ) of current method were 0.03 and 0.16 μg·L(-1), respectively, which indicated the sensitivity was comparable or even superior to other reported methods. The relative recoveries of the target analytes ranged from 86.1% to 100.3% with relative standard deviations between 0.3% and 4.5%. The developed method has been successfully applied to determine the level of three industrial dyes in different water samples.

  10. Bioremediation of dyes by fungi isolated from contaminated dye effluent sites for bio-usability

    Science.gov (United States)

    Rani, Babita; Kumar, Vivek; Singh, Jagvijay; Bisht, Sandeep; Teotia, Priyanku; Sharma, Shivesh; Kela, Ritu

    2014-01-01

    Biodegradation and detoxification of dyes, Malachite green, Nigrosin and Basic fuchsin have been carried out using two fungal isolates Aspergillus niger, and Phanerochaete chrysosporium, isolated from dye effluent soil. Three methods were selected for biodegradation, viz. agar overlay and liquid media methods; stationary and shaking conditions at 25 °C. Aspergillus niger recorded maximum decolorization of the dye Basic fuchsin (81.85%) followed by Nigrosin (77.47%), Malachite green (72.77%) and dye mixture (33.08%) under shaking condition. Whereas, P. chrysosporium recorded decolorization to the maximum with the Nigrosin (90.15%) followed by Basic fuchsin (89.8%), Malachite green (83.25%) and mixture (78.4%). The selected fungal strains performed better under shaking conditions compared to stationary method; moreover the inoculation of fungus also brought the pH of the dye solutions to neutral from acidic. Seed germination bioassay study exhibited that when inoculated dye solutions were used, seed showed germination while uninoculated dyes inhibited germination even after four days of observation. Similarly, microbial growth was also inhibited by uninoculated dyes. The excellent performance of A. niger and P. chrysporium in the biodegradation of textile dyes of different chemical structures suggests and reinforces the potential of these fungi for environmental decontamination. PMID:25477943

  11. Transforming Benzophenoxazine Laser Dyes into Chromophores for Dye-Sensitized Solar Cells: A Molecular Engineering Approach

    Energy Technology Data Exchange (ETDEWEB)

    Schröder, Florian A. Y. N. [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK; Cole, Jacqueline M. [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK; Argonne National Laboratory, 9700 S. Cass Avenue Argonne IL 60439 USA; International Institute for Complex Adaptive Matter, University of California Davis, Davis CA 95616 USA; Waddell, Paul G. [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK; Australian Nuclear Science and Technology Organization, Lucas Heights, New South Wales 2234 Australia; McKechnie, Scott [Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue Cambridge CB3 0HE UK

    2015-02-03

    The re-functionalization of a series of four well-known industrial laser dyes, based on benzophenoxazine, is explored with the prospect of molecularly engineering new chromophores for dye-sensitized solar cell (DSC) applications. Such engineering is important since a lack of suitable dyes is stifling the progress of DSC technology. The conceptual idea involves making laser dyes DSC-active by chemical modification, while maintaining their key property attributes that are attractive to DSC applications. This molecular engineering follows a step-wise approach. Firstly, molecular structures and optical absorption properties are determined for the parent laser dyes: Cresyl Violet (1); Oxazine 170 (2); Nile Blue A (3), Oxazine 750 (4). These reveal structure-property relationships which define the prerequisites for computational molecular design of DSC dyes; the nature of their molecular architecture (D-π-A) and intramolecular charge transfer. Secondly, new DSC dyes are computationally designed by the in silico addition of a carboxylic acid anchor at various chemical substitution points in the parent laser dyes. A comparison of the resulting frontier molecular orbital energy levels with the conduction band edge of a TiO2 DSC photoanode and the redox potential of two electrolyte options I-/I3- and Co(II/III)tris(bipyridyl) suggests promise for these computationally designed dyes as co-sensitizers for DSC applications.

  12. DFT Studies on the electronic structures of indoline dyes for dye-sensitized solar cells

    Directory of Open Access Journals (Sweden)

    JIE XU

    2010-02-01

    Full Text Available A series of indoline dyes with promising efficiency for dye-sensitized solar cells (DSSCs were studied using the density functional theory at the B3LYP/6-31g (d level. The ground-state geometries, electronic structures and absorption spectra of these dyes are reported. The calculated results indicate that the energy levels of the HOMOs and LUMOs of these dyes are advantageous for electron injection. Their intense and broad absorption bands as well as favorable excited-state energy levels are key factor for their outstanding efficiencies in DSSCs.

  13. (E-1-Methyl-4-[2-(2-naphthylvinyl]pyridinium iodideThis paper is dedicated to the late Her Royal Highness Princess Galyani Vadhana Krom Luang Naradhiwas Rajanagarindra for her patronage of Science in Thailand.

    Directory of Open Access Journals (Sweden)

    Hoong Kun Fun

    2009-06-01

    Full Text Available In the title compound, C18H16N+·I−, the cation is disordered over two orientations related by a 180° rotation about its long axis with occupancies of 0.554 (7 and 0.446 (7. Both disorder components exist in an E configuration. The dihedral angle between the pyridinium ring and the naphthalene ring system is 4.7 (6° in the major disorder component and 1.6 (8° in the minor component. In the crystal structure, centrosymmetrically related cations are stacked along the a axis, with significant π–π interactions between the pyridinium ring and the naphthalene ring system [centroid-centroid distance = 3.442 (9 Å]. The iodide ions are located between adjacent columns of cations. The cations are linked to the iodide ions by C—H...I interactions. Weak C—H...π interactions involving the methyl group are also observed.

  14. Chromosome characterization using single fluorescent dye

    Energy Technology Data Exchange (ETDEWEB)

    Crissman, Harry A. (Los Alamos, NM); Hirons, Gregory T. (Irvine, CA)

    1995-01-01

    Chromosomes are characterized by fluorescent emissions from a single fluorescent dye that is excited over two different wavelengths. A mixture containing chromosomes is stained with a single dye selected from the group consisting of TOTO and YOYO and the stained chromosomes are placed in a flow cytometer. The fluorescent dye is excited sequentially by a first light having a wavelength in the ultraviolet range to excite the TOTO or YOYO to fluoresce at a first intensity and by a second light having a wavelength effective to excite the TOTO or YOYO dye to fluoresce at a second intensity. Specific chromosomes may be identified and sorted by intensity relationships between the first and second fluorescence emissions.

  15. Visible Light Dye-Sensitized Photosensititve Systems

    National Research Council Canada - National Science Library

    Fang Gao; Yong-yuan Yang

    2000-01-01

      The visible light dyes were employed to sensitized o-Cl-Hexaarylbiimidazole (o-Cl-HABI). The obtained results suggested that o-Cl-HABI displayed a efficient sensitized photocleavage when exposed to Xenon lamp...

  16. and dyes metabolized to benzidine were

    African Journals Online (AJOL)

    LAB

    2012-07-17

    Jul 17, 2012 ... Immobilized bitter gourd peroxidase was used for the successful and effective removal of water ..... the compounds that speed up the reaction rate by .... dyes mediated by partially purified turnip (Brassica rapa) peroxidase.

  17. Modeling the efficiency of Förster resonant energy transfer from energy relay dyes in dye-sensitized solar cells

    KAUST Repository

    Hoke, Eric T.

    2010-02-11

    Förster resonant energy transfer can improve the spectral breadth, absorption and energy conversion efficiency of dye sensitized solar cells. In this design, unattached relay dyes absorb the high energy photons and transfer the excitation to sensitizing dye molecules by Förster resonant energy transfer. We use an analytic theory to calculate the excitation transfer efficiency from the relay dye to the sensitizing dye accounting for dynamic quenching and relay dye diffusion. We present calculations for pores of cylindrical and spherical geometry and examine the effects of the Förster radius, the pore size, sensitizing dye surface concentration, collisional quenching rate, and relay dye lifetime. We find that the excitation transfer efficiency can easily exceed 90% for appropriately chosen dyes and propose two different strategies for selecting dyes to achieve record power conversion efficiencies. © 2010 Optical Society of America.

  18. Pre dye treated titanium dioxide nanoparticles synthesized by modified sol-gel method for efficient dye-sensitized solar cells

    Science.gov (United States)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2015-06-01

    Pure and pre dye treated titanium dioxide nanoparticles were prepared by sol-gel and modified sol-gel methods, respectively. The pre dye treatment has improved the properties of TiO2, such as uniform dye adsorption, reduced agglomeration, improved morphology and less dye aggregation. The brazilein pigment-rich Caesalpinia sappan heartwood extract was used as natural dye sensitizer for pure and pre dye treated TiO2 nanoparticles. Low cost and environment friendly dye-sensitized solar cells (DSSC) fabricated using pure and pre dye treated TiO2 nanoparticles sensitized by natural dye showed solar light to electron conversion efficiencies of 1.09 and 1.65 %, respectively. The pre dye treated TiO2-based DSSC showed 51 % improvement in efficiency when compared to that of conventionally prepared DSSC.

  19. Improved Charge-Transfer Fluorescent Dyes

    Science.gov (United States)

    Meador, Michael

    2005-01-01

    Improved charge-transfer fluorescent dyes have been developed for use as molecular probes. These dyes are based on benzofuran nuclei with attached phenyl groups substituted with, variously, electron donors, electron acceptors, or combinations of donors and acceptors. Optionally, these dyes could be incorporated as parts of polymer backbones or as pendant groups or attached to certain surfaces via self-assembly-based methods. These dyes exhibit high fluorescence quantum yields -- ranging from 0.2 to 0.98, depending upon solvents and chemical structures. The wavelengths, quantum yields, intensities, and lifetimes of the fluorescence emitted by these dyes vary with (and, hence, can be used as indicators of) the polarities of solvents in which they are dissolved: In solvents of increasing polarity, fluorescence spectra shift to longer wavelengths, fluorescence quantum yields decrease, and fluorescence lifetimes increase. The wavelengths, quantum yields, intensities, and lifetimes are also expected to be sensitive to viscosities and/or glass-transition temperatures. Some chemical species -- especially amines, amino acids, and metal ions -- quench the fluorescence of these dyes, with consequent reductions in intensities, quantum yields, and lifetimes. As a result, the dyes can be used to detect these species. Another useful characteristic of these dyes is a capability for both two-photon and one-photon absorption. Typically, these dyes absorb single photons in the ultraviolet region of the spectrum (wavelengths fluorescence spectra identical to those obtained in response to excitation by single photons at half the corresponding wavelengths (300 to 400 nm). While many prior fluorescent dyes exhibit high quantum yields, solvent-polarity- dependent fluorescence behavior, susceptibility to quenching by certain chemical species, and/or two-photon fluorescence, none of them has the combination of all of these attributes. Because the present dyes do have all of these attributes

  20. Development of New Laser Protective Dyes

    Science.gov (United States)

    1993-07-31

    III; SBIR; Phase II; Laser; Laser Hazards; Laser Dye Synthesis; Ocular Protection; Ocular 16. PRICE CODE Hazard 17. SECURITY CLASSIFICATION 18...DyelPlastic Combinations Investigated during this Program DYE PLASTIC* Xmax (nrm) SS-1044 PETG 834 PC-- SS-1045 PC 777 SS-1049 PETG 1070 PC 3S-1101 PMMA 850/990...1151 PC 860 SS-1155 PETG 1060 PC SS-1159 PC 980 SS-1161 PC 755 PETG-Polyethylene tcrphtlmlate glycolate, PC-PolycazboWate, PMMA -polymethyl methacrybe

  1. Synthesis of azoimidazolium dyes with nitrous oxide.

    Science.gov (United States)

    Tskhovrebov, Alexander G; Naested, Lara C E; Solari, Euro; Scopelliti, Rosario; Severin, Kay

    2015-01-19

    A new method for the synthesis of industrially important azoimidazolium dyes is presented. The procedure is based on a reagent which is rarely used in the context of synthetic organic chemistry: nitrous oxide ("laughing gas"). N2O is first coupled to N-heterocyclic carbenes. Subsequent reaction with aromatic compounds through an AlCl3-induced C-H activation process provides azoimidazolium dyes in good yields. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Liquid crystal tunable photonic crystal dye laser

    DEFF Research Database (Denmark)

    Buss, Thomas; Christiansen, Mads Brøkner; Smith, Cameron

    2010-01-01

    We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium.......We present a dye-doped liquid crystal laser using a photonic crystal cavity. An applied electric field to the liquid crystal provides wavelength tunability. The photonic crystal enhances resonant interaction with the gain medium....

  3. Phytoremediation in education: textile dye teaching experiments.

    Science.gov (United States)

    Ibbini, Jwan H; Davis, Lawrence C; Erickson, Larry E

    2009-07-01

    Phytoremediation, the use of plants to clean up contaminated soil and water, has a wide range of applications and advantages, and can be extended to scientific education. Phytoremediation of textile dyes can be used as a scientific experiment or demonstration in teaching laboratories of middle school, high school and college students. In the experiments that we developed, students were involved in a hands-on activity where they were able to learn about phytoremediation concepts. Experiments were set up with 20-40 mg L(-1) dye solutions of different colors. Students can be involved in the set up process and may be involved in the experimental design. In its simplest forms, they use two-week-old sunflower seedlings and place them into a test tube of known volume of dye solution. Color change and/or dye disappearance can be monitored by visual comparison or with a spectrophotometer. Intensity and extent of the lab work depends on student's educational level, and time constraints. Among the many dyes tested, Evan's Blue proved to be the most readily decolorized azo dye. Results could be observed within 1-2 hours. From our experience, dye phytoremediation experiments are suitable and easy to understand by both college and middle school students. These experiments help visual learners, as students compare the color of the dye solution before and after the plant application. In general, simple phytoremediation experiments of this kind can be introduced in many classes including biology, biochemistry and ecological engineering. This paper presents success stories of teaching phytoremediation to middle school and college students.

  4. Degradation of textile dyes by cyanobacteria

    Directory of Open Access Journals (Sweden)

    Priscila Maria Dellamatrice

    Full Text Available Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black, and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.

  5. Degradation of textile dyes by cyanobacteria.

    Science.gov (United States)

    Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim

    Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  6. Chitosan derivatives as biosorbents for basic dyes.

    Science.gov (United States)

    Lazaridis, Nikolaos K; Kyzas, George Z; Vassiliou, Alexandros A; Bikiaris, Dimitrios N

    2007-07-03

    The scope of this study was to prepare and evaluate chitosan derivatives as biosorbents for basic dyes. This was achieved by grafting poly (acrylic acid) and poly (acrylamide) through persulfate induced free radical initiated polymerization processes and covalent cross-linking of the prepared materials. Remacryl Red TGL was used as the cationic dye. Equilibrium sorption experiments were carried out at different pH and initial dye concentration values. The experimental equilibrium data for each adsorbent-dye system were successfully fitted to the Langmuir, Freundlich and pH-dependent Langmuir-Freundlich sorption isotherms. Thermodynamic parameters of the adsorption process such as DeltaG degrees, DeltaH degrees, and DeltaS degrees were calculated. The negative values of free energy reflected the spontaneous nature of adsorption. The typical dependence of dye uptake on temperature and the kinetics of adsorption indicated the process to be chemisorption. The grafting modifications greatly enhanced the adsorption performance of the biosorbents, especially in the case of powdered cross-linked chitosan grafted with acrylic acid, which exhibited a maximum adsorption capacity equal to 1.068 mmol/g. Kinetic studies also revealed a significant improvement of sorption rates by the modifications. Diffusion coefficients of the dye molecule were determined to be of the order 10(-13) - 10(-12) m2/s. Furthermore, desorption experiments affirmed the regenerative capability of the loaded material.

  7. Chlorine disinfection of dye wastewater: Implications for a commercial azo dye mixture

    Energy Technology Data Exchange (ETDEWEB)

    Vacchi, Francine Inforcato; Albuquerque, Anjaina Fernandes; Vendemiatti, Josiane Aparecida; Morales, Daniel Alexandre [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil); Ormond, Alexandra B.; Freeman, Harold S. [Department of Textile Engineering, Chemistry, and Science, North Carolina State University, Raleigh, NC 27695-8301 (United States); Zocolo, Guilherme Juliao; Zanoni, Maria Valnice Boldrin [Departamento de Quimica Analitica, Universidade Estadual Paulista Julio de Mesquita Filho, Instituto de Quimica de Araraquara, Araraquara, SP 14801-970 (Brazil); Umbuzeiro, Gisela, E-mail: giselau@ft.unicamp.br [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil)

    2013-01-01

    Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC-ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1. -- Highlights: Black-Right-Pointing-Pointer Aqueous solutions of Disperse Red 1 were treated with chlorine. Black-Right-Pointing-Pointer The chlorination products of Disperse Red 1 were identified using LC-ESI-MS/MS. Black-Right-Pointing-Pointer Daphnia and Salmonella/microsome were employed for eco/genotoxicity testing. Black-Right-Pointing-Pointer The chlorinated dye was more mutagenic

  8. Optical properties of natural dyes on the dye-sensitized solar cells (DSSC) performance

    Science.gov (United States)

    Pratiwi, D. D.; Nurosyid, F.; Supriyanto, A.; Suryana, R.

    2016-11-01

    This study reported several natural dyes for application in dye-sensitized solar cells (DSSC). This study aims was to determine the effect of optical absorption properties of natural dyes on efficiency of DSSC. The sandwich structure of DSSC consist of TiO2 as working electrode, carbon layer as counter electrode, natural dyes as photosensitizer, and electrolyte as electron transfer media. The natural dyes used in this experiment were extracted from dragon fruit anthocyanin, mangosteen peels anthocyanin, and red cabbage anthocyanin. The absorbance of dyes solutions and the adsorption of the dye on the surface of TiO2 were characterized using UV-Vis spectrophotometer, the quantum efficiency versus wavelength was characterized using incident photon-to-current efficiency (IPCE) measurement system, and the efficiency of DSSC was calculated using I-V meter. UV-Vis characteristic curves showed that wavelength absorption of anthocyanin dye of red cabbage was 450 - 580 nm, anthocyanin of mangosteen peels was 400 - 480 nm, and anthocyanin of dragon fruit was 400 - 650 nm. Absorption spectra of the dye adsorption on the surface of TiO2 which was resulted in the highest absorbance of red cabbage anthocyanin. IPCE characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted quantum efficiency of 0.058%; 0.047%; and 0.043%, respectively at wavelength maximum about 430 nm. I-V characteristic curves with anthocyanin dye of red cabbage, mangosteen peels anthocyanin, and dragon fruit anthocyanin resulted efficiency of 0.054%; 0.042%; and 0.024%, respectively.

  9. Synergistic effect of Sr{sup 2+} and ReO{sub 4}{sup −} adsorption on hexadecyl pyridinium-modified montmorillonite

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Wuhui; Inoue, Akihiro; Hirajima, Tsuyoshi; Sasaki, Keiko, E-mail: keikos@mine.kyushu-u.ac.jp

    2017-02-01

    Highlights: • Simultaneous adsorption of Sr{sup 2+} and ReO{sub 4}{sup −} on HDPy–modified Mt was studied. • Considerable adsorption capacities of Sr{sup 2+} and ReO{sub 4}{sup −} were obtained on HDPy/Mt–0.92. • Desorption–adsorption is responsible for uptake of Sr{sup 2+} and ReO{sub 4}{sup −} on HDPy/Mt. • Simultaneous adsorption of Sr{sup 2+} and ReO{sub 4}{sup −} on HDPy/Mt is a synergistic process. - Abstract: Simultaneous adsorption of Sr{sup 2+} and ReO{sub 4}{sup −}, which are surrogates of {sup 90}Sr{sup 2+} and {sup 99m}TcO{sub 4}{sup −}, on hexadecyl pyridinium (HDPy{sup +})-modified montmorillonite (HDPy/Mt) was investigated. When the amount of HDPy{sup +} corresponding to 0.92 times the cation exchange capacity (CEC) of Mt was added, the obtained composite (HDPy/Mt–0.92) showed considerable adsorption capacities for Sr{sup 2+} and ReO{sub 4}{sup −}. Some HDPy{sup +} desorbed from the Mt layer in the presence of ReO{sub 4}{sup −}, providing negatively charged sites on the Mt surface for Sr{sup 2+} adsorption. The desorbed HDPy{sup +} interacted with ReO{sub 4}{sup −} and was trapped in the composite in the form of HDPy–ReO{sub 4}, resulting in adsorption of ReO{sub 4}{sup −}. At high initial concentrations of ReO{sub 4}{sup −}, the HDPy configuration changed after adsorption because of the desorption–adsorption process, which was supported by X-ray diffraction. Based on the results of X-ray photoelectron spectroscopy, in the binary system (i.e., Sr{sup 2+} and ReO{sub 4}{sup −}), Sr{sup 2+} uptake occurred in the interlayer space, while adsorption of ReO{sub 4}{sup −} occurred on the external surface and probably in the interlayer space. Desorption–adsorption and ion exchange account for Sr{sup 2+} uptake, while adsorption of ReO{sub 4}{sup −} was mainly attributed to desorption–adsorption. Compared with the one-adsorbate system, a synergistic effect of simultaneous adsorption of Sr{sup 2+} and Re

  10. Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics

    Science.gov (United States)

    El-Shishtawy, Reda M.; El-Zawahry, Manal M.; Abdelghaffar, Fatma; Ahmed, Nahed S. E.

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% owf of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics. PMID:25258720

  11. Nucleophilic addition of reactive dyes on amidoximated acrylic fabrics.

    Science.gov (United States)

    El-Shishtawy, Reda M; El-Zawahry, Manal M; Abdelghaffar, Fatma; Ahmed, Nahed S E

    2014-01-01

    Seven reactive dyes judiciously selected based on chemical structures and fixation mechanisms were applied at 2% of of shade on amidoximated acrylic fabrics. Amidoximated acrylic fabric has been obtained by a viable amidoximation process. The dyeability of these fabrics was evaluated with respect to the dye exhaustion, fixation, and colour strength under different conditions of temperature and dyeing time. Nucleophilic addition type reactive dyes show higher colour data compared to nucleophilic substitution ones. FTIR studies further implicate the binding of reactive dyes on these fabrics. A tentative mechanism is proposed to rationalize the high fixation yield obtained using nucleophilic addition type reactive dyes. Also, the levelling and fastness properties were evaluated for all dyes used. Excellent to good fastness and levelling properties were obtained for all samples irrespective of the dye used. The result of investigation offers a new method for a viable reactive dyeing of amidoximated acrylic fabrics.

  12. Adapting vat dye as an alternate dyeing agent for vegetable tanned ...

    African Journals Online (AJOL)

    This experiment was subdivided into three parts where various techniques for applying dyes were used. It proved successful, thus indicating that, with proper formulation, vat dye and its accompanying agents could perform effectively on protein fibre in leatherwork, just as it does on cellulose fibre in textiles.

  13. Disperse Dyes Based on Aminothiophenes: Their Dyeing Applications on Polyester Fabrics and Their Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Saleh Mohammed Al-Mousawi

    2013-06-01

    Full Text Available A series of monoazo disperse dyes derived from arylazothienopyridazines were synthesized. Fastness properties of dyed polyester samples were measured. Most of the dyed fabrics tested displayed excellent washing and perspiration fastness and moderate light fastness. Finally, the biological activity of the synthesized dyes against Gram positive bacteria, Gram negative bacteria and yeast were evaluated.

  14. Acid-base indicator properties of dyes from local plants I: Dyes from ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    ABSTRACT: The acid-base indicator properties of aqueous and ethanol extracts from calyces of H. sabdariffa (Zobo) and a dye obtained from the ripe fruits of Basella alba (Indian spinach), two local plants, were investigated. A purple coloured dye obtained from the ripe fruits of Basella alba showed a λmax at. 580nm ...

  15. Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

    Directory of Open Access Journals (Sweden)

    Shahid Mahmood

    2011-04-01

    Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

  16. Reactive dye extraction utilizing regenerated bleaching earth

    Directory of Open Access Journals (Sweden)

    M. Shahi

    2017-09-01

    Full Text Available Bentonite bleaching earth is utilized for purifying used motor oil through a recovery process in order to improve the quality and stability of the final product. Indeed, spent bleaching earth is generated due to adsorbing oil impurities. Polluted spent bleaching earth contains 20-40% (w/w oil and is flammable. Its disposal without pre-treatment leads to loss of oil along with environmental impacts. Accordingly, similar studies have been conducted since 1979 until now. This research was a laboratory study on reactive dye adsorption. Cleaning bleaching clay, thermal remediation and acid washing activation methods were utilized. Response surface methodology was used to design the experiments and determine the optimal parameters in order to run the dye adsorption process. The main experimental parameters have been concluded as temperature (200-800 °C, acid solution concentration (0.1-3 M, dye solution concentration (1-35 ppm, and ratio of activated earth to dye solution (0.1-2 %, w/w. Results revealed that dye adsorption process along with oil removal at a temperature of 650 °C, acid solution concentration of 0.83 M, dye solution concentration of 11.75 ppm and ratio of activated earth to dye solution of 1.52 % (w/w results in an adsorption efficiency of 68.57%. This removal efficiency is a bit higher than activated virgin bleaching earth and much higher than virgin bleaching earth, which has adsorption capacities of 66.75% and 51.56%, respectively. Considering this recycling process, the purified material is quite acceptable technically, environmentally and economically.

  17. Review of Recent Progress in Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Fan-Tai Kong

    2007-01-01

    Full Text Available We introduced the structure and the principle of dye-sensitized solar cell (DSC. The latest results about the critical technology and the industrialization research on dye-sensitized solar cells were reviewed. The development of key components, including nanoporous semiconductor films, dye sensitizers, redox electrolyte, counter electrode, and conducting substrate in dye-sensitized solar cells was reviewed in detail. The developing progress and prospect of dye-sensitized solar cells from small cells in the laboratory to industrialization large-scale production were reviewed. At last, the future development of DSC was prospective for the tendency of dye-sensitized solar cells.

  18. Benzamide porphyrins with directly conjugated and distal pyridyl or pyridinium groups substituted to the porphyrin macrocycles: Study of the photosensitising abilities as inducers of apoptosis in cancer cells under photodynamic conditions.

    Science.gov (United States)

    Sengupta, Devashish; Mazumdar, Zeaul Hoque; Mukherjee, Avinaba; Sharma, Debdulal; Halder, Amit Kumar; Basu, Samita; Jha, Tarun

    2017-11-13

    Amphiphilic porphyrin photosensitisers (PSs) having combinations of directly substituted pyridyl group(s) at the meso-position of a porphyrin macrocycle, and/or indirectly linked pyridyl groups as benzamide derivatives are reported. The compounds 5,10,15,20-tetrakis-(4-pyridylbenzamide)porphyrin (A.2), 5,10,15,20-tetra[N-(pyridine-4-yl)benzamidium] porphyrin (A.3), 5-mono-(4-pyridyl)-10,15,20-tris-(4-pyridylbenzamide)porphyrin (B.2) and 5-mono-(4-methylpyridinium)-10,15,20-tris-(4-pyridiniumbenzamide)porphyrin (B.3) were synthesised. The compounds were successfully characterised through UV-Vis, Emission, 1H NMR, and ESI-HRMS techniques. To evaluate the effect of this combination of directly conjugated and non-conjugated pyridyl/cationic pyridinium groups on the porphyrin macrocycle, the efficacy of the synthesised compounds was compared to a known standard 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin (TMPyP). These compounds show better efficacy (IC50's ranging between 0.66±0.04μM to 3.71±1.01μM) against A549 (human epithelial adenocarcinoma lung cancer) cell line under in vitro photodynamic conditions in comparison to MDA-MB-231 (breast cancer) (IC50's ranging between 3.7±0.087μM to 12.1±0.12μM) and Pa-1 (ovarian cancer) (IC50's ranging between 17.9±0.01μM to 42.45±0.02μM) cell lines. It was found that B.3, having a pyridinium group attached to the meso-position of the macrocycle along with three distal cationic pyridinium groups, independent of the porphyrinic electron delocalisation cycle, showed better photocytotoxic efficacy (IC50=0.66±0.04μM, A549 lung cancer cell line) and higher potential to promote apoptosis and hence better efficacy as PS towards cancer photodynamic therapy (PDT). The PDT activity of B.3 was further verified and established by various biological assays, viz. Annexin V assay, cell cycle assay, and reactive oxygen species (ROS) activity assay. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Physical and chemical investigations on natural dyes

    Science.gov (United States)

    Acquaviva, S.; D'Anna, E.; de Giorgi, M. L.; Della Patria, A.; Baraldi, P.

    2010-09-01

    Natural dyes have been used extensively in the past for many purposes, such us to colour fibers and to produce inks, watercolours and paints, but their use declined rapidly after the discovery of synthetic colours. Nowadays we witness a renewed interest, as natural dyes are neither toxic nor polluting. In this work, physical and chemical properties of four selected dyes, namely red (Madder), yellow (Weld and Turmeric) and blue (Woad) colours, produced by means of traditional techniques at the Museo dei Colori Naturali (Lamoli, Italy), have been investigated. The chromatic properties have been studied through the reflectance spectroscopy, a non-invasive technique for the characterisation of chromaticity. Reflection spectra both from powders and egg-yolk tempera models have been acquired to provide the typical features of the dyes in the UV-vis spectral range. Moreover, to assess the feasibility of laser cleaning procedures, tempera layers were investigated after irradiation with an excimer laser. Micro Raman spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-Ray analyses have complemented the survey, returning compositional and morphological information as well. Efforts have been made to give scientific feedback to the production processes and to support the research activity in the restoration of the artworks where these dyes were employed.

  20. Chromed Leather Dyeing Peculiarities when Deliming with Peracetic Acid

    Directory of Open Access Journals (Sweden)

    Kęstutis BELEŠKA

    2013-05-01

    Full Text Available The research was aimed to investigate the influence of deliming with peracetic acid on leather dyeing kinetics. Hydrophobic C.I. Acid Red 213 and hydrophilic C.I. Acid Red 423 dyes were used. Sorption of dye depends on hydrophobicity/hydrophility of dye and dyeing temperature. Equilibrium of process is reached faster using hydrophobic C.I. Acid Red 213 at 45 ºC. However, both control and experimental leather fibres adsorb more hydrophilic dye C.I. Acid Red 423 and this fact does not depend on temperature. The diffusion coefficient of dye C.I. Acid Red 423 calculated according to Weisz model is higher when dyeing conventional leather. The change of deliming method has influence on chromed leather dyeing but this influence is not significant. The adsorption ability of control leather fibres at 30 ºC and 45 ºC is higher using both dyes as compared to the dyeing the experimental one. The increase of dyeing temperature increases the adsorption ability independently on the sort of leather fibres. Such dependence of the adsorption ability on the temperature shows that hydrophobic action and van der Waals forces prevail between dye and fibres during dyeing process. The Gibbs energy changes show that adsorption of both dyes by leather fibres independently on their sort is a spontaneous process. The affinity of both dyes to conventional leather fibres is higher comparing with experimental one. The change of enthalpy is positive in all cases, and it means that the driving force of the dyeing is the change of entropy.DOI: http://dx.doi.org/10.5755/j01.ms.19.2.4431

  1. Quantum dot-dye hybrid systems for energy transfer applications

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Ting

    2010-07-01

    In this thesis, we focus on the preparation of energy transfer-based quantum dot (QD)-dye hybrid systems. Two kinds of QD-dye hybrid systems have been successfully synthesized: QD-silica-dye and QD-dye hybrid systems. In the QD-silica-dye hybrid system, multishell CdSe/CdS/ZnS QDs were adsorbed onto monodisperse Stoeber silica particles with an outer silica shell of thickness 2-24 nm containing organic dye molecules (Texas Red). The thickness of this dye layer has a strong effect on the total sensitized acceptor emission, which is explained by the increase in the number of dye molecules homogeneously distributed within the silica shell, in combination with an enhanced surface adsorption of QDs with increasing dye amount. Our conclusions were underlined by comparison of the experimental results with Monte-Carlo simulations, and by control experiments confirming attractive interactions between QDs and Texas Red freely dissolved in solution. New QD-dye hybrid system consisting of multishell QDs and organic perylene dyes have been synthesized. We developed a versatile approach to assemble extraordinarily stable QD-dye hybrids, which uses dicarboxylate anchors to bind rylene dyes to QD. This system yields a good basis to study the energy transfer between QD and dye because of its simple and compact design: there is no third kind of molecule linking QD and dye; no spacer; and the affinity of the functional group to the QD surface is strong. The FRET signal was measured for these complexes as a function of both dye to QD ratio and center-to-center distance between QD and dye by controlling number of covered ZnS layers. Data showed that fluorescence resonance energy transfer (FRET) was the dominant mechanism of the energy transfer in our QD-dye hybrid system. FRET efficiency can be controlled by not only adjusting the number of dyes on the QD surface or the QD to dye distance, but also properly choosing different dye and QD components. Due to the strong stability, our QD-dye

  2. Effect of Mixing Dyes and Solvent in Electrolyte Toward Characterization of Dye Sensitized Solar Cell Using Natural Dyes as The Sensitizer

    Science.gov (United States)

    Puspitasari, Nurrisma; Nurul Amalia, Silviyanti S.; Yudoyono, Gatut; Endarko

    2017-07-01

    Dye Sensitized Solar Cell (DSSC) using natural dyes (chlorophyll, curcumin from turmeric extract, and anthocyanin from mangosteen extract) have been successfully fabricated for determining the effect of variation natural dyes, mixing dyes and acetonitrile in electrolyte toward characterization of DSSC. DSSC consists of five parts namely ITO (Indium Tin Oxide) as a substrate; TiO2 as semiconductor materials; natural dyes as an electron donor; electrolyte as electron transfer; and carbon as a catalyst that can convert light energy into electric energy. Two types of gel electrolyte based on PEG that mixed with liquid electrolyte have utilized for analyzing the lifetime of DSSC. Type I used distilled water as a solvent whilst type II used acetonitrile as a solvent with addition of concentration of KI and iodine. The main purpose of study was to investigate influence of solvent in electrolyte, variation of natural dyes and mixing dyes toward an efficiency that resulted by DSSC. The result showed that electrolyte type II is generally better than type I with efficiency 0,0556 and 0,0456 %, respectively. An efficiency values which resulted from a variation of mixed three natural dyes showed the greatest efficiency compared to mixed two natural dyes and one dye, with an efficiency value can be achieved at 0,0194 % for chlorophyll; 0,111 % for turmeric; 0,0105 % for mangosteen; 0,0244% (mangosteen and chlorophyll); 0,0117 % (turmeric and mangosteen); 0,0158 % (turmeric and chlorophyll); and 0.0566 % (mixed three natural dyes).

  3. In-situ Decolorization of Residual Dye Effluent in Textile Jet Dyeing Machine by Ozone

    Directory of Open Access Journals (Sweden)

    Irfan Ahmed Shaikh

    2014-12-01

    Full Text Available In this study, a new idea of decolourization was investigated in which residual dyeing effluent from textile dyeing process was treated using O3 in the same machine where it was generated. The novelty comes from the idea of doing dyeing and treatment simultaneously. At the completion of dyeing process, O3 gas was injected directly into the machine to remove colour and COD from the wastewater. To evaluate the effectiveness of new method, pilot-scale studies were performed, and decolourization of residual dyeing effluents containing C.I. Reactive Orange 7, C.I. Reactive Blue 19, and C.I. Reactive Black 5 was carried out in specially built textile jet dyeing machine. The results showed that almost 100% colour removal and 90% COD reduction were achieved when process conditions such as pH, dye concentration (mg/L, ozone production rate (g/hr, and temperature were optimized. The study concludes that new method has a great potential to eliminate the need of a separate end-of-the-pipe wastewater treatment system, thus offering an on-site and cost-effective solution.

  4. Dyeing of Silk with Anthocyanins Dyes Extract from Liriope platyphylla Fruits

    Directory of Open Access Journals (Sweden)

    Huayin Wang

    2014-01-01

    Full Text Available A new source of natural anthocyanins dyes, from Liriope platyphylla fruit, is proposed. This paper analyzes the dye extracts, the primary color components of the extracts, the color features of the extracts under different pH conditions, and their application in silk dyeing. The research shows that, nine anthocyanins are found in  L. platyphylla fruits by analyzing the results of the HPLC/DAD, MS, and MS/MS spectra. The five major anthocyanins related to delphinidin, petunidin, and malvidin derivatives take up 91.72% of total anthocyanin contents. The color of the solution is red under acidic condition (pH < 3.0 and stays in yellow under alkaline condition with pH values above 7.0. The dye extracts applied to silk fabric with mordant free dyeing show different color under different pH conditions, changing between purple, blue, green, and yellow. However, the dyed colors is light and the dyeing rate is low. Metal mordant such as Sn in chelation enhances the dye depth and improves the fastness of the dyed silk fabrics, especially in silk fabrics dyed by premordanting and metamordanting.

  5. Effectiveness of dye sensitised solar cell under low light condition using wide band dye

    Energy Technology Data Exchange (ETDEWEB)

    Sahmer, Ahmad Zahrin, E-mail: ahmadzsahmer@gmail.com; Mohamed, Norani Muti, E-mail: noranimuti-mohamed@petronas.com.my; Zaine, Siti Nur Azella, E-mail: ct.azella@gmail.com [Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak (Malaysia)

    2015-07-22

    Dye sensistised solar cell (DSC) based on nanocrystalline TiO{sub 2} has the potential to be used in indoor consumer power application. In realizing this, the DSC must be optimized to generate power under low lighting condition and under wider visible light range. The use of wide band dye N749 which has a wider spectrum sensitivity increases the photon conversion to electron between the visible light spectrums of 390nm to 700nm. This paper reports the study on the effectiveness of the dye solar cell with N749 dye under low light condition in generating usable power which can be used for indoor consumer application. The DSC was fabricated using fluorine doped tin oxide (FTO) glass with screen printing method and the deposited TiO{sub 2} film was sintered at 500°C. The TiO{sub 2} coated FTO glass was then soaked in the N749 dye, assembled into test cell, and tested under the standard test condition at irradiance of 1000 W/m{sup 2} with AM1.5 solar soaker. The use of the 43T mesh for the dual pass screen printing TiO{sub 2} paste gives a uniform TiO{sub 2} film layer of 16 µm. The low light condition was simulated using 1/3 filtered irradiance with the solar soaker. The fabricated DSC test cell with the N749 dye was found to have a higher efficiency of 6.491% under low light condition compared to the N719 dye. Under the standard test condition at 1 sun the N749 test cell efficiency is 4.55%. The increases in efficiency is attributed to the wider spectral capture of photon of the DSC with N749 dye. Furthermore, the use of N749 dye is more effective under low light condition as the V{sub OC} decrement is less significant compared to the latter.

  6. Third row metal complexes as an alternative dye in dye sensitized solar cell system

    Science.gov (United States)

    Wahyuningsih, S.; Ramelan, A. H.; Badriyah, I.; Kristy, I. O.; Dewi, N. S.; Rahardjo, S. B.

    2013-10-01

    Copper(II), Cobalt (II) and Iron (II) complexes as photosensitizer on Dye Sensitized Solar Cell (DSSC) had been investigated. The aim of this research is to find out the respond addition of those dyes on FTO/TiO2 (FTO = fluorine Tin Oxide) thin film to visible light and the effect of various third row complexes to DSSC performance. Slip casting method was used to fabricate FTO/TiO2 and FTO/carbon thin film. The result from FTO/TiO2 UV-Vis spectra show no absorption on visible light. Dye solution was synthesized from free metal ions of Cu(II), Co(II), and Fe(II) in methanol with diphenylamine (dpa), 2,2,bypiridine (bpy), 1,10, phenathroline (phen), 4,4'-dicarboxylic acid-2,2'-bipyridine (dcbq), and anthocyanin (ant) ligands, respectively. UV-Vis spectrophotometry was used to identify FTO/TiO2/dye with various sensitizer dyes. The performance of DSSC was determined by I (current) - V (voltage) curve using Keithley 2602 A System Source. In this research, DSSCs are able to convert photon energy become electrical energy. Dye used in DSSC is greatly effect in photon to current efficiency (IPCE). The greater absorption in visible region of alternative dye used gains higher IPCE spectra. TiO2 character can help spread the absorption in whole visible region. The nanosize mesoporous TiO2 of TiO2/SiPA/CoII-PAR (SiPA = silylpropilamine) have greater value than P25 TiO2/SiPA-CoII-PAR. The SiPA/FeII-PAR and SiPA/CoII-PAR dyes are better dye than tpa.

  7. Oxidative degradation of azo dyes using tourmaline.

    Science.gov (United States)

    Wang, Cuiping; Zhang, Yanwei; Yu, Li; Zhang, Zhiyuan; Sun, Hongwen

    2013-09-15

    This study aimed to investigate the catalyzed degradation ability of tourmaline on the dyes methylene blue (MB), rhodamine B (RhB), and congo red (CR) at different pH values. Interestingly, tourmaline strongly adsorbed anionic dyes, but it did not adsorb cationic dyes. When H₂O₂ was introduced into the tourmaline-dye systems, the degradation percentage for CR catalysis by tourmaline was lower than the percentage of adsorption, whereas the opposite was true for MB and RhB systems. Notably, the catalyzed degradation decreased from 100% to 45% for MB, 100% to 15% for RhB and 100% to 25% for CR as the pH increased from 3.0 to 10.0, respectively, which was much greater than the degradation obtained for previously reported materials at pH values ranging from 4.0 to 10.0. Tourmaline catalytically degraded the dyes over a broad range of pH values, which was attributed to tourmaline automatically adjusting the pH of the dye solutions to approximately 5.5 from an initial range of 4.2-10.0. An electron paramagnetic resonance spin trapping technique observed peroxyl (ROO·) and alkoxy (RO·) or alkyl (R·) radicals originated from the attack of ·OH radicals and O₂(·-) radicals, indicating that these radicals were involved in the catalyzed degradation of MB. Importantly, four intermediate products of MB at m/z 383, 316, 203 and 181 were observed by LC/MS. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Continuous-wave organic dye lasers and methods

    Energy Technology Data Exchange (ETDEWEB)

    Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

    2014-09-16

    An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

  9. Novel Tunable Dye Laser for Lidar Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A tunable dye laser for Lidar detection will be fabricated based on the innovative dye-doped Holographic Polymer Dispersed Liquid Crystals (HPDLC) technology. The...

  10. Continuous-wave organic dye lasers and methods

    Science.gov (United States)

    Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

    2014-09-16

    An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

  11. The Ideal Solvent for Paper Chromatography of Food Dyes.

    Science.gov (United States)

    Markow, Peter G.

    1988-01-01

    Uses paper chromatography with food dyes to provide a simple and inexpensive basis for teaching chromatography. Provides experimental methodology and tabled results. Includes a solvent system comparison (Rf) for seven dyes and twenty-two solvents. (MVL)

  12. Unconsumed precursors and couplers after formation of oxidative hair dyes

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Søsted, Heidi; Johansen, Jeanne Duus

    2006-01-01

    Contact allergy to hair dye ingredients, especially precursors and couplers, is a well-known entity among consumers having hair colouring done at home or at a hairdresser. The aim of the present investigation was to estimate consumer exposure to some selected precursors (p-phenylenediamine, toluene......-2,5-diamine) and couplers (3-aminophenol, 4-aminophenol, resorcinol) of oxidative hair dyes during and after hair dyeing. Concentrations of unconsumed precursors and couplers in 8 hair dye formulations for non-professional use were investigated, under the conditions reflecting hair dyeing. Oxidative...... hair dye formation in the absence of hair was investigated using 6 products, and 2 products were used for experimental hair dyeing. In both presence and absence of hair, significant amounts of unconsumed precursors and couplers remained in the hair dye formulations after final colour development. Thus...

  13. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy.

    Science.gov (United States)

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-07-22

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells.

  14. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells

    Science.gov (United States)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2014-07-01

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  15. RISK ASSESSMENT FOR THE DYE AND PIGMENT ...

    Science.gov (United States)

    This risk assessment calculates the maximum loadings of constituents found in dyes and pigment industries waste streams which can be disposed in different types of waste management units without causing health benchmarks to be exceeded at plausible receptor locations. The assessment focuses on potential risks from volatilization and leaching to groundwater of constituents disposed in surface impoundments and landfills with either clay liners or composite liners. This product will be used by EPA decision makers to assist in determining whether certain waste streams generated by the dyes and pigments industries should be designated as hazardous.

  16. Tunability of optofluidic distributed feedback dye lasers

    DEFF Research Database (Denmark)

    Gersborg-Hansen, Morten; Kristensen, Anders

    2007-01-01

    We investigate the tunability of optofluidic distributed feedback (DFB) dye lasers. The lasers rely on light-confinement in a nano-structured polymer film where an array of nanofluidic channels constitutes a third order Bragg grating DFB laser resonator with a central phase-shift. The lasers...... are operated by filling the DFB laser resonator with a dye solution by capillary action and optical pumping with a frequency doubled Nd: YAG laser. The low reflection order of the DFB laser resonator yields low out-of-plane scattering losses as well as a large free spectral range (FSR), and low threshold...

  17. Waste Water Treatment of Dye Contamination

    Directory of Open Access Journals (Sweden)

    Pattana Boonyaprapa

    2009-01-01

    Full Text Available The objectives of this research were to study tie-dye process data and wastewater characteristics from 60 entrepreneurs, and to study the colour density treatment in pilot scale by using upflow anaerobic filters. From 60 filled-out questionnaires, it was found that all tie-dye entrepreneurs used reactive dyes by a hot method. Ninety-eight percent of the tie-dye enterpreneurs produced wastewater at the rate of not more than 1500 liters per day. All of them lacked tie-dye wastewater treatment systems. Eighty-five percent of tie-dye entrepreneurs agreed that there must be wastewater treatment before release into the environment. From group discussions, it was found that the entrepreneurs realized the wastewater problem and wanted to carry out environment friendly tie-dyeing. Our study demonstrated that the average value of the colour density, chemical oxygen demand (COD, total dissolved solids (TDS and pH of the wastewater characteristics were 170 SU (space units, 1584 mg/l, 2487 mg/l and 8, respectively. For the upflow anaerobic filter, 5 sets of experiments, with 24 hours retention time, were designed, with 0, 1, 2, 3 and 4 % of cow’s feces ferment, respectively (sets 1st-5th. The result showed decreasing colour densities from 170 SU to 160 SU (dark colour, 60 SU (very light colour, 12 SU (no colour, 10 SU (no colour and 10 SU (no colour, respectively. We conclude that the upflow anaerobic filter, containing 2% cow’s feces ferment is an efficient way to reduce colour density of the wastewater. Mixing cow’s feces ferment with tie-dye wastewater increased COD and TDS in wastewater. Mean COD was increased by residual organic matter from 1584 mg/l (before treatment to (after-treatment, sets 2nd- 5th 1600 mg/l, 1680 mg/l, 1710 mg/l and 1750 mg/l, respectively. COD aftertreatment was higher than the industrial effluence standard (400 mg/l. Further treatment COD might include wetland procedures. TDS was increased by some residual organic matter

  18. A high-light-harvesting-efficiency coumarin dye for stable dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.S.; Cui, Y.; Hara, K. [National Institute of Advanced Industrial, Science and Technology (AIST), Tsukuba, Ibaraki (Japan); Dan-oh, Y.; Kasada, C.; Shinpo, A. [Hayashibara Biochemical Laboratories, Inc., Okayama (Japan)

    2007-04-20

    A new coumarin dye for use in dye-sensitized solar cells (DSSCs) is reported. It exhibits near-unity light harvesting efficiency and incident photon-to-electron conversion efficiency over a wide spectral region in 6 {mu}m transparent TiO{sub 2} films. DSSCs based on this metal-free organic dye show long-term stability and power-conversion efficiencies of around 6 % under continuous light-soaking stress for up to 1000 h. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  19. Red photoluminescence emission of laser dye doped DNA and PMMA

    Science.gov (United States)

    Yu, Zhou; Hagen, Josh A.; Grote, James G.; Steckl, Andrew J.

    2006-02-01

    DNA and PPMA were doped with the laser dye sulforhodamine 640. Red emission was observed from both dye-doped DNA and PMMA upon photoexcitation. Photoluminescence (PL) emission was studied as a function of dye concentration. The maximum PL intensity of dye in DNA host material is at least 17 times higher than that in PMMA. The DNA host shows higher doping concentration without optical quenching than PMMA does.

  20. Removal of textile dyes with biopolymers xanthan and alginic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lozano-Alvarez, J.; Jauregui-Rincon, J.; Mendoza-Diaz, G.; Rodriguez-Vazquez, G.; Frausto-Reyes, C.

    2009-07-01

    Textile industry is an important activity that provides considerable benefits to people, but unfortunately dyeing of yarn and cloth produces pollution of water, a resource that is valuable and scarce. Dyeing of textiles fibers is an inefficient process, in view of the fact that approximately ten percent of total dye is thrown to municipal sewage. Although different treatment systems are applied to wastewater, dyes are resistant to physical, chemical and biological factors because of the way they are designed. (Author)

  1. Solid-liquid equilibria for a pyrrolidinium-based common-cation ternary ionic liquid system, and for a pyridinium-based ternary reciprocal ionic liquid system: an experimental study and a thermodynamic model.

    Science.gov (United States)

    Mirarabrazi, Meysam; Stolarska, Olga; Smiglak, Marcin; Robelin, Christian

    2017-12-20

    The present paper describes an experimental study and a thermodynamic model for the phase diagrams of the common-cation ternary system [C 4 MPyrr]Cl-[C 4 MPyrr]Br-[C 4 MPyrr]BF 4 (where [C 4 MPyrr] refers to 1-butyl-1-methyl-pyrrolidinium) and of the ternary reciprocal system [C 2 Py], [C 4 Py]‖Cl, Br (where [C n Py] refers to 1-alkyl-pyridinium). Phase equilibria were measured by Differential Scanning Calorimetry (DSC) for two isoplethal sections in the common-cation pyrrolidinium-based ternary system. Phase diagram measurements were recently performed for the four common-ion binary subsystems and the two diagonal sections in the pyridinium-based ternary reciprocal system. In each case, the Modified Quasichemical Model was used to model the liquid solution, and the Compound Energy Formalism was used for the relevant solid solutions. For the ternary reciprocal system, the missing thermodynamic properties of the pure compounds were assessed using the Volume-based Thermodynamics (VBT) from Glasser and Jenkins, making it possible to estimate the exchange Gibbs free energy for the reaction [C 2 Py]Br (liquid) + [C 4 Py]Cl (liquid) = [C 2 Py]Cl (liquid) + [C 4 Py]Br (liquid). The experimental diagonal sections [C 4 Py]Br-[C 2 Py]Cl and [C 4 Py]Cl-[C 2 Py]Br were satisfactorily reproduced using solely the optimized model parameters for the four common-ion binary subsystems.

  2. 2-[(Diisopropylthiophosphorylamino]pyridinium tetrafluoroborate

    Directory of Open Access Journals (Sweden)

    Christian Holzhacker

    2012-06-01

    Full Text Available The title compound, C11H20N2PS+·BF4−, is a salt of 2-(diisopropylthiophosphorylaminopyridine, a chelating bidentate ligand that furnishes an S atom as a soft donor and a pyridine N atom as a hard atom for transition-metal complexation. The title salt crystallizes with two formula units in the asymmetric unit. The two independent cations are protonated at the pyridine N atoms and have the S atoms syn-oriented to them so as to form bent intramolecular N—H...S hydrogen bonds, one of which one is bifurcated by involving also an N—H...F interaction. The phosphorylamino NH groups form near linear hydrogen bonds to proximal tetrafluoroborate anions. Five weak C—H...F and three weak C—H...S interactions link the constituents into a three-dimensional framework. As a result of the crystal packing, the two cations differ notably in conformation, as can be seen from the S—P—N—C torsion angles of −18.7 (1° in the first and −35.1 (1° in the second cation.

  3. Integrated and sequential anaerobic/aerobic biodegradation of azo dyes

    NARCIS (Netherlands)

    Tan, N.G.C.

    2001-01-01

    Azo dyes constitute a major class of environmental pollutants accounting for 60 to 70% of all dyes and pigments used. These compounds are characterized by aromatic moieties linked together with azo groups (-N=N-). The release of azo dyes into the environment is a concern due to coloration

  4. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... colourants; they are usually not easily biodegraded. Dye colours are visible in water at concentration as low as 1 mg/L, whereas textile processing waste water, normally contain more than 10-200 mg/L dye concentration, resulting in aesthetic problems (O'Neil et al., 1999). The toxicity of dye industrial waste ...

  5. Optimization of Crystal Violet dye removal from aqueous solution ...

    African Journals Online (AJOL)

    Batch adsorption process involving use of groundnut shell (GS) and orange peel (OP) as adsorbents was employed for the removal of carcinogenic Crystal Violet dye from aqueous solution. Studies were carried out as function of contact time, sorbent dosage, initial dye concentration and pΗ of the dye solution with a view of ...

  6. Page 1 PRELIMINARY INVESTIGATION OF DYE-ION ...

    African Journals Online (AJOL)

    forms were identified. Then acid buffers" and alkaline buffers' of appropriate pH values were prepared for use with each dye. A typical potentiometric titration result for a dye is shown in Fig. 1 for bromopyrogallol red while the dependence of its absorbance on pH is shown in Fig. 2. Stable pH values for the listed dyes are.

  7. Biotreatment of anthraquinone dye Drimarene Blue K2RL

    African Journals Online (AJOL)

    ISHIOMA

    Drimarene Blue (Db) K2RL is a reactive anthraquinone dye, used extensively in textile industry, due to poor adsorbability to textile fiber; it has a higher exhaustion rate in wastewater. The dye is toxic, carcinogenic, mutagenic and resistant to degradation. Decolorization of this dye was studied in two different systems.

  8. Fluorescence of dyes adsorbed on highly organized nanostructured gold surfaces

    NARCIS (Netherlands)

    Levi, S.; Mourran, Ahmed; Spatz, Joachim P.; van Veggel, F.C.J.M.; Reinhoudt, David; Möller, M.

    2002-01-01

    It is shown that fluorescent dyes can be adsorbed selectively on gold nanoparticles which are immobilized on a glass substrate and that the fluorescence originating from the adsorbed dyes exhibits significantly less quenching when compared to dyes adsorbed on bulk gold. Self-assembled monolayers of

  9. Comparison of dye decolorization efficiencies of indigenous fungal ...

    African Journals Online (AJOL)

    Different physicochemical cultural conditions were optimized for azo dye removal by using Acid Red 151 as a model dye, being of high consumer demand and usage during the present study. The three fungal strains having the dye removal abilities, Aspergillus niger SA1, Aspergillus flavus SA2 and Aspergillus terreus SA3 ...

  10. Synthesis and application of hetaryl disazo disperse dyes derived ...

    African Journals Online (AJOL)

    Also, it was found that the wash fastness property, which is an indicator whether a dye could have affinity for a textile fabric or not, have excellent ratings of 5. From these results, it can be concluded that the best of these disazo dye compounds could be commercially important in the textile industry. Keywords: Disazo dyes ...

  11. 40 CFR 721.9717 - Azo monochloro triazine reactive dye.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Azo monochloro triazine reactive dye... Substances § 721.9717 Azo monochloro triazine reactive dye. (a) Chemical substance and significant new uses... reactive dye (PMN P-96-238) is subject to reporting under this section for the significant new uses...

  12. 40 CFR 721.2527 - Substituted diphenylazo dye (generic name).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted diphenylazo dye (generic... Specific Chemical Substances § 721.2527 Substituted diphenylazo dye (generic name). (a) Chemical substance... substituted diphenylazo dye (PMN P-95-514) is subject to reporting under this section for the significant new...

  13. 40 CFR 721.5915 - Polysubstituted phenylazopolysubstitutedphenyl dye.

    Science.gov (United States)

    2010-07-01

    ... phenylazopolysubstitutedphenyl dye. 721.5915 Section 721.5915 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.5915 Polysubstituted phenylazopolysubstitutedphenyl dye. (a) Chemical... as a polysubstituted phenylazopolysubstitutedphenyl dye (PMN P-93-658) is subject to reporting under...

  14. 40 CFR 721.5917 - Phenyl azo dye (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenyl azo dye (generic). 721.5917... Substances § 721.5917 Phenyl azo dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a phenyl azo dye (PMN P-02-17) is subject to...

  15. 40 CFR 721.988 - Pyrazolone azomethine dye (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Pyrazolone azomethine dye (generic... Substances § 721.988 Pyrazolone azomethine dye (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a pyrazolone azomethine dye...

  16. Biotreatment of anthraquinone dye Drimarene Blue K 2 RL | Siddiqui ...

    African Journals Online (AJOL)

    Drimarene Blue (Db) K2RL is a reactive anthraquinone dye, used extensively in textile industry, due to poor adsorbability to textile fiber; it has a higher exhaustion rate in wastewater. The dye is toxic, carcinogenic, mutagenic and resistant to degradation. Decolorization of this dye was studied in two different systems.

  17. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... Key words: Bioremediation, decolourization, textile dye, Bacillus cereus. INTRODUCTION. Dyes are organic chemical compounds, which impart colour to other materials by saturating them in aqueous solution. Synthetic dyes have a wide application in the food, pharmaceutical, textile, leather, cosmetics ...

  18. Taming fluorescence yield of dye insensitive to temperature by non ...

    Indian Academy of Sciences (India)

    2014-02-12

    Feb 12, 2014 ... ... due to the heat generated by circulation pumps and non-radiative decay processes of excited dye molecules. The QYF of RhB dye in water was found to be not sensitive to temperature in the practical operating region 16–25°C of dye laser by adopting supramolecular route to form an inclusion complex of ...

  19. 17 EFFECTS OF MORDANTING METHODS OF DYE FROM ...

    African Journals Online (AJOL)

    Frederick Iraki

    dyeing woven cotton with natural dyes from the leaves of Vernonia amygdalina. The effects analyzed are color fastness ... INTRODUCTION. In Uganda, plants have traditionally been utilized as a source of colorants for dyeing mats, ropes and other home based materials for a long time. These plants are a potential source of ...

  20. Decolourisation of chemically different dyes by enzymes from spent ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-01-04

    Jan 4, 2010 ... 042 Afr. J. Biotechnol. microorganisms degrade dyes by azoreductase activity and this leads to the formation of aromatic amines which pose a more serious biotoxic threat than the original azo dyes (Chung and Stevens, 1993). The biodegradation of dyes by white rot fungi and their ligninolytic enzyme sys-.

  1. 21 CFR 864.1850 - Dye and chemical solution stains.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dye and chemical solution stains. 864.1850 Section... solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures of synthetic or natural dyes or nondye chemicals in solutions used in staining cells and tissues for diagnostic...

  2. Sequestration of Congo red Dye from Aqueous Solution using ...

    African Journals Online (AJOL)

    The adsorption of Congo red dye in aqueous solution using locally sourced almond shell adsorbent was investigated in this study. The effect of various factors such as contact time, initial dye concentration and adsorbent dosage on the adsorption capacity of the adsorbent was studied. The adsorption of Congo red dye was ...

  3. Two dye combinations suitable for two-color/two-dye laser-induced fluorescence thermography for ethanol

    Science.gov (United States)

    Fenner, Andreas; Stephan, Peter

    2017-06-01

    This paper presents two dye combinations suitable for two-color/two-dye laser-induced fluorescence thermography for ethanol. Besides the temperature dependency of the fluorescence, the influences of laser fluence, dye concentration, pressure, dissolved air, and photobleaching are also discussed. The experimental data are compared with models and data available in literature. Based on this, parameter ranges for two-color/two-dye laser-induced fluorescence thermography applications can be determined.

  4. Dye-sensitized solar cells with natural dyes extracted from achiote seeds

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ortiz, N.M.; Vazquez-Maldonado, I.A.; Azamar-Barrios, J.A.; Oskam, G. [Departamento de Fisica Aplicada, CINVESTAV-IPN, Merida, Yuc. 97310 (Mexico); Perez-Espadas, A.R.; Mena-Rejon, G.J. [Laboratorio de Quimica Organica de Investigacion, Facultad de Quimica, Universidad Autonoma de Yucatan, Merida, Yuc. 97150 (Mexico)

    2010-01-15

    We have explored the application of natural dyes extracted from the seeds of the achiote shrub (Bixa orellana L.) in dye-sensitized solar cells (DSCs). The main pigments are bixin and norbixin, which were obtained by separation and purification from the dark-red extract (annatto). The dyes were characterized using {sup 1}H-NMR, FTIR spectroscopy, and UV-Vis spectrophotometry. Solar cells were prepared using TiO{sub 2} and ZnO nanostructured, mesoporous films and the annatto, bixin, and norbixin as sensitizers. The best results were obtained with bixin-sensitized TiO{sub 2} solar cells with efficiencies of up to 0.53%, illustrating the importance of purification of dyes from natural extracts. (author)

  5. Dye-Sensitized Solar Cells (DSSCs) reengineering using TiO2 with natural dye (anthocyanin)

    Science.gov (United States)

    Subodro, Rohmat; Kristiawan, Budi; Ramelan, Ari Handono; Wahyuningsih, Sayekti; Munawaroh, Hanik; Hanif, Qonita Awliya; Saputri, Liya Nikmatul Maula Zulfa

    2017-01-01

    This research on Dye-Sensitized Solar Cells (DSSCs) reengineering was carried out using TiO2 with natural dye (anthocyanin). The fabrication of active carbon layer/TiO2 DSSC solar cell was based on natural dye containing anthocyanins such as mangosteen peel, red rose flower, black glutinous rice, and purple eggplant peel. DSSC was prepared with TiO2 thin layer doped with active carbon; Natural dye was analyzed using UV-Vis and TiO2 was analyzed using X-ray diffractometer (XRD), meanwhile scanning electron microscope (SEM) was used to obtain the size of the crystal. Keithley instrument test was carried out to find out I-V characteristics indicating that the highest efficiency occurred in DSSCs solar cell with 24-hour soaking with mangosteen peel 0.00047%.

  6. Dye linked conjugated homopolymers: using conjugated polymer electroluminescence to optically pump porphyrin-dye emission

    DEFF Research Database (Denmark)

    Nielsen, K.T.; Spanggaard, H.; Krebs, Frederik C

    2004-01-01

    Zinc-porphyrin dye molecules were incorporated into the backbone of a conjugated polymer material by a method, which allowed for the incorporation of only one zinc-porphyrin dye molecule into the backbone of each conjugated polymer molecule. The electronic properties of the homopolymer were....... Electroluminescent devices of the homopolymer itself and of the zinc-porphyrin containing polymer were prepared and the nature of the electroluminescence was characterized. The homopolymer segments were found to optically pump the emission of the zinc-porphyrin dye moities. The homopolymer exhibits blue......-green emission and the zinc-porphyrin linked homopolymers emit near-infrared/infrared light. This was demonstrated to be due to electroluminescence pumping of the zinc-porphyrin moieties that were covalently linked to homopolymer material. When only one zinc-porphyrin dye was incorporated into the backbone...

  7. Development auxiliaries for dyeing polyester with disperse dyes at low temperatures

    Science.gov (United States)

    Carrion-Fite, F. J.; Radei, S.

    2017-10-01

    High-molecular weight organic compounds known as carriers are widely used to expedite polyester dyeing at atmospheric pressure at 100 °C. However, carriers are usually poorly biodegradable and can partially plasticize fibres. Also, dyeing at temperatures above 100 °C in the absence of a carrier entails using expensive equipment. In this work, we developed an alternative method for dyeing polyester at temperatures below 100 °C that reduces energy expenses, dispenses with the need to invest in new equipment and avoids the undesirable effects of non-biodegradable carriers. The method uses disperse dyes in a microemulsion containing a low proportion of a non-toxic organic solvent and either of two alternative development auxiliaries (coumarin and o-vanillin) that is prepared with the aid of ultrasound.

  8. Dye-sensitized photopolymerization of N, N ...

    Indian Academy of Sciences (India)

    The rate of polymerization is proportional to [MBA] and [AH2]. Kinetic results indicate that semi-quinone (DH) dye radical and semi-oxidized form () of ascorbic acid are unable to initiate polymerization. Formation of H2O2 is proposed and confirmed. A suitable mechanism is proposed in accordance with experimental ...

  9. Dye-sensitised solar cell (artificial photosynthesis)

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2006-02-01

    Full Text Available is the nano- crystalline TiO2dye- sensitised solar cell (DSC), in conjunction with several new concepts, such as nanotechnology and molecular devices. An efficient and low-cost cell can be produced by using simple materials. The production process generates...

  10. SOLID STATE PHOTOELECTROCHEMICAL CELL BASED ON DYE ...

    African Journals Online (AJOL)

    isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II) (N719) dye has been constructed and characterized. The current density–voltage characteristics in the dark and under white light illumination and action spectra under monochromatic ...

  11. COLOR POLLUTION CONTROL IN TEXTILE DYEING INDUSTRY ...

    African Journals Online (AJOL)

    a

    E-mail: ssreedharreddy@yahoo.com. COLOR POLLUTION CONTROL IN TEXTILE DYEING INDUSTRY EFFLUENTS. USING TANNERY SLUDGE DERIVED ACTIVATED CARBON. Sajjala Sreedhar Reddy1∗, Bijjam Kotaiah2 and Nanaga Siva Prasad Reddy3. 1Adama University, Faculty of Technology, Post Box No. 1888 ...

  12. Micro-Cavity Fluidic Dye Laser

    DEFF Research Database (Denmark)

    Helbo, Bjarne; Kristensen, Anders; Menon, Aric Kumaran

    2003-01-01

    We have successfully designed, fabricated and characterized a micro-cavity fluidic dye laser with metallic mirrors, which can be integrated with polymer based lab-on-a-chip microsystems without further processing steps. A simple rate-equation model is used to predict the average pumping power...

  13. Removal of Triphenylmethane Dyes by Bacterial Consortium

    Directory of Open Access Journals (Sweden)

    Jihane Cheriaa

    2012-01-01

    Full Text Available A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila-(CM-4 was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L and malachite green (50 mg/L dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes.

  14. (Hair-dye) and Renal Impairment

    African Journals Online (AJOL)

    Introduction: Paraphenylenediamine (PPD) is widely used in hair dyes and cosmetic skin application. PPD intoxication following oral ingestion could be an important cause of ARF in Sudan, Morocco and the Indian Subcontinent. Repeated and prolonged exposure to PPD may also be associated with Chronic Kidney ...

  15. Removal of Triphenylmethane Dyes by Bacterial Consortium

    Science.gov (United States)

    Cheriaa, Jihane; Khaireddine, Monia; Rouabhia, Mahmoud; Bakhrouf, Amina

    2012-01-01

    A new consortium of four bacterial isolates (Agrobacterium radiobacter; Bacillus spp.; Sphingomonas paucimobilis, and Aeromonas hydrophila)-(CM-4) was used to degrade and to decolorize triphenylmethane dyes. All bacteria were isolated from activated sludge extracted from a wastewater treatment station of a dyeing industry plant. Individual bacterial isolates exhibited a remarkable color-removal capability against crystal violet (50 mg/L) and malachite green (50 mg/L) dyes within 24 h. Interestingly, the microbial consortium CM-4 shows a high decolorizing percentage for crystal violet and malachite green, respectively, 91% and 99% within 2 h. The rate of chemical oxygen demand (COD) removal increases after 24 h, reaching 61.5% and 84.2% for crystal violet and malachite green, respectively. UV-Visible absorption spectra, FTIR analysis and the inspection of bacterial cells growth indicated that color removal by the CM-4 was due to biodegradation. Evaluation of mutagenicity by using Salmonella typhimurium test strains, TA98 and TA100 studies revealed that the degradation of crystal violet and malachite green by CM-4 did not lead to mutagenic products. Altogether, these results demonstrated the usefulness of the bacterial consortium in the treatment of the textile dyes. PMID:22623907

  16. Energy consumption in a dye works

    Energy Technology Data Exchange (ETDEWEB)

    Aird, R.J.; Bruffell, P.D.; Wooldridge, D.M.

    1984-06-01

    Basic engineering principles were used to estimate the energy consumption in specific areas of a small dye works. This energy was related to production and heating requirements and this was found to correspond with historical data. The reduction in fuel consumption due to insulation of the steam supply was predicted and the achieved saving was clearly demonstrated using a cumulative sum chart.

  17. Triphenylmethane Dye Activation of Beta-Arrestin

    Science.gov (United States)

    2013-01-01

    β-Arrestins regulate G protein-coupled receptor signaling as competitive inhibitors and protein adaptors. Low molecular weight biased ligands that bind receptors and discriminate between the G protein dependent arm and β-arrestin, clathrin-associated arm of receptor signaling are considered therapeutically valuable as a result of this distinctive pharmacological behavior. Other than receptor agonists, compounds that activate β-arrestins are not available. We show that within minutes of exposure to the cationic triphenylmethane dyes malachite green and brilliant green, tissue culture cells recruit β-arrestins to clathrin scaffolds in a receptor-activation independent manner. In the presence of these compounds, G protein signaling is inhibited, ERK and GSK3β signaling are preserved, and the recruitment of the beta2-adaptin, AP2 adaptor complex to clathrin as well as transferrin internalization is reduced. Moreover, malachite green binds β-arrestin2-GFP coated immunotrap beads relative to GFP only coated beads. Triphenylmethane dyes are FDA approved for topical use on newborns as components of triple-dye preparations and are not approved but used effectively as aqueous antibiotics in fish husbandry. As possible carcinogens, their chronic ingestion in food preparations, particularly through farmed fish, is discouraged in the U.S. and Europe. Our results indicate triphenylmethane dyes as a result of novel pharmacology may have additional roles as β-arrestin/clathrin pathway signaling modulators in both pharmacology research and clinical therapy. PMID:23865508

  18. Optofluidic dye laser in a foil

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Christiansen, Mads Brøkner; Mappes, Timo

    2010-01-01

    First order distributed feedback optofluidic dye lasers embedded in a 350 mu m thick TOPAS (R) foil are demonstrated. They are designed in order to give high output pulse energies. Microfluidic channels and first order distributed feedback gratings are fabricated in parallel by thermal nanoimprint...

  19. Dye-sensitised solar cell (artificial photosynthesis)

    CSIR Research Space (South Africa)

    Le Roux, Lukas J

    2005-07-01

    Full Text Available A novel system that harnesses solar energy is the nano-crystalline TiO dye-sensitised solar cell (DSC), in conjunction with several new concepts, such as nanotechnology and molecular devices. An efficient and low-cost cell can be produced by using...

  20. Expeditious, mechanochemical synthesis of BODIPY dyes

    OpenAIRE

    Laramie P. Jameson; Sergei V. Dzyuba

    2013-01-01

    Summary BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  1. Expeditious, mechanochemical synthesis of BODIPY dyes

    Directory of Open Access Journals (Sweden)

    Laramie P. Jameson

    2013-04-01

    Full Text Available BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  2. Expeditious, mechanochemical synthesis of BODIPY dyes.

    Science.gov (United States)

    Jameson, Laramie P; Dzyuba, Sergei V

    2013-01-01

    BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

  3. Effect of dye extracting solvents and sensitization time on photovoltaic performance of natural dye sensitized solar cells

    Directory of Open Access Journals (Sweden)

    Md. Khalid Hossain

    Full Text Available In this study, natural dye sensitizer based solar cells were successfully fabricated and photovoltaic performance was measured. Sensitizer (turmeric sources, dye extraction process, and photoanode sensitization time of the fabricated cells were analyzed and optimized. Dry turmeric, verdant turmeric, and powder turmeric were used as dye sources. Five distinct types of solvents were used for extraction of natural dye from turmeric. Dyes were characterized by UV–Vis spectrophotometric analysis. The extracted turmeric dye was used as a sensitizer in the dye sensitized solar cell’s (DSSC photoanode assembly. Nano-crystalline TiO2 was used as a film coating semiconductor material of the photoanode. TiO2 films on ITO glass substrate were prepared by simple doctor blade technique. The influence of the different parameters VOC, JSC, power density, FF, and η% on the photovoltaic characteristics of DSSCs was analyzed. The best energy conversion performance was obtained for 2 h adsorption time of dye on TiO2 nano-porous surface with ethanol extracted dye from dry turmeric. Keywords: DSSC, Natural dye, TiO2 photoanode, Dye extracting solvent, Dye-adsorption time

  4. Dye-sensitized solar cell using natural dyes extracted from spinach and ipomoea

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H., E-mail: f10381@ntut.edu.t [Department of Mechanical Engineering, National Taipei University of Technology, No. 1. Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Wu, H.M. [Department of Materials Engineering, Tatung University, No. 40, Sec. 3, Jhongshan N. Rd. Jhongshan District, Taipei City 104, Taiwan (China); Chen, T.L. [Department of Industrial Design, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Huang, K.D. [Department of Vehicle Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Jwo, C.S. [Department of Energy and Air-Conditioning Refrigeration Engineering, National Taipei University of Technology, No. 1, Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China); Lo, Y.J. [Department of Mechanical Engineering, National Taipei University of Technology, No. 1. Sec. 3, Chung-Hsiao E. Rd., Taipei 10608, Taiwan (China)

    2010-04-16

    This study used spinach extract, ipomoea leaf extract and their mixed extracts as the natural dyes for a dye-sensitized solar cell (DSSC). Spinach and ipomoea leaves were first placed separately in ethanol and the chlorophyll of these two kinds of plants was extracted to serve as the natural dyes for using in DSSCs. In addition, the self-developed nanofluid synthesis system prepared a TiO{sub 2} nanofluid with an average particle size of 50 nm. Electrophoresis deposition was performed to let the TiO{sub 2} deposit nanoparticles on the indium tin oxide (ITO) conductive glass, forming a TiO{sub 2} thin film with the thickness of 11.61 {mu}m. This TiO{sub 2} thin film underwent sintering at 450 {sup o}C to enhance the compactness of thin film. Finally, the sintered TiO{sub 2} thin film was immersed in the natural dye solutions extracted from spinach and ipomoea leaves, completing the production of the anode of DSSC. This study then further inspected the fill factor, photoelectric conversion efficiency and incident photon current efficiency of the encapsulated DSSC. According to the experimental results of current-voltage curve, the photoelectric conversion efficiency of the DSSCs prepared by natural dyes from ipomoea leaf extract is 0.318% under extraction temperature of 50 {sup o}C and pH value of extraction fluid at 1.0. This paper also investigated the influence of the temperature in the extraction process of this kind of natural dye and the influence of pH value of the dye solution on the UV-VIS patterns absorption spectra of the prepared natural dye solutions, and the influence of these two factors on the photoelectric conversion efficiency of DSSC.

  5. Pond dyes are Culex mosquito oviposition attractants

    Directory of Open Access Journals (Sweden)

    Natali Ortiz Perea

    2017-05-01

    Full Text Available Background British mosquito population distribution, abundance, species composition and potential for mosquito disease transmission are intimately linked to the physical environment. The presence of ponds and water storage can significantly increase the density of particular mosquito species in the garden. Culex pipiens is the mosquito most commonly found in UK gardens and a potential vector of West Nile Virus WNV, although the current risk of transmission is low. However any factors that significantly change the distribution and population of C. pipiens are likely to impact subsequent risk of disease transmission. Pond dyes are used to control algal growth and improve aesthetics of still water reflecting surrounding planting. However, it is well documented that females of some species of mosquito prefer to lay eggs in dark water and/or containers of different colours and we predict that dyed ponds will be attractive to Culex mosquitoes. Methods Black pond dye was used in oviposition choice tests using wild-caught gravid C. pipiens. Larvae from wild-caught C. pipiens were also reared in the pond dye to determine whether it had any impact on survival. An emergence trap caught any adults that emerged from the water. Water butts (80 L were positioned around university glasshouses and woodland and treated with black pond dye or left undyed. Weekly sampling over a six month period through summer and autumn was performed to quantified numbers of larvae and pupae in each treatment and habitat. Results Gravid female Culex mosquitoes preferred to lay eggs in dyed water. This was highly significant in tests conducted under laboratory conditions and in a semi-field choice test. Despite this, survivorship in black dyed water was significantly reduced compared to undyed water. Seasonal analysis of wild larval and pupal numbers in two habitats with and without dye showed no impact of dye but a significant impact of season and habitat. Mosquitoes were more

  6. Method of dye removal for the textile industry

    Science.gov (United States)

    Stone, Mark L.

    2000-01-01

    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.

  7. Study on decolorization of dyeing wastewater by electrochemical treatment

    Science.gov (United States)

    Chen, Jianjun; Xiaohui, Wang; Hao, Wu; Qi, Jiang

    2018-02-01

    In view of the decolorization of dyeing wastewater, three different kinds of simulated dyeing wastewater were treated by electrochemical method. The effects of current density, initial pH, electrolyte concentration and initial concentration of dye on the treatment effect were investigated, and the decolorization mechanism and color reversion were studied. The experimental results show that the decolorization rate of the three kinds of dyeing wastewater is more than 90% after 60min treatment. And the decolorization process is mainly chromogenic groups gradually destroyed, the dye molecules are gradually degraded. Moreover, in the natural conditions, aeration conditions, heating conditions, almost no phenomenon of color reversion occured.

  8. Re-evaluation of azo dyes as food additives

    DEFF Research Database (Denmark)

    Pratt, Iona; Larsen, John Christian; Mortensen, Alicja

    2013-01-01

    Aryl azo compounds are widely used as colorants (azo dyes) in a wide range of products including textiles, leather, paper, cosmetics, pharmaceuticals and food.As part of its systematic re-evaluation of food additives, the European Food Safety Authority (EFSA) has carried out new risk assessments...... of allazo dyes permitted in food. EFSA has also evaluated a number of azo dyes found illegally in food in recent years, including Sudan dyes, Para Red and Orange II. The re-evaluation of all food colours, including the azo dyes,was considered high priority (i) because colorants were among the first...

  9. Encapsulation of Solitary Dye Molecules in Silica Nanoshells

    Science.gov (United States)

    Levinger, Nancy E.; Langdon, Benjamin

    2000-03-01

    We report on the encapsulation of solitary coumarin 343 dye molecules within hollow silica nanospheres. Through steady-state and time-resolved spectroscopy, we demonstrate that the dye molecule is isolated from bulk solution. The fluorescence lifetime of the dye is dramatically shortened and non-single exponential. Fluorescence quenching shows that the encapsulated dye is unaffected by the presence of the methyl viologen quencher. Time resolved fluorescence anisotropy shows that the encapsulated dye does not move freely as it does in bulk solution. Interpretation of the results will be presented.

  10. Raman Spectroscopic Investigation of Dyes in Spices

    Science.gov (United States)

    Uhlemann, Ute; Ramoji, Anuradha; Rösch, Petra; Da Costa Filho, Paulo Augusto; Robert, Fabien; Popp, Jürgen

    2010-08-01

    In this study, a number of synthetic colorants for spices have been investigated by means of Raman spectroscopy, resonance Raman spectroscopy, and surface enhanced (resonance) Raman spectroscopy (SER(S)). The aim of the study was the determination of limits of detection for each dye separately and in binary mixtures of dyes in spiked samples of the spices. Most of the investigated dyes have been azo dyes, some being water-soluble, the other being fat-soluble. Investigating the composition of food preparations is an ongoing and important branch of analytical sciences. On one hand, new ingredients have to be analyzed with regard to their contents, on the other hand, raw materials that have been tampered have to be eliminated from food production processes. In the last decades, the various Raman spectroscopic methods have proven to be successful in many areas of life and materials sciences. The ability of Raman spectroscopy to distinguish even structural very similar analytes by means of their vibrational fingerprint will also be important in this study. Nevertheless, Raman scattering is a very weak process that is oftentimes overlaid by matrix interferences or fluorescence. In order to achieve limits of detection in the nanomolar range, the signal intensity has to be increased. According to the well-known equations, there are several ways of achieving this increase: •increasing sample concentration •increasing laser power •decreasing the laser wavelength •using electronic resonance •increasing the local electromagnetic field In this study, nearly all of the above-mentioned principles were applied. In a first step, all dyes were investigated in solution at different concentrations to determine a limit of detection. In the second step, spiked spice samples have been extracted with a variety of solvents and process parameters tested. To lower the limit of detection even further, SERS spectroscopy has been used as well in as out of electronic resonance.

  11. Improving the Spectral Response of Black Dye by Cosensitization with a Simple Indoline Based Dye in Dye-Sensitized Solar Cell

    Directory of Open Access Journals (Sweden)

    Md. Akhtaruzzaman

    2013-01-01

    Full Text Available Indoline dye D-1 was successfully applied as a cosensitizer for improving the spectral response of black dye in dye-sensitized solar cells (DSCs. It was observed that D-1 effectively increases the short-circuit photocurrent by offsetting the competitive light absorption by I/I3- electrolyte in the wavelength region 350–500 nm when adsorbed on the TiO2 nanocrystaline films in a mix dye system. The DSCs containing the D-1 and black dye achieved a power conversion efficiency of 9.80% with higher short-circuit photocurrent of 19.54 mA/cm2 compared to the system of black dye without cosensitization under standard AM 1.5 sunlight.

  12. Chemical Modification on Reactive Dye Adsorption Capacity of Castor Seeds

    Directory of Open Access Journals (Sweden)

    V. Dharmalingam

    2011-01-01

    Full Text Available Abstract: The roles played by four major functional groups (amine, carboxyl, azo, hydroxyl groups in the biomass of castor seeds in adsorption of seven dyes were investigated. These functional groups in castor seeds were chemically modified individually to determine their contribution to the adsorption of ionic dyes. The dyes used were remazol red B, procino yellow, fast green FCF, brilliant cresyl blue, methylene blue, neutral red, red-141. It was found that hydroxyl group inhibited the adsorption of anionic dyes but it was major functional group in the adsorption of cationic dyes, hydroxyl group was important functional group in the adsorption of all seven dyes and the effect of methylation of amino group was not significant on the adsorption of seven dyes.

  13. Investigation of dye functional group on the photocatalytic degradation of dyes by nano-TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Vinu, R.; Akki, Spurti U. [Department of Chemical Engineering, Indian Institute Of Science, Bangalore, 560012, Karnataka (India); Madras, Giridhar, E-mail: giridhar@chemeng.iisc.ernet.in [Department of Chemical Engineering, Indian Institute Of Science, Bangalore, 560012, Karnataka (India)

    2010-04-15

    The photocatalytic degradation of five anionic, eight cationic and three solvent dyes using combustion-synthesized nano-TiO{sub 2} (CS TiO{sub 2}) and commercial Degussa P-25 TiO{sub 2} (DP-25) were evaluated to determine the effect of the functional group in the dye. The degradation of the dyes was quantified using the initial rate of decolorization and mineralization. The decolorization of the anionic dyes with CS TiO{sub 2} followed the order: indigo carmine > eosin Y > amido black 10B > alizarin cyanine green > orange G. The decolorization of the cationic dyes with DP-25 followed the order: malachite green > pyronin Y > rhodamine 6G > azure B > nile blue sulfate > auramine O {approx} acriflavine {approx} safranin O. CS TiO{sub 2} showed higher rates of decolorization and mineralization for all the anionic dyes compared to DP-25, while DP-25 was better in terms of decolorization for most of the cationic dyes. The solvent dyes exhibited adsorption dependent decolorization. The order of decolorization and mineralization of the anionic and cationic dyes (a) with CS TiO{sub 2} and DP-25 was different and correlated with the surface properties of these catalysts (b) were rationalized with the molecular structure of the dye and the degradation pathway of the dye.

  14. Investigation of dye functional group on the photocatalytic degradation of dyes by nano-TiO2.

    Science.gov (United States)

    Vinu, R; Akki, Spurti U; Madras, Giridhar

    2010-04-15

    The photocatalytic degradation of five anionic, eight cationic and three solvent dyes using combustion-synthesized nano-TiO(2) (CS TiO(2)) and commercial Degussa P-25 TiO(2) (DP-25) were evaluated to determine the effect of the functional group in the dye. The degradation of the dyes was quantified using the initial rate of decolorization and mineralization. The decolorization of the anionic dyes with CS TiO(2) followed the order: indigo carmine > eosin Y > amido black 10B > alizarin cyanine green > orange G. The decolorization of the cationic dyes with DP-25 followed the order: malachite green > pyronin Y > rhodamine 6G > azure B > nile blue sulfate > auramine O approximately = acriflavine approximately = safranin O. CS TiO(2) showed higher rates of decolorization and mineralization for all the anionic dyes compared to DP-25, while DP-25 was better in terms of decolorization for most of the cationic dyes. The solvent dyes exhibited adsorption dependent decolorization. The order of decolorization and mineralization of the anionic and cationic dyes (a) with CS TiO(2) and DP-25 was different and correlated with the surface properties of these catalysts (b) were rationalized with the molecular structure of the dye and the degradation pathway of the dye. 2009 Elsevier B.V. All rights reserved.

  15. Towards Rational Designing of Efficient Sensitizers Based on Thiophene and Infrared Dyes for Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Ahmad Irfan

    2014-01-01

    Full Text Available Geometries, electronic properties, and absorption spectra of the dyes which are a combination of thiophene based dye (THPD and IR dyes (covering IR region; TIRBD1-TIRBD3 were performed using density functional theory (DFT and time dependent density functional theory (TD-DFT, respectively. Different electron donating groups, electron withdrawing groups, and IR dyes have been substituted on THPD to enhance the efficiency. The bond lengths of new designed dyes are almost the same. The lowest unoccupied molecular orbital energies of designed dyes are above the conduction band of TiO2 and the highest occupied molecular orbital energies are below the redox couple revealing that TIRBD1-TIRBD3 would be better sensitizers for dye-sensitized solar cells. The broad spectra and low energy gap also showed that designed materials would be efficient sensitizers.

  16. Synthesis and dyeing performance of bisazo disperse dyes based on 3-[4-(4-amino-2-chlorophenoxyanilino]phenol

    Directory of Open Access Journals (Sweden)

    Rajesh H. Parab

    2016-09-01

    Full Text Available The present communication aims to develop bisazo disperse dyes based on 3-[4-(4-amino-2-chlorophenoxyanilino]phenol (DAP both as a coupling component as well as a diazonium salt. Coupling reaction of DAP was carried out with a diazonium salt of 4-aminoacetanilide to yield a monoazo disperse dye, and then it was further used as a diazonium salt and coupled with a different aromatic phenol to synthesize bisazo disperse dyes. All the disperse dyes were characterized by elemental analysis, IR, NMR and UV–Visible spectral studies with a view to determine their chemical structure. The dyeing ability of these bisazo disperse dyes has been evaluated in terms of their dyeing behavior and fastness properties on different fabrics.

  17. Use of the ultrasonic cavitation in wool dyeing process: Effect of the dye-bath temperature.

    Science.gov (United States)

    Actis Grande, G; Giansetti, M; Pezzin, A; Rovero, G; Sicardi, S

    2017-03-01

    The present work aims to study the effect of the liquid temperature on the performance of ultrasounds (US) in a dyeing process. The approach was both theoretical and experimental. In the theoretical part the simplified model of a single bubble implosion is used to demonstrate that the "maximum implosion pressure" calculated with the well known Rayleigh-Plesset equation for a single bubble can be correlated with the cavitation intensity experimentally measured with an Ultrasonic Energy Meter (by PPB Megasonics). In particular the model was used to study the influence of the fluid temperature on the cavitation intensity. The "relative" theoretical data calculated from the implosion pressure were satisfactorily correlated with the experimental ones and evidence a zone, between 50 and 60°C, were the cavitation intensity is almost constant and still sufficiently high. Hence an experimental part of wool dyeing was carried out both to validate the previous results and to verify the dyeing quality at low temperatures (40-70°C) in presence of US. A prototype dyeing equipment able to treat textile samples with US system of 600W power, was used. The dyeing performances in the presence and absence of US were verified by measuring ΔE (colour variation), R e,% (reflectance percentage), K/S (colour strength) and colour fastness. The US tests performed in the temperature range of 40-70°C were compared with the conventional wool dyeing at 98°C. The obtained results show that a temperature close to 60°C should be chosen as the recommended US dyeing condition, being a compromise between the cavitation intensity and the kinetics which rules the dyestuff diffusion within the fibres. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Novel diyne-bridged dyes for efficient dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Jing-Kun, E-mail: fjk@njust.edu.cn [Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei Street No. 200, Nanjing, 210094 (China); Sun, Tengxiao [Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei Street No. 200, Nanjing, 210094 (China); Tian, Yi [Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577 (Japan); Zhang, Yingjun, E-mail: ZhangYingjun@hec.cn [HEC Pharm Group, HEC R& D Center, Dongguan, 523871 (China); Jin, Chuanfei [HEC Pharm Group, HEC R& D Center, Dongguan, 523871 (China); Xu, Zhimin; Fang, Yu; Hu, Xiangyu; Wang, Haobin [Department of Chemistry, School of Chemical Engineering, Nanjing University of Science and Technology, Xiaolingwei Street No. 200, Nanjing, 210094 (China)

    2017-07-01

    Three new metal free organic dyes (FSD101-103) were synthesized to investigate the influence of diyne unit on dye molecules. FSD101 and FSD102 with diyne unit and FSD103 with monoyne unit were applied as sensitizers in the dye-sensitized solar cells (DSSCs). The optical and electrochemical properties, theoretical studies, and photovoltaic parameters of DSSCs sensitized by these dyes were systematically investigated. By replacing the monoyne unit with a diyne unit, FSD101 exhibited broader absorption spectrum, lower IP, higher EA, lower band gap energy, higher oscillator strength, more efficient electron injection ability, broader IPCE response range and higher τ{sub e} in comparison with FSD103. Hence, DSSC sensitized by FSD101 showed higher J{sub sc} and V{sub oc} values, and demonstrated a power conversion efficiency of 3.12%, about 2-fold as that of FSD103 (1.55%). FSD102 showed similar results as FSD101, with a power conversion efficiency of 2.98%, despite a stronger electron withdraw cyanoacrylic acid group was introduced. This may be due to the lower efficiency of the electron injection from dye to TiO{sub 2} and lower τ{sub e} of FSD102 than that of FSD101. These results indicate that the performance of DSSCs can be significantly improved by introducing a diyne unit into this type of organic dyes. - Highlights: • Diyne-bridge was introduced into dye molecules by a transition-metal-free protocol. • Power conversion efficiency grows from 1.55% to 3.12% by replacing monoyne unit with diyne unit. • FSD101 with diyne unit shows the highest electron lifetime resulting in a higher V{sub oc}.

  19. Detoxification of azo dyes in the context of environmental processes.

    Science.gov (United States)

    Rawat, Deepak; Mishra, Vandana; Sharma, Radhey Shyam

    2016-07-01

    Azo dyes account for >70% of the global industrial demand (∼9 million tons). Owing to their genotoxic/carcinogenic potential, the annual disposal of ∼4,500,000 tons of dyes and/or degraded products is an environmental and socio-economic concern. In comparison to physico-chemical methods, microbe-mediated dye degradation is considered to be low-input, cost-effective and environmentally-safe. However, under different environmental conditions, interactions of chemically diverse dyes with metabolically diverse microbes produce metabolites of varying toxicity. In addition, majority of studies on microbial dye-degradation focus on decolorization with least attention towards detoxification. Therefore, the environmental significance of microbial dye detoxification research of past >3 decades is critically evaluated with reference to dye structure and the possible influence of microbial interactions in different environments. In the absence of ecosystem-based studies, the results of laboratory-based studies on dye degradation, metabolite production and their genotoxic impact on model organisms are used to predict the possible fate and consequences of azo dyes/metabolites in the environment. In such studies, the predominance of fewer numbers of toxicological assays that too at lower levels of biological organization (molecular/cellular/organismic) suggests its limited ecological significance. Based on critical evaluation of these studies the recommendations on inclusion of multilevel approach (assessment at multiple levels of biological organization), multispecies microcosm approach and native species approach in conjunction with identification of dye metabolites have been made for future studies. Such studies will bridge the gap between the fundamental knowledge on dye-microbe-environment interactions and its application to combat dye-induced environmental toxicity. Thus an environmental perspective on dye toxicity in the background of dye structure and effects of

  20. Dye-sensitized nanocrystalline TiO{sub 2} solar cells based on novel coumarin dyes

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Kohjiro; Tachibana, Yasuhiro; Sayama, Kazuhiro; Sugihara, Hideki; Arakawa, Hironori [National Inst. of Advanced Industrial Science and Technology, Ibaraki (Japan). Photoreaction Control Research Center; Ohga, Yasuyo; Shinpo, Akira; Suga, Sadaharu [Hayashibara Biochemical Labs., Okayama (Japan)

    2003-04-30

    We have developed dye-sensitized nanocrystalline TiO{sub 2} solar cells (DSSCs) based on novel coumarin-dye photosensitizers. The absorption spectra of these novel dyes are red-shifted remarkably in the visible region relative to the spectrum of C343, a conventional coumarin dye. Introduction of a methine unit (-CH=CH-) connecting the cyano (-CN) and carboxyl (-COOH) groups into the coumarin framework expanded the {pi}-conjugation in the dye and thus resulted in a wide absorption in the visible region. These novel dyes performed as efficient photosensitizers for DSSCs. A DSSC based on 2-cyano-5-(1,1,6,6-tetramethyl-10-oxo-2,3,5,6-tetrahydro-1H,4H,10H-11-oxa-3a-a= za-benzo[de]anthracen-9-yl)-penta-2,4-dienoic acid (NKX-2311), produced a 6.0% solar energy-to-electricity conversion efficiency ({eta}), the highest performance among DSSCs based on organic-dye photosensitizers, under AM 1.5 irradiation (100 mW cm{sup -2}) with a short-circuit current density (J{sub sc}) of 14.0 mA cm{sup -2}, an open-circuit voltage (V{sub oc}) of 0.60 V, and a fill factor of 0.71. Our results suggests that the structure of NKX-2311 whose carboxyl group is directly connected to the -CH=CH- unit, is advantageous for effective electron injection from the dye into the conduction band of TiO{sub 2}. In addition, the cyano group, owing to its strong electron-withdrawing ability, might play an important role in electron injection in addition to a red shift in the absorption region. On a long-term stability test under continuous irradiation with white light (80 mW cm{sup -2}), stable performance was attained with a solar cell based on the NKX-2311 dye with a turnover number of 2.6x10{sup 7} per one molecule. (Author)

  1. Dye-sensitized nanocrystalline TiO{sup 2} solar cells based on novel coumarin dyes

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Kohjiro; Tachibana, Yasuhiro; Sayama, Kazuhiro; Sugihara, Hideki; Arakawa, Hironori [Photoreaction Control Research Center (PCRC) Science and Technology, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Ohga, Yasuyo; Shinpo, Akira; Suga, Sadaharu [Hayashibara Biochemical Laboratories, Inc., 564-176 Fujita, Okayama 701-0221 (Japan)

    2003-04-30

    We have developed dye-sensitized nanocrystalline TiO{sub 2} solar cells (DSSCs) based on novel coumarin-dye photosensitizers. The absorption spectra of these novel dyes are red-shifted remarkably in the visible region relative to the spectrum of C343, a conventional coumarin dye. Introduction of a methine unit (-CH==CH-) connecting the cyano (-CN) and carboxyl (-COOH) groups into the coumarin framework expanded the {pi}-conjugation in the dye and thus resulted in a wide absorption in the visible region. These novel dyes performed as efficient photosensitizers for DSSCs. A DSSC based on 2-cyano-5-(1,1,6,6-tetramethyl-10-oxo-2,3,5,6-tetrahydro-1H,4H,10H-11-oxa-3a- aza-benzo[de]anthracen-9-yl)-penta-2,4-dienoic acid (NKX-2311), produced a 6.0% solar energy-to-electricity conversion efficiency ({eta}), the highest performance among DSSCs based on organic-dye photosensitizers, under AM 1.5 irradiation (100mWcm{sup -2}) with a short-circuit current density (J{sub sc}) of 14.0mAcm{sup -2}, an open-circuit voltage (V{sub oc}) of 0.60V, and a fill factor of 0.71. Our results suggests that the structure of NKX-2311 whose carboxyl group is directly connected to the -CH==CH- unit, is advantageous for effective electron injection from the dye into the conduction band of TiO{sub 2}. In addition, the cyano group, owing to its strong electron-withdrawing ability, might play an important role in electron injection in addition to a red shift in the absorption region. On a long-term stability test under continuous irradiation with white light (80mWcm{sup -2}), stable performance was attained with a solar cell based on the NKX-2311 dye with a turnover number of 2.6x10{sup 7} per one molecule.

  2. Nanoimprinted polymer photonic crystal dye lasers

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Smith, Cameron; Buss, Thomas

    2010-01-01

    Optically pumped polymer photonic crystal band-edge dye lasers are presented. The photonic crystal is a rectangular lattice providing laser feedback as well as an optical resonance for the pump light. The lasers are defined in a thin film of photodefinable Ormocore hybrid polymer, doped...... with the laser dye Pyrromethene 597. A compact frequency doubled Nd:YAG laser (352 nm, 5 ns pulses) is used to pump the lasers from above the chip. The laser devices are 450 nm thick slab waveguides with a rectangular lattice of 100 nm deep air holes imprinted into the surface. The 2-dimensional rectangular...... lattice is described by two orthogonal unit vectors of length a and b, defining the P and X directions. The frequency of the laser can be tuned via the lattice constant a (187 nm - 215 nm) while pump light is resonantly coupled into the laser from an angle () depending on the lattice constant b (355 nm...

  3. Yellow Dye Extraction from Eucalyptus Grandis Bark.

    OpenAIRE

    Chengeto Zvavamwe; Cathrine Khetiwe Mkandhla; Clever Mpofu; Vernon Phiri; Felicity Bgwoni; Bettina Khonzokuhle Ncube; Mafika Sibutha; Joel Tshuma

    2016-01-01

    In this article, yellow dye was extracted from Eucalyptus Grandis bark using methanol solvent at a temperature of 250C and pressure of 1 atmosphere. The extraction process was optimized by varying extraction material-to-liquor ratio, in the ratios of 1:100, 1:50, 3:100, 1:25, 1:20, 3:50, 7:100, 2:25, 9:100 and 1:10. The extraction pH was varied from 1 to 13 at an interval of pH 1. The mass of the dye extract was found to be directly proportional to the mass of the bark at each pH. The optimum...

  4. Solvatochromic dyes detect the presence of homeopathic potencies.

    Science.gov (United States)

    Cartwright, Steven J

    2016-02-01

    A systematic approach to the design of simple, chemical systems for investigating the nature of homeopathic medicines has led to the development of an experimental protocol in which solvatochromic dyes are used as molecular probes of serially diluted and agitated solutions. Electronic spectroscopy has been used to follow changes in the absorbance of this class of dyes across the visible spectrum in the presence of homeopathic potencies. Evidence is presented using six different solvatochromic dyes in three different solvent systems. In all cases homeopathic potencies produce consistent and reproducible changes in the spectra of the dyes. Results suggest that potencies influence the supramolecular chemistry of solvatochromic dyes, enhancing either dye aggregation or disaggregation, depending upon dye structure. Comparable dyes lacking the intramolecular charge transfer feature of solvatochromic dyes are unaffected by homeopathic potencies, suggesting potencies require the oscillating dipole of solvatochromic dyes for effective interaction. The implications of the results presented, both for an eventual understanding of the nature of homeopathic medicines and their mode of action, together with future directions for research in this area, are discussed. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  5. Knowledge, attitude, and practice of dyeing and printing workers

    Directory of Open Access Journals (Sweden)

    Paramasivam Parimalam

    2010-01-01

    Full Text Available Background: Millions of workers are occupationally exposed to dyes in the world, but little is known about their knowledge and attitudes toward the effects of dye on their health. Objectives: The aim of this study was to assess the fabric dyers′ and fabric printers′ knowledge, attitude, and practice toward the health hazard of dyes. Materials and Methods: The present study was taken up in the Madurai district which is situated in the Southern Tamil Nadu, India. One hundred and forty-two workers employed in small-scale dyeing and printing units participated in a face-to-face confidential interview . Results: The mean age of fabric dyers and fabric printers was 42 years (΁10.7. When enquired about whether dyes affect body organ(s, all the workers agreed that dye(s will affect skin, but they were not aware that dyes could affect other parts of the body. All the workers believed that safe methods of handling of dyes and disposal of contaminated packaging used for dyes need to be considered. It was found that 34% of the workers were using personal protective equipment (PPE such as rubber hand gloves during work. Conclusion: The workers had knowledge regarding the occupational hazards, and their attitudinal approach toward the betterment of the work environment is positive.

  6. Knowledge, attitude, and practice of dyeing and printing workers.

    Science.gov (United States)

    Paramasivam, Parimalam; Raghavan, Premalatha Mundankandath; Srinivasan, Padmini Dasu; Kumar, Ganguli Anindya

    2010-10-01

    Millions of workers are occupationally exposed to dyes in the world, but little is known about their knowledge and attitudes toward the effects of dye on their health.. The aim of this study was to assess the fabric dyers' and fabric printers' knowledge, attitude, and practice toward the health hazard of dyes. The present study was taken up in the Madurai district which is situated in the Southern Tamil Nadu, India. One hundred and forty-two workers employed in small-scale dyeing and printing units participated in a face-to-face confidential interview. The mean age of fabric dyers and fabric printers was 42 years (±10.7). When enquired about whether dyes affect body organ(s), all the workers agreed that dye(s) will affect skin, but they were not aware that dyes could affect other parts of the body. All the workers believed that safe methods of handling of dyes and disposal of contaminated packaging used for dyes need to be considered. It was found that 34% of the workers were using personal protective equipment (PPE) such as rubber hand gloves during work. The workers had knowledge regarding the occupational hazards, and their attitudinal approach toward the betterment of the work environment is positive.

  7. The pattern of hair dyeing in koreans with gray hair.

    Science.gov (United States)

    Jo, Seong Jin; Shin, Hyoseung; Paik, Seung Hwan; Choi, Jae Woo; Lee, Jong Hee; Cho, Soyun; Kwon, Ohsang

    2013-11-01

    Hair graying is considered as a part of normal ageing process. Nonetheless, this process raises a significant cosmetic concern, especially among ethnic Korean elderly whose baseline hair color is black. For this reason, Korean elderly dye their hair with frequency despite the risk of dermatologic problems such as allergic contact dermatitis. In this study, the authors investigate the prevalence and pattern of hair dyeing and its relation with scalp diseases in Korea. Six hundred twenty subjects (330 men and 290 women) with graying hair were given a questionnaire survery and underwent a physical examination. Of the 620 total, 272 subjects (43.9%) dyed their hair. Hair dyeing was significantly more frequent among women than among men (phair dyeing when compared to either younger or older groups. Subjective self-assessment of the extent of hair graying was associated with increased prevalence of hair dyeing, that is, individuals who feel graying has advanced by more than 20% of the overall hair were much more likely to dye their hair (pHair dyeing did not correlate with either alopecia or scalp disease. Our survey has found that the prevalence of hair dyeing is higher among Korean women than men. People in their fifties and sixties and people with more than 20% extent of grayness were more likely to dye their hair than otherwise. Hair dyeing was not associated with any increase in the prevalence of scalp diseases.

  8. Degradation of azo dyes by environmental microorganisms and helminths

    Energy Technology Data Exchange (ETDEWEB)

    Kingthom Chung; Stevens, S.E. Jr. (Memphis State Univ., TN (United States). Dept. of Biology)

    1993-11-01

    The degradation of azo dyes by environmental microorganisms, fungi, and helminths is reviewed. Azo dyes are used in a wide variety of products and can be found in the effluent of most sewage treatment facilities. Substantial quantities of these dyes have been deposited in the environment, particularly in streams and rivers. Azo dyes were shown to affect microbial activities and microbial population sizes in the sediments and in the water columns of aquatic habitats. Only a few aerobic bacteria have been found to reduce azo dyes under aerobic conditions, and little is known about the process. A substantial number of anaerobic bacteria capable of azo dye reduction have been reported. The enzyme responsible for azo dye reduction has been partially purified, and characterization of the enzyme is proceeding. The nematode Ascaris lumbricoides and the cestode Moniezia expanza have been reported to reduce azo dyes anaerobically. Recently the fungus Phanerochaete chrysoporium was reported to mineralize azo dyes via a peroxidation-mediated pathway. A possible degradation pathway for the mineralization of azo dye is proposed and future research needs are discussed.

  9. Novel conjugated organic dyes for efficient dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hara, K.; Sato, T.; Katoh, R.; Furube, A.; Yoshihara, T.; Murai, M.; Kurashige, M.; Arakawa, H. [National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Ito, S.; Shinpo, A.; Suga, S. [Hayashibara Biochemical Laboratories, Inc., 564-176 Fujita, Okayama 701-0221 (Japan)

    2005-02-01

    Novel conjugated organic dyes that have N,N-dimethylaniline (DMA) moieties as the electron donor and a cyanoacetic acid (CAA) moiety as the electron acceptor were developed for use in dye-sensitized nanocrystalline-TiO{sub 2} solar cells (DSSCs). We attained a maximum solar-energy-to-electricity conversion efficiency ({eta}) of 6.8 % under AM 1.5 irradiation (100 mW cm{sup -2}) with a DSSC based on 2-cyano-7,7-bis(4-dimethylamino-phenyl)hepta-2,4,6-trienoic acid (NKX-2569): short-circuit photocurrent density (J{sub sc}) = 12.9 mA cm{sup -2}, open-circuit voltage (V{sub oc}) = 0.71 V, and fill factor (ff) = 0.74. The high performance of the solar cells indicated that highly efficient electron injection from the excited dyes to the conduction band of TiO{sub 2} occurred. The experimental and calculated Fourier-transform infrared (FT-IR) absorption spectra clearly showed that these dyes were adsorbed on the TiO{sub 2} surface with the carboxylate coordination form. A molecular-orbital calculation indicated that the electron distribution moved from the DMA moiety to the CAA moiety by photoexcitation of the dye. (Abstract Copyright [2005], Wiley Periodicals, Inc.)

  10. Comparative Testis Tissue Proteomics Using 2-Dye Versus 3-Dye DIGE Analysis.

    Science.gov (United States)

    Holland, Ashling

    2018-01-01

    Comparative tissue proteomics aims to analyze alterations of the proteome in response to a stimulus. Two-dimensional difference gel electrophoresis (2D-DIGE) is a modified and advanced form of 2D gel electrophoresis. DIGE is a powerful biochemical method that compares two or three protein samples on the same analytical gel, and can be used to establish differentially expressed protein levels between healthy normal and diseased pathological tissue sample groups. Minimal DIGE labeling can be used via a 2-dye system with Cy3 and Cy5 or a 3-dye system with Cy2, Cy3, and Cy5 to fluorescently label samples with CyDye flours pre-electrophoresis. DIGE circumvents gel-to-gel variability by multiplexing samples to a single gel and through the use of a pooled internal standard for normalization. This form of quantitative high-resolution proteomics facilitates the comparative analysis and evaluation of tissue protein compositions. Comparing tissue groups under different conditions is crucially important for advancing the biomedical field by characterization of cellular processes, understanding pathophysiological development and tissue biomarker discovery. This chapter discusses 2D-DIGE as a comparative tissue proteomic technique and describes in detail the experimental steps required for comparative proteomic analysis employing both options of 2-dye and 3-dye DIGE minimal labeling.

  11. Comparing the mode of action of intraocular lutein-based dyes with synthetic dyes.

    Science.gov (United States)

    Sousa-Martins, Diogo; Caseli, Luciano; Figueiredo, Mafalda C; Sa E Cunha, Claudia; Mota-Filipe, Helder; Souza-Lima, Acácio; Belfort, Rubens; Rodrigues, Eduardo; Maia, Mauricio

    2015-02-19

    To investigate and compare the mechanism by which lutein-based and synthetic intraocular dyes interact with their target membranes during ophthalmic surgeries. Surrogate membrane models were used in order to simulate the different intraocular membranes: internal limiting membrane (ILM), vitreous, anterior capsule (AC), and epiretinal membrane (ERM). Different lutein-based dyes, such as Phacodyne, Retidyne, Retidyne Plus, and Vitreodyne were tested, as well as Trypan Blue (TB), Indocyanine Green (ICG), Brilliant Blue (BB), and Triamcinolone Acetonide (TA). The interactions between the film components occurring at the air-water interface were investigated with surface pressure-area isotherms and polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS). With the exception of TA and ICG, none of the tested dyes revealed toxicity to the analyzed membranes. The interaction of TA with the vitreous model affected deeply the biointerface structure of the model. A significant condensation of the monolayer is noted when ICG contacted with ILM by the isotherms or even a solubilization of part of the monolayer toward the aqueous subphase. Retidyne Plus may provide the fluidization of the membrane, but maintains intact the structure of proteins present in the model. The present study demonstrates for the first time that lutein-based dyes interact through a physical mechanism of action with membrane models of structures present in human eye. On the other hand, the chemical interaction of synthetic dyes TA and ICG resulted in an alteration of the membrane models. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  12. Treatment of Direct Blending Dye Wastewater and Recycling of Dye Sludge

    Directory of Open Access Journals (Sweden)

    Ming-Li Li

    2012-03-01

    Full Text Available A new sorbent material, barium sulfate-Direct Blending Yellow D-3RNL hybrid (BSD, was synthesized and characterized by various methods. Both the anionic dyes, Reactive Brilliant Red X-3B and Weak Acid Green GS were hardly adsorbed by the BSD material, while the sorption of Ethyl Violet (EV and Victoria Blue B were extremely obvious. The sorption of cationic dyes obeyed the Langmuir isotherm model, which depended on the electric charge attraction. The saturation amount of EV adsorbed onto the BSD material approached to 39.36 mg/g. The sorption of EV changed little with pH from 3 to 12 while it increased with increasing levels of electrolyte. A dye wastewater sampled from Jinjiang Chemicals was treated, and the color removal rate was more than the COD removal rate. In addition, the cationic dye-BSD sludge was utilized as a colorant fill-in coating. The light stability and thermal stability of the colorant was measured and exhibited good features. This work provided a simple and eco-friendly method for dye wastewater treatment with recycling of waste.

  13. Effects of reduction products of ortho-hydroxyl substituted azo dyes on biodecolorization of azo dyes

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guangfei [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Wang Jing, E-mail: wangjingbio@yahoo.cn [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Lu Hong; Jin Ruofei; Zhou Jiti; Zhang Long [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China)

    2009-11-15

    The mediated effects of reduction products of some ortho-hydroxyl substituted azo dyes on biodecolorization were investigated. The results indicated that the addition of reduction products could effectively accelerate dye decolorization by Shigella sp. QRZ-1. The best accelerating effect was obtained with the addition of reduction products of Acid Red 14 (AR14), resulting in an over 3-fold increase in decolorization efficiency of many azo dyes. In sequencing batch reactor experiments, the accelerating effect of reduction products of AR14 was more obvious (1.5-fold) during the startup of the system. When the dye concentration was increased to 500 mg L{sup -1}, the accelerated decolorization efficiency was still maintained around 95%. The presence of AR14 in the feed enhanced the decolorization performance of anaerobic sludge, indicating that the strategy may be beneficial for practical application. 1-Naphthol-2-amino-4-sulfonic acid, which is one of the reduction products of AR14, may function as redox mediator to speed up azo dye biodecolorization.

  14. Time dependent – density functional theory characterization of organic dyes for dye-sensitized solar cells

    KAUST Repository

    Hilal, Rifaat

    2017-06-19

    We aim at providing better insight into the parameters that govern the intramolecular charge transfer (ICT) and photo-injection processes in dyes for dye-sensitised solar cells (DSSC). Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations are utilized to study the geometry, electronic structure, electrostatic potential (ESP) and absorption spectrum, for a representative donor-π bridge-acceptor (D–π–A) dye for DSSC. The coplanar geometry of the dye (D1) facilitates strong conjugation and considerable delocalization originating the π CT interaction from donor to acceptor orbitals and the hyper-conjugative interactions involving Rydberg states. A model simulating the adsorption of the dye on the TiO surface is utilized to estimate binding energies. The effect of fluorine substituents in the π-spacer on the quantum efficiency of DSSCs was investigated. Gibb’s free energy values, redox potentials, excited state lifetime, non-linear optical properties (NLO) and driving forces for D1 and its fluorinated derivatives were computed.

  15. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saltan, Gözde Murat [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Dinçalp, Haluk, E-mail: haluk.dincalp@cbu.edu.tr [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Kıran, Merve; Zafer, Ceylan [Solar Energy Institute, Ege University, Bornova, 35100 Izmir (Turkey); Erbaş, Seçil Çelik [Celal Bayar University, Materials Engineering Department, Faculty of Engineering, Yunus Emre, 45140 Manisa (Turkey)

    2015-08-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO{sub 2}-coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation.

  16. Plasmonic Dye-Sensitized Solar Cells

    KAUST Repository

    Ding, I-Kang

    2010-12-14

    This image presents a scanning electron microscopy image of solid state dye-sensitized solar cell with a plasmonic back reflector, overlaid with simulated field intensity plots when monochromatic light is incident on the device. Plasmonic back reflectors, which consist of 2D arrays of silver nanodomes, can enhance absorption through excitation of plasmonic modes and increased light scattering, as reported by Michael D. McGehee, Yi Cui, and co-workers.

  17. SUITABLE MORDANTS FOR DYEING POSIDONIA OCEANICA FIBERS

    Directory of Open Access Journals (Sweden)

    ROMÁN Silvia

    2017-05-01

    Full Text Available Posidonia oceanica is the most extended sea grass in the Mediterranean Sea. Important quantities of this alga are accumulated on coasts making necessary the cleaninness of those beaches where it can be found. For this reason, many authors are developmenting new products made by this raw material, like green composites or are studing this material to be used as biomass, for example. The aim of this study is to dye the Posidonia Oceanica fiber using commercial natural dye to change their appearance to get a material more attractive for different areas. To achieve this aim, fibers were scoured and bleached in order to remove the brown colour of the Posidonia Oceanica fibers. Scoured and bleached processes were followed by the treatment done for cellulosic fibers, because some researches indicate that P. Oceanica is composed of high quantity of cellulose. Different types of biomordants were use in the pre-treatment of the fiber to improve the affinity between the fiber and the dye used. To compare the results, we evaluate the colour of each sample using CIELAB parameters and colour differences (ΔE*, which are obtained by reflexion spectrophotometre. The results showed that medium molecular weight chitosan, which was used as biomordant, gets the highest intensity of colour

  18. Plastic encapsulated, dye sensitised photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Potter, R.J.; Otley, L.C.; Durrant, J.R.; Haque, S.; Xu, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom); Holmes, A.B.; Park, T.; Schulte, N. [Cambridge Univ. (United Kingdom)

    2004-07-01

    The report presents the results of a collaborative project that aimed to demonstrate the technical feasibility of a plastic-encapsulated, solid state, dye-sensitised solar cell (DSSC) with an energy conversion efficiency (ECE) of at least 3%. DSSCs offer a possible 'step change' in photovoltaic technology resulting in lower costs compared with existing technologies. The project involved a series of eight main tasks: the development of first and second generation HTM electrolytes; the development of polymer-supported electrolytes; the development of low temperature electrode coating procedures; dye development; cell assembly and testing; component integration; and overall process development. A wide range of innovative HTMs have been synthesised, including materials incorporating both hole-transporting and ion-chelating functional groups. The ruthenium-based dye, N3, remained the preferred sensitising component. The project has produced a system that can routinely achieve over 5% ECE at 0.1 Sun illumination on 1 cm{sup 2} cells using polymer-supported electrolytes.

  19. Patent blue dye in lymphaticovenular anastomosis.

    Science.gov (United States)

    Yap, Yan Lin; Lim, Jane; Shim, Timothy W H; Naidu, Shenthilkumar; Ong, Wei Chen; Lim, Thiam Chye

    2009-08-01

    Lymphaticovenular anastomosis (LVA) has been described as a treatment of chronic lymphoedema. This microsurgical technique is new and technically difficult. The small caliber and thin wall lymphatic vessels are difficult to identify and easily destroyed during the dissection. We describe a technique of performing lymphaticovenular anastomosis with patent blue dye enhancement. Our patient is a 50-year-old lady who suffers from chronic lymphoedema of the upper limb after mastectomy and axillary clearance for breast cancer 8 years ago. Patent blue dye is injected subdermally and is taken up readily by the draining lymphatic channels. This allows for easy identification of their course. The visualisation of the lumen of the lymphatic vessel facilitates microsurgical anastomosis. The patency of the anastomosis is also demonstrated by the dynamic pumping action of the lymphatic within the vessels. Patent blue dye staining during lymphaticovenular anastomosis is a simple, effective and safe method for mapping suitable subdermal lymphatics, allowing for speedier dissection of the lymphatic vessels intraoperatively. This technique also helps in the confirmation of the success of the lymphaticovenular anastomosis.

  20. First-principles study of Carbz-PAHTDDT dye sensitizer and two Carbz-derived dyes for dye sensitized solar cells

    CERN Document Server

    Mohammadi, Narges

    2014-01-01

    Two new carbazole-based organic dye sensitizers are designed and investigated in silico. These dyes are designed through chemical modifications of the conjugated bridge of a reference organic sensitizer known as Carbz-PAHTDDT (S9) dye. The aim of designing these dyes was to reduce the energy gap between their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and to red-shift their absorption response compared to those of the reference S9 dye sensitizer. This reference dye has a reported promising efficiency when coupled with ferrocene-based electrolyte composition. To investigate geometric and electronic structure, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were conducted on the new dyes as well as the reference dye. The present study indicated that the long-range correction to the theoretical model in the TD-DFT simulation is important to produce accurate absorption wavelengths.The theoretical studies have shown a reduced HOMO-LUMO gap ...

  1. Investigation of hair dye deposition, hair color loss, and hair damage during multiple oxidative dyeing and shampooing cycles.

    Science.gov (United States)

    Zhang, Guojin; McMullen, Roger L; Kulcsar, Lidia

    2016-01-01

    Color fastness is a major concern for consumers and manufacturers of oxidative hair dye products. Hair dye loss results from multiple wash cycles in which the hair dye is dissolved by water and leaches from the hair shaft. In this study, we carried out a series of measurements to help us better understand the kinetics of the leaching process and pathways associated with its escape from the fiber. Hair dye leaching kinetics was measured by suspending hair in a dissolution apparatus and monitoring the dye concentration in solution (leached dye) with an ultraviolet-visible spectrophotometer. The physical state of dye deposited in hair fibers was evaluated by a reflectance light microscopy technique, based on image stacking, allowing enhanced depth of field imaging. The dye distribution within the fiber was monitored by infrared spectroscopic imaging of hair fiber cross sections. Damage to the ultrafine structure of the hair cuticle (surface, endocuticle, and cell membrane complex) and cortex (cell membrane complex) was determined in hair cross sections and on the hair fiber surface with atomic force microscopy. Using differential scanning calorimetry, we investigated how consecutive coloring and leaching processes affect the internal proteins of hair. Further, to probe the surface properties of hair we utilized contact angle measurements. This study was conducted on both pigmented and nonpigmented hair to gain insight into the influence of melanin on the hair dye deposition and leaching processes. Both types of hair were colored utilizing a commercial oxidative hair dye product based on pyrazole chemistry.

  2. The comparison of spectra and dyeing properties of new azonaphthalimide with analogues azobenzene dyes on natural and synthetic polymers

    Directory of Open Access Journals (Sweden)

    Mozhgan Hosseinnezhad

    2017-05-01

    Full Text Available The aim of the present research was to prepare new acid dyes based on naphthalimides. In this respect a series of monoazo acid dyes have been obtained using 4-amino-N-methyl (alternatively N-butyl-1,8-naphthalimide, aniline and p-nitroaniline as diazo components. 2-Naphthol-6-sulfonic acid (Schaeffer’s acid and 1-naphthol-8-amino-3,6-disulfonic acid (H-acid were used as coupling components. The spectrophotometric properties of the synthesized dyes were investigated in various solvents and compared with analogues azobenzene dyes. It is found, when acid dyes are applied in various solvents and different pH, additional bathochromically shifted bands of different intensity appear in the electronic spectra. This effect is caused by the occurrence of the equilibrium of azo and hydrazone forms in the dyes. The synthesized acid dyes were applied on wool fabrics in order to consider their dyeing properties, fastnesses and the obtainable color gamut. The synthesized dyes represented that they have the ability of dyeing wool and polyamide fabrics and give red to violet hues with good wash, medium light, and good milling and perspiration fastnesses.

  3. Synthesis and investigation of antimicrobial activity and spectrophotometric and dyeing properties of some novel azo disperse dyes based on naphthalimides.

    Science.gov (United States)

    Shaki, Hanieh; Gharanjig, Kamaladin; Khosravi, Alireza

    2015-01-01

    A series of novel disperse dyes containing azo group were synthesized through a diazotization and coupling process. The 4-amino-N-2-aminomethylpyridine-1,8-naphthalimide was diazotized by nitrosylsulphuric acid and coupled with various aromatic amines such as N,N-diethylaniline, N,N-dihydroxyethylaniline, 8-hydroxyquinoline, and 2-methylindole. Chemical structures of the synthesized dyes were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), proton nuclear magnetic resonance ((1) H NMR), carbon nuclear magnetic resonance ((13) C NMR), elemental analysis, and ultraviolet-visible (UV-visible) spectroscopy. The spectrophotometric data of all dyes were evaluated in various solvents with different polarity. Eventually, the dyes were applied on polyamide fabrics in order to investigate their dyeing properties. The fastness properties of the dyed fabrics such as wash, light, and rubbing fastness degrees were measured by standard methods. Moreover, the color gamut of the synthesized dyes was measured on polyamide fabrics. Results indicated that some of the synthesized dyes were able to dye polyamide fabrics with deep shades. They had very good wash and rubbing fastness degrees and moderate-to-good light fastness on polyamide fabrics. The antibacterial and antifungal activities of the synthesized dyes were evaluated in soluble state and on the dyed fabrics. The results indicated that dye 2 containing N,N-dihydroxyethylaniline as coupler had the highest activity against all the bacteria and fungi used. © 2015 American Institute of Chemical Engineers.

  4. The influence of the addition of dye surface modifier on the performance of transparent dye sensitized solar cells

    Science.gov (United States)

    Rosa, Erlyta Septa; Shobih, Retnaningsih, Lilis; Muliani, Lia; Hidayat, Jojo

    2017-11-01

    The light-harvesting properties and charge injection kinetics of dye molecules play a significant role to improve the performance of dye-sensitized solar cells (DSSC). Dyes based on metal complexes with ruthenium complexes also a variety of metal-organic dyes such as Zn-porphyrin derivatives have been used. The requirements for dye to function as a photosensitizer in DSSC are the absorption in the visible or near-infrared regions of the solar spectrum and the binding to the semiconductor TiO2. In order to interact with the TiO2 surface it is preferable that the dye has a functional group as anchoring group such as carboxylic or other peripheral acidic. The carboxylic group is the most frequently used anchoring group, as in ruthenium-complex based dyes. However, carboxylic acid as an anchoring group is still not enough for conducting in electron injection to TiO2. In this research, 0.87 mg phosphonic acid is added to N719 and Z907 ruthenium-complex based dyes, rspectively, as a surface modifier to strengthen the anchoring group. The addition of dyes surface modifier on the transparent DSSC device performance is investigated. Under illumination of 500 Wm-2, the power conversion efficiency (PCE) of DSSC using N719 ruthenium increases from 2.09 % to 3.22 % by the addition of surface modifier. However, different results are obtained on Z907 dye, where efficiency decreases from 2.02 % to 1.58 %.

  5. Dye-Sensitized Approaches to Photovoltaics

    Science.gov (United States)

    Grätzel, Michael

    2008-03-01

    Sensitization of wide band-gap semiconductors to photons of energy less than the band-gap is a key step in two technically important processes - panchromatic photography and photoelectrochemical solar cells. In both cases the photosensitive species is not the semiconductor - silver halide or metal oxide - but rather an electrochemically active dye. The gap between the highest occupied molecular level (HOMO) and the lowest unoccupied molecular level (LUMO) is less than the band-gap of the semiconductor with which it is associated. It can therefore absorb light of a wavelength longer than that to which the semiconductor itself is sensitive. The electrochemical process is initiated when the dye molecule relaxes from its photoexcited level by electron injection into the semiconductor, which therefore acts as a photoanode. If the dye is in contact with a redox electrolyte, the negative charge represented by the lost electron can be recovered from the reduced state of the redox system, which in return is regenerated by charge transfer from a cathode. An external load completes the electrical circuit. The system therefore represents a conversion of the energy of absorbed photons into an electrical current by a regenerative device in every functional respect analogous to a solid-state photovoltaic cell. As in any engineering system, choice of materials, their optimization and their synergy are essential to efficient operation. While a semiconductor-electrolyte contact is analogous to a Schottky contact, in that a barrier is established between two materials of different conduction mechanism, with the possibility of optical absorption, charge carrier pair generation and separation, it should be remembered that the photogenerated valence band hole in the semiconductor represents a powerful oxidizing agent. Given that the band-gap is related to the strength and therefore the stability of chemical bonding within the semiconductor, for narrow-gap materials the most likely

  6. Parametric Optimization of Dye-Sensitized Solar Cells Using Far red Sensitizing Dye with Cobalt Electrolyte

    Science.gov (United States)

    Pradhan, A.; Saikiran, M.; Kapil, G.; Pandey, S. S.; Hayase, S.

    2017-11-01

    A far-red sensitizing dye SQ-75 has been employed as a model sensitizer with Co(bpy)2+/3+ redox electrolytes to fabricate dye-sensitized solar cells (DSSCs) and optimize the various device parameters which influence the overall photoconversion efficiency (PCE). It has been found that the optimization of the TiO2 thickness, surface treatment with TiCl4, and an optimum amount of the chenodeoxycholic acid (CDCA) as coadsorber are necessary to attain the overall improved PCE. TiCl4 surface treatment on both FTO and TiO2 has been found to outperform as compared to their untreated counterparts owing to the suppression of the charge recombination. DSSCs with an optimized TiO2 thickness of 6 μm and CDCA concentration of 4 mM have exhibited best performance due to enhanced photon harvesting and reduced dye aggregation, respectively.

  7. Triple dye plus rubbing alcohol versus triple dye alone for umbilical cord care.

    Science.gov (United States)

    Suliman, Alawia K; Watts, Heidi; Beiler, Jessica; King, Tonya S; Khan, Sana; Carnuccio, Marybeth; Paul, Ian M

    2010-01-01

    Current practices for umbilical cord care vary across centers, but the evidence regarding these practices and their impact on cord separation, complications, and health care use are limited. The objective of this study was to compare the effect of triple dye alone (brilliant green, crystal violet, and proflavine hemisulfate) versus triple dye plus rubbing alcohol (isopropyl alcohol) twice daily on time to umbilical cord separation, complications, and health care use. For the 90 newborns who completed the study, there were no significant differences between treatment groups for time to cord separation, cord-related morbidities, or cord-related urgent care. Based on these study results, there does not appear to be significant benefit to the addition of twice daily applications of rubbing alcohol to neonatal umbilical cords following triple dye treatment after birth.

  8. FATE OF WATER SOLUBLE AZO DYES IN THE ACTIVATED SLUDGE PROCESS

    Science.gov (United States)

    The objective of this study was to determine the partitioning of water soluble azo dyes in the activated sludge process (ASP). Azo dyes are of concern because some of the dyes, dye precursors , and/or their degradation products such as aromatic amines (which are also dye precurso...

  9. Preparation of 6-hydroxyindolines and their use for preparation of novel laser dyes

    Science.gov (United States)

    Field, G.F.; Hammond, P.R.

    1993-10-26

    A novel method is described for the synthesis of 6-hydroxyindolines and new fluorescent dyes produced therefrom, which dyes are ring-constrained indoline-based rhodamine class dyes. These dyes have absorption and emission spectra which make them particularly useful in certain dye laser applications.

  10. The Effect of Two African Mineral Dyes on the Activity of Alkaline ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    The use of hair dye is fast gaining popularity especially among ladies and old men. Young ladies engage in the use of dyes mainly for fashion while old men use dyes to mask their grey hair. Dyes are basically of two types namely natural dyes and synthetic .... organic and inorganic components in the samples. The colour ...

  11. Optical properties of cyanine dyes in nanotubes of chrysotile asbestos

    Science.gov (United States)

    Starovoytov, Anton A.; Vartanyan, Tigran A.; Belotitskii, Vladimir I.; Kumzerov, Yuri A.; Sysoeva, Anna A.

    2017-08-01

    Optical properties of cyanine dye molecules incorporated in nanotubes of natural chrysotile asbestos are studied. The absorption and fluorescence spectra of dye in asbestos have the similar shapes as in the ethanol solution, apart from small blue shift of the maxima. The Stokes shift in asbestos is smaller than in the ethanol solution. The fluorescence decay times of the dyes in asbestos nanotubes are found to be larger than that in the case of thin films of the same dyes formed on the transparent dielectric supports. This observation is rationalized in terms of the stereoisomerization hindrance in the excited electronic state of dye molecules. At the same time linear dichroism and fluorescence anisotropy observed in the experiment indicate that the embedded dye molecules are well-isolated monomer oriented predominantly along asbestos nanotubes.

  12. Biosorption of Azo dyes by spent Rhizopus arrhizus biomass

    Science.gov (United States)

    Salvi, Neeta A.; Chattopadhyay, S.

    2017-10-01

    In the present study, spent Rhizopus arrhizus biomass was used for the removal of six azo dyes from aqueous solutions. The dye removal capacity of the biomass was evaluated by conducting batch tests as a function of contact time, biomass dosage, pH and initial dye concentrations. The pseudo-second-order kinetic model fitted well with the experimental data with correlation coefficients greater than 0.999, suggesting that chemisorptions might be the rate limiting step. The equilibrium sorption data showed good fit to the Langmuir isotherm model. Among the six dyes tested, the maximum monolayer adsorption capacity for fast red A and metanil yellow was found to be 108.8 and 128.5 mg/g, respectively. These encouraging results suggest that dead Rhizopus arrhizus biomass could be a potential biomaterial for the removal of azo dyes from aqueous dye solution.

  13. Co-sensitization of organic dyes for efficient dye-sensitized solar cells.

    Science.gov (United States)

    Cheng, Ming; Yang, Xichuan; Li, Jiajia; Zhang, Fuguo; Sun, Licheng

    2013-01-01

    Novel cyanine dyes, in which a tetrahydroquinoline derivative is used as an electron donor and 1-butyl-5-carboxy-3, 3-dimethyl-indol-1-ium moiety is used as an electron acceptor and anchoring group, were designed and synthesized for application in dye-sensitized solar cells. The photovoltaic performance of these solar cells depends markedly on the molecular structure of the dyes in terms of the n-hexyl chains and the methoxyl unit. Retardation of charge recombination caused by the introduction of n-hexyl chains resulted in an increase in electron lifetime. As a consequence, an improvement of open-circuit photovoltage (V(oc)) was achieved. Also, the electron injection efficiencies were improved by the introduction of methoxyl moiety, which led to a higher short-circuit photocurrent density (J(sc)). The highest average efficiency of the sensitized devices (η) was 5.6% (J(sc)=13.3 mA cm(-2), V(oc)=606 mV, and fill factor FF=69.1%) under 100 mW cm(-2) (AM 1.5G) solar irradiation. All of these dyes have very high absorption extinction coefficients and strong absorption in a relatively narrow spectrum range (500-650 nm), so one of our organic dyes was explored as a sensitizer in co-sensitized solar cells in combination with the other two other existing organic dyes. Interestingly, a considerably improved photovoltaic performance of 8.2% (J(sc)=20.1 mA cm(-2), V(oc)=597 mV, and FF=68.3%) was achieved and the device showed a panchromatic response with a high incident photon-to-current conversion efficiency exceeding 85% in the range of 400-700 nm. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Panchromatic Response in Solid-State Dye-Sensitized Solar Cells Containing Phosphorescent Energy Relay Dyes

    KAUST Repository

    Yum, Jun-Ho

    2009-11-23

    Running relay: Incorporating an energyrelay dye (ERD) into the hole transporter of a dye-sensitized solar cell increased power-conversion efficiency by 29% by extending light harvesting into the blue region. In the operating mechanism (see picture), absorption of red photons by the sensitizer transfers an electron into TiO2 and a hole into the electrolyte. Blue photons absorbed by the ERD are transferred by FRET to the sensitizer. Chemical Equitation Presentation © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

  15. Dye sensitized photovoltaic cells: Attaching conjugated polymers to zwitterionic ruthenium dyes

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Biancardo, M.

    2006-01-01

    The synthesis of a zwitterionic ruthenium dye that binds to anatase surfaces and has a built-in functionality that allows for the attachment of a conjugated polymer chain is presented. The system was found to adsorb on the surface of anatase anchored by the ruthenium dye. Two types of devices were...... and the complex was adsorbed onto the surface before evaporation of gold electrodes. Alternative devices were obtained by spincoating of the polymer solution onto PEDOT:PSS covered indium-doped tin oxide substrates. PEC solar cells gave the best results and the main finding was that the polymer chain served...

  16. Synthesis of dye linked conducting block copolymers, dye linked conducting homopolymers and preliminary application to photovoltaics

    DEFF Research Database (Denmark)

    Krebs, Frederik C; Hagemann, O.; Jørgensen, M.

    2004-01-01

    A synthetic approach to the synthesis of a large super molecule composed of two chemically different conducting polymer blocks with, respectively, high and low lying electronic energy levels linked through a porphyrin dye molecule is presented. The synthetic strategies to these molecular architec......A synthetic approach to the synthesis of a large super molecule composed of two chemically different conducting polymer blocks with, respectively, high and low lying electronic energy levels linked through a porphyrin dye molecule is presented. The synthetic strategies to these molecular...

  17. A New Generation of Glycoconjugated Azo Dyes Based on Aminosugars

    OpenAIRE

    Guazzelli, Lorenzo; Catelani, Giorgio; D’Andrea, Felicia

    2015-01-01

    The third generation of glycoconjugated azo dyes (GADs) was prepared linking monoazo dyes to 6-amino-6-deoxy-d-galactose or 6′amino-6′-deoxylactose through mixed amido-ester connections. The complementary conjugation reactions were studied using the succinyl derivative of either the acetal protected aminosugar or the azo dye. Target “naturalized” GADs were obtained after acid hydrolysis of the acetal protecting groups present on the sugar moiety.

  18. A New Generation of Glycoconjugated Azo Dyes Based on Aminosugars

    Directory of Open Access Journals (Sweden)

    Lorenzo Guazzelli

    2015-01-01

    Full Text Available The third generation of glycoconjugated azo dyes (GADs was prepared linking monoazo dyes to 6-amino-6-deoxy-d-galactose or 6′amino-6′-deoxylactose through mixed amido-ester connections. The complementary conjugation reactions were studied using the succinyl derivative of either the acetal protected aminosugar or the azo dye. Target “naturalized” GADs were obtained after acid hydrolysis of the acetal protecting groups present on the sugar moiety.

  19. Adsorption Properties of Lac Dyes on Wool, Silk, and Nylon

    Directory of Open Access Journals (Sweden)

    Bo Wei

    2013-01-01

    Full Text Available There has been growing interest in the dyeing of textiles with natural dyes. The research about the adsorption properties of natural dyes can help to understand their adsorption mechanism and to control their dyeing process. This study is concerned with the kinetics and isotherms of adsorption of lac dyes on wool, silk, and nylon fibers. It was found that the adsorption kinetics of lac dyes on the three fibers followed the pseudosecond-order kinetic model, and the adsorption rate of lac dyes was the fastest for silk and the slowest for wool. The activation energies for the adsorption process on wool, silk, and nylon were found to be 107.15, 87.85, and 45.31 kJ/mol, respectively. The adsorption of lac dyes on the three fibers followed the Langmuir mechanism, indicating that the electrostatic interactions between lac dyes and those fibers occurred. The saturation values for lac adsorption on the three fibers decreased in the order of wool > silk > nylon; the Langmuir affinity constant of lac adsorption on nylon was much higher than those on wool and silk.

  20. UV protection property of cloths dyed with flavonoid plant dye

    OpenAIRE

    小林, 優子; 鈴木, 恒夫

    2011-01-01

    The aging of skin and pigmentation are caused by the ultraviolet radiation (UV). It is important for UV protection of clothes to protection of human body. Materials, dyes and tissue textiles were the factors that affect UV protection of clothes. Among them, dyes were paid attention and vegetable dyes were used in this experiment. Plant pigment in a cell was an essential material of growth and sustaining life. And it was related with sun light. This study was examined about the dyeing with oni...

  1. Phase change material for efficient removal of crystal violet dye.

    Science.gov (United States)

    Haik, Yousef; Qadri, Shahnaz; Ganoe, Ashley; Ashraf, Sarmadia; Sawafta, Reyad

    2010-04-15

    Hazardous dye removal and recovery from wastewater requires efficient capturing material. We report a phase change material (PCM) with phase change temperature of 16 degrees C giving up to 98% removal of crystal violet in few minutes. The PCM was found to collect 54 times of its weight soluble dye. The dye adsorption kinetics obeys a second order pseudo rate. Upon cooling the PCM to below 16 degrees C it gels and enabled solid removal of the captured dye. 2009 Elsevier B.V. All rights reserved.

  2. Removal of synthetic food dyes in aqueous solution by Octolig.

    Science.gov (United States)

    Martin, Dean F; Alessio, Rachael J; McCane, Cheryl H

    2013-01-01

    We studied six of the seven food dyes commonly used, e.g., FD&C Blue No. 1 and No. 2, Green No. 3, Red No. 3 and No. 40, Yellow No. 5 and No. 6. Quantitative removal was achieved by passage of dyes in aqueous solutions over chromatography columns packed with Octolig, a polyethylenediimine covalently attached to high-surface-area silica. A structural feature most of the dyes have in common are the presence of sulfonate groups attached to aromatic molecules. Prior studies and the current one indicated that the seventh food dye (Green No. 3) should also be quantitatively removed. Matrix effects were considered, but none were observed.

  3. Disperse dyeing properties of (easy dyeable polyester)/spandex blend

    Science.gov (United States)

    Rahman, M. M.; Mamun Kabir, S. M.; Kim, H.; Koh, J.

    2017-10-01

    Using a low and a high energy disperse dye, several dyeing properties, like colour depth, partition ratio, degree of dye exhaustion, build–up and fastness properties of (easy dyeable polyester)/spandex blend were thoroughly investigated. Various dyeing temperatures ranging from 90°C to 130°C were applied. To check its performance, the conventional (regular polyester/spandex) blend was also dyed. (easy dyeable polyester)/spandex blend showed higher dyeability on PET and lower staining on spandex at low temperature compared to (regular polyester)/spandex blend..

  4. Solid state microcavity dye lasers fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Nilsson, Daniel; Nielsen, Theodor; Kristensen, Anders

    2004-01-01

    We present a solid state polymer microcavity dye laser, fabricated by thermal nanoimprint lithography (NIL) in a dye-doped thermoplast. The thermoplast poly-methylmethacrylate (PMMA) is used due to its high transparency in the visible range and its robustness to laser radiation. The laser dye...... propagating TE–TM modes. The laser cavity has the lateral shape of a trapezoid, supporting lasing modes by reflection on the vertical cavity walls. The solid polymer dye lasers emit laterally through one of the vertical cavity walls, when pumped optically through the top surface by means of a frequency...

  5. Cosensitization with Vat-Based Organic Dyes for Enhanced Spectral Response of Dye-Sensitized Solar Cells

    Science.gov (United States)

    Hosseinnezhad, Mozhgan

    2017-04-01

    Cosensitization using two organic dyes with supplementary absorption spectra on a photoelectrode is an effective method for improving the photovoltaic properties of dye-sensitized solar cells. Two organic dyes based on indigo and thioindigo have been synthesized, purified, and used to sensitize solar cells with spectral response extending across the entire visible region. To improve their photoelectric properties, different molar ratios were investigated, yielding total efficiency of 6.17% at dye 1:dye 2 = 4:6. The effect of the concentration of Cheno antiaggregation agent on the performance of the dye-sensitized solar cells was also considered. The results demonstrate that higher conversion efficiency ( η = 6.82%) was achieved with 10 × 10-3 M Cheno. Finally, the performance of cosensitized solar cells was measured at different temperatures between 10°C and 50°C. The results indicated that J sc decreased with increasing temperature, directly affecting the conversion efficiency.

  6. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho [Kyungpook National University, Daegu (Korea, Republic of); Oh, Sang Jin [Phoenix Materials, Gumi (Korea, Republic of)

    2012-11-15

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ∼ 500 .deg. C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  7. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    Science.gov (United States)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho; Oh, Sang Jin

    2012-11-01

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ˜ 500 °C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  8. Natural dye extracted from karkadah and its application in dye-sensitized solar cells: experimental and density functional theory study.

    Science.gov (United States)

    Reda, S M; Soliman, K A

    2016-02-01

    This work presents an experimental and theoretical study of cyanidin natural dye as a sensitizer for ZnO dye-sensitized solar cells. ZnO nanoparticles were prepared using ammonia and oxalic acid as a capping agent. The calculated average size of the synthesized ZnO with different capping agents was found to be 32.1 nm. Electronic properties of cyanidin and delphinidin dye were studied using density functional theory (DFT) and time-dependent DFT with a B3LYP/6-31G(d,p) level. By comparing the theoretical results with the experimental data, the cyanidin dye can be used as a sensitizer in dye-sensitized solar cells. An efficiency of 0.006% under an AM-1.5 illumination at 100  mW/cm(2) was attained. The influence of dye adsorption time on the solar cell performance is discussed.

  9. A Note on the Dyeing of Wool Fabrics Using Natural Dyes Extracted from Rotten Wood-Inhabiting Fungi

    Directory of Open Access Journals (Sweden)

    Vicente A. Hernández

    2018-02-01

    Full Text Available Fungal isolates obtained from rotten wood samples were identified and selected by their ability to produce fungal dyes in liquid media. Fungal isolates produced natural extracellular dyes with colors ranging from red to orange, yellow and purple. Dyes from two of these fungi, Talaromyces australis (red and Penicillium murcianum (yellow, were extracted and used to dye wool samples in a Data Color Ahiba IR Pro-Trade (model Top Speed II machine. The protein nature of wool interacted well with the fungal dyes producing colors suitable for textile applications when used to a concentration of 0.1 g L−1. Results on color fastness when washing confirmed the affinity of the dyes with wool as the dyed samples kept their color in acceptable ranges after washing, without the implementation of mordanting pretreatments or the use of fixing agents.

  10. Database of two-dimensional polyacrylamide gel electrophoresis of proteins labeled with CyDye DIGE Fluor saturation dye.

    Science.gov (United States)

    Fujii, Kazuyasu; Kondo, Tadashi; Yokoo, Hideki; Okano, Tetsuya; Yamada, Masayo; Yamada, Tesshi; Iwatsuki, Keiji; Hirohashi, Setsuo

    2006-03-01

    CyDye DIGE Fluor saturation dye (saturation dye, GE Healthcare Amersham Biosciences) enables highly sensitive 2-D PAGE. As the dye reacts with all reduced cysteine thiols, 2-D PAGE can be performed with a lower amount of protein, compared with CyDye DIGE Fluor minimal dye (GE Healthcare Amersham Biosciences), the sensitivity of which is equivalent to that of silver staining. We constructed a 2-D map of the saturation dye-labeled proteins of a liver cancer cell line (HepG2) and identified by MS 92 proteins corresponding to 123 protein spots. Functional classification revealed that the identified proteins had chaperone, protein binding, nucleotide binding, metal ion binding, isomerase activity, and motor activity. The functional distribution and the cysteine contents of the proteins were similar to those in the most comprehensive 2-D database of hepatoma cells (Seow et al.., Electrophoresis 2000, 21, 1787-1813), where silver staining was used for protein visualization. Hierarchical clustering on the basis of the quantitative expression profiles of the 123 characterized spots labeled with two charge- and mass-matched saturation dyes (Cy3 and Cy5) discriminated between nine hepatocellular carcinoma cell lines and primary cultured hepatocytes from five individuals, suggesting the utility of saturation dye and our database for proteomic studies of liver cancer.

  11. Theoretical study on the application of double-donor branched organic dyes in dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yan-Hong; Liu, Rui-Rui [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China); Zhu, Kai-Li [College of Chemistry and Life Science, Gansu Normal University for Nationalities, Hezuo, 747000, Gansu (China); Song, Yan-Lin [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China); Geng, Zhi-Yuan, E-mail: zhiyuangeng@126.com [Gansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Key Laboratory of Eco-environment-related Polymer Materials, Ministry of Education, Northwest Normal University, Lanzhou, 730070, Gansu (China)

    2016-09-15

    A novel organic dye with 2D-A structure has been designed and calculated whereby density functional theory (DFT) and time-dependent density functional theory (TD-DFT) for dye-sensitized solar cells. The double-donor branched dye which was consisted of two separated light-harvesting moieties was beneficial to photocurrent generation. First, we discussed the effects of different donor chains on photoelectric performance in the dye molecule, using the DTP-B8 which was a previously reported structure as the reference. Only to conclude that the suitable length can achieve the satisfactory efficiency. Secondly, to modify and sift potential sensitizers further, three series of dyes (BC-series, CB-series and CC-series) were designed and characterized. The increased molar extinction coefficient and the red-shifted λ{sub max} was attributed to an increasing in electron conjunction. This work presented a new route to design sensitizers that provide two channels for donating more electrons and improve the final efficiency. It is expected to provide some theoretical guidance on designing and synthetizing high efficiency photosensitive dye in the future experiments. - Highlights: • A novel organic dye with 2D-A structure was designed and characterized. • The double-donor branched dye was consisted of two separated light-harvesting paths. • The double-donor branched dye was beneficial to photocurrent generation. • The molar extinction coefficient was greatly improved in this novel structure. • Four promising candidates have been screened out.

  12. Synthesis, dyeing performance on polyester fiber and antimicrobial studies of some novel pyrazolotriazine and pyrazolyl pyrazolone azo dyes

    Directory of Open Access Journals (Sweden)

    Hala F. Rizk

    2017-05-01

    Full Text Available 5-Amino-4-heterylazo-3-phenyl-1H-pyrazoles (2a–d were diazotized and coupled with malononitrile to give pyrazoloazo malononitrile which by heating in glacial acetic acid gave novel pyrazolo[5,1-c][1,2,4]triazine dyes (3a–d. Also, some diazopyrazolyl pyrazolone dyes (4a–h were synthesized by diazotization of 2a–d and coupled with some pyrazolone derivatives. The structure of the synthesized dyes was determined by elemental analysis and spectral data. All the synthesized compounds were applied as disperse dyes and their dyeing performance on polyester fabric was studied. The fastness and colorimetric properties were measured. The results revealed that the monoazo dyes have good fastness and good to moderate affinity to polyester fabric than diazo dyes. In addition, the synthesized dyes were screened for their antimicrobial activities against Staphylococcus aureus, Pseudomonas aeruginosa (Gram positive, Bacillus subtitles, Escherichia coli (Gram negative and Candida albicans, Aspergillus niger (Fungi. The results revealed that most of the prepared dyes have high antibacterial activity.

  13. Biosorption and biodegradation of a sulfur dye in high-strength dyeing wastewater by Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Nguyen, Thai Anh; Fu, Chun-Chieh; Juang, Ruey-Shin

    2016-11-01

    The ability of the bacterial strain Acidithiobacillus thiooxidans to remove sulfur blue 15 (SB15) dye from water samples was examined. This bacterium could not only oxidize sulfur compounds to sulfuric acid but also promote the attachment of the cells to the surface of sulfidic particles, therefore serving as an efficient biosorbent. The biosorption isotherms were better described by the Langmuir equation than by the Freundlich or Dubinin-Radushkevich equation. Also, the biosorption process followed the pseudo-second-order kinetics. At pH 8.3 and SB15 concentrations up to 2000 mg L(-1) in the biomass/mineral salt solution, the dye removal and decolorization were 87.5% and 91.4%, respectively, following the biosorption process. Biodegradation was proposed as a subsequent process for the remaining dye (250-350 mg L(-1)). A central composite design was used to analyze independent variables in the response surface methodology study. Under the optimal conditions (i.e., initial dye concentration of 300 mg L(-1), initial biomass concentration of 1.0 g L(-1), initial pH of 11.7, and yeast extract dose of 60 mg L(-1)), up to 50% of SB15 was removed after 4 days of biodegradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Rhodanine dyes for dye-sensitized solar cells : spectroscopy, energy levels and photovoltaic performance.

    Science.gov (United States)

    Marinado, Tannia; Hagberg, Daniel P; Hedlund, Maria; Edvinsson, Tomas; Johansson, Erik M J; Boschloo, Gerrit; Rensmo, Håkan; Brinck, Tore; Sun, Licheng; Hagfeldt, Anders

    2009-01-07

    Three new sensitizers for photoelectrochemical solar cells were synthesized consisting of a triphenylamine donor, a rhodanine-3-acetic acid acceptor and a polyene connection. The conjugation length was systematically increased, which resulted in two effects: first, it led to a red-shift of the optical absorption of the dyes, resulting in an improved spectral overlap with the solar spectrum. Secondly, the oxidation potential decreased systematically. The excited state levels were, however, calculated to be nearly stationary. The experimental trends were in excellent agreement with density functional theory (DFT) computations. The photovoltaic performance of this set of dyes as sensitizers in mesoporous TiO2 solar cells was investigated using electrolytes containing the iodide/triiodide redox couple. The dye with the best absorption characteristics showed the poorest solar cell efficiency, due to losses by recombination of electrons in TiO2 with triiodide. Addition of 4-tert butylpyridine to the electrolyte led to a strongly reduced photocurrent for all dyes due to a reduced electron injection efficiency, caused by a 0.15 V negative shift of the TiO2 conduction band potential.

  15. Organic Dyes Containing Coplanar Dihexyl-Substituted Dithienosilole Groups for Efficient Dye-Sensitised Solar Cells

    Directory of Open Access Journals (Sweden)

    Ciaran Lyons

    2017-01-01

    Full Text Available A chromophore containing a coplanar dihexyl-substituted dithienosilole (CL1 synthesised for use in dye-sensitised solar cells displayed an energy conversion efficiency of 6.90% under AM 1.5 sunlight irradiation. The new sensitiser showed a similar fill factor and open-circuit voltage when compared with N719. Impedance measurements showed that, in the dark, the charge-transfer resistance of a cell using CL1 in the intermediate-frequency region was higher compared to N719 (69.8 versus 41.3 Ω. Under illumination at AM 1.5G-simulated conditions, the charge-transfer resistances were comparable, indicative of similar recombination rates by the oxidised form of the redox couple. The dye showed instability in ethanol solution, but excellent stability when attached to TiO2. Classical molecular dynamics indicated that interactions between ethanol and the dye are likely to reduce the stability of CL1 in solution form. Time-dependent density functional theory studies were performed to ascertain the absorption spectrum of the dye and assess the contribution of various transitions to optical excitation, which showed good agreement with experimental results.

  16. Difference gel electrophoresis (DIGE) using CyDye DIGE fluor minimal dyes.

    Science.gov (United States)

    Chakravarti, Bulbul; Gallagher, Sean R; Chakravarti, Deb N

    2005-02-01

    One- and two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1- and 2-D SDS-PAGE) have been widely used for the separation and quantitative estimation of proteins. Following electrophoresis, the gels are stained appropriately to visualize the proteins. Difference gel electrophoresis (DIGE) is a new technique in which different protein samples, individually labeled with specific CyDyes, are combined together followed by electrophoresis and post electrophoretic co-detection and co-analysis on the same gel. CyDye DIGE fluor minimal dyes, which consist of three different CyDyes with different spectral characteristics, have been widely used for such purposes. The technique is highly sensitive with a wide dynamic range for detection of proteins and compatible with state-of-the-art protein identification techniques using mass spectrometry. Although DIGE is mainly used to compare differential expression of various protein samples using 2-D SDS-PAGE, 1-D DIGE also has important applications in quantitative proteomic studies.

  17. Decolorization of azo dyes by Geobacter metallireducens.

    Science.gov (United States)

    Liu, Guangfei; Zhou, Jiti; Chen, Congcong; Wang, Jing; Jin, Ruofei; Lv, Hong

    2013-09-01

    Geobacter metallireducens was found to be capable of decolorizing several azo dyes with different structures to various extents. Pyruvate, ethanol, acetate, propionate, and benzoate could support 66.3 ± 2.6-93.7 ± 2.1 % decolorization of 0.1 mM acid red 27 (AR27) in 40 h. The dependence of the specific decolorization rate on AR27 concentration (25 to 800 μM) followed Michaelis-Menten kinetics (K m = 186.9 ± 1.4 μΜ, V max = 0.65 ± 0.02 μmol mg protein(-1) h(-1)). Enhanced AR27 decolorization was observed with the increase of cell concentrations ranging from 7.5 to 45 mgL(-1). AR27 decolorization by G. metallireducens was retarded by the presence of goethite, which competed electrons with AR27 and was reduced to Fe(II). The addition of low concentrations of humic acid (1-100 mgL(-1)) or 2-hydroxy-1,4-naphthoquinone (0.5-50 μM) could improve the decolorization performance of G. metallireducens. High-performance liquid chromatography analysis suggested reductive pathway to be responsible for decolorization. This was the first study on azo dye decolorization by Geobacter strain and might improve our understanding of natural attenuation and bioremediation of environments polluted by azo dyes.

  18. Electrochemical, linear optical, and nonlinear optical properties and interpretation by density functional theory calculations of (4-N,N-dimethylaminostyryl)-pyridinium pendant group associated with polypyridinic ligands and respective multifunctional metal complexes (Ru(II) or Zn(II)).

    Science.gov (United States)

    Dumur, Frédéric; Mayer, Cédric R; Hoang-Thi, Khuyen; Ledoux-Rak, Isabelle; Miomandre, Fabien; Clavier, Gilles; Dumas, Eddy; Méallet-Renault, Rachel; Frigoli, Michel; Zyss, Joseph; Sécheresse, Francis

    2009-09-07

    The synthesis, linear optical and nonlinear optical properties, as well as the electrochemical behavior of a series of pro-ligands containing the 4-(4-N,N-dimethylaminostyryl)-1-methyl pyridinium (DASP(+)) group as a push-pull moiety covalently linked to terpyridine or bipyridine as chelating ligands are reported in this full paper. The corresponding multifunctional Ru(II) and Zn(II) complexes were prepared and investigated. The structural, electronic, and optical properties of the pro-ligands and the ruthenium complexes were investigated using density functional theory (DFT) and time-dependent (TD) DFT calculations. A fairly good agreement was observed between the experimental and the calculated electronic spectra of the pro-ligands and their corresponding ruthenium complexes. A quenching of luminescence was evidenced in all ruthenium complexes compared with the free pro-ligands but even the terpyridine-functionalized metal complexes exhibited detectable luminescence at room temperature. Second order nonlinear optical (NLO) measurements were performed by Harmonic Light Scattering and the contribution of the DASP(+) moieties (and their relative ordering) and the metal-polypyridyl core need to be considered to explain the nonlinear optical properties of the metal complexes.

  19. Melt sonoquenching: an affective process to obtain new hybrid material and achieve enhanced electrochromic performances based on V{sub 2}O{sub 5}/2,4,5-tris(1-methyl- 4-pyridinium)-imidazolide tetrafluoroborate nanofibers

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Renato S. de; Goulart, Juliana da S.; Miranda, Fabio S.; Ponzio, Eduardo A., E-mail: eaponzio@vm.uff.br [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Quimica

    2014-03-15

    Hybrid electrochromic materials are a very important class of compounds, because they enable new and/or better optical and electrochemical properties to be unfolded. This paper reports the synthesis of the new V{sub 2}O{sub 5}.1.26H{sub 2}O([C{sub 3}N{sub 2}(C{sub 6}H{sub 7}N){sub 3}]){sub 0.07} using the combination of two traditional methods, melting quenching and sonochemistry. The new material was characterized by several methods in order to verify the physical and chemical characteristics and its possible use as an electrochromic electrode. The organic guest provokes an interlayer spacing decrease of the inorganic matrix and the electrostatic interaction between the oxo groups of the V{sub 2}O{sub 5} matrix and the pyridinium rings of the organic guest demonstrate a strong interaction. The new hybrid nanostructure presented good reversibility and cyclability during 50 cycles, electrochromic efficiency of 22 cm{sup 2} C{sup -1} (410 nm) and 96 % color retention after 50 cycles of color changing. (author)'.

  20. 2-Methylpyridinium/pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olates as potent anticonvulsant agents—synthesis and crystal structure

    Energy Technology Data Exchange (ETDEWEB)

    Mangaiyarkarasi, G.; Kalaivani, D., E-mail: kalaivbalaj@yahoo.co.in [Affiliated to Bharathidasan University, Post Graduate and Research Department of Chemistry, Seethalakshmi Ramaswami College, Tiruchirappalli-620 002 (India)

    2013-12-15

    The molecular salt, 2-methylpyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropy-rimidin-4-olate) (I), is prepared from the ethanolic solution of 1-chloro-2,4-dinitrobenzene, pyrimidine-2,4,6-(1H,3H,5H)-trione (barbituric acid) and 2-methylpyridine at room temperature, and the molecular salt, pyridinium 5-(2,4-dinitrophenyl)-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate (II), is prepared from the same reactants, by dissolving them in hot DMSO and ethanol mixture at 70°C. The structures of I and II are characterized by visible, IR, {sup 1}H-NMR, {sup 13}C-NMR and elemental analysis and confirmed by single crystal X-ray analysis. Both the salts crystallize in triclinic crystal system with sp. gr. P-bar1. They possess noticeable anticonvulsant activity even at low concentration (25 mg/kg). Acute toxicity studies of these complexes indicate that LD{sub 50} values are greater than 1500 mg/kg and the tested animals do not show any behavioural changes.

  1. Photoactive dye-enhanced tissue ablation for endoscopic laser prostatectomy.

    Science.gov (United States)

    Ahn, Minwoo; Hau, Nguyen Trung; Van Phuc, Nguyen; Oh, Junghwan; Kang, Hyun Wook

    2014-11-01

    Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia (BPH) over 20 years. Recently, application of high laser power up to 200 W was often reported to swiftly remove a large amount of prostatic tissue. The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption and eventually to facilitate tissue vaporization with low laser power. Chicken breast tissue was selected as a target tissue due to minimal optical absorption at the visible wavelength. Four biocompatible photoactive dyes, including amaranth (AR), black dye (BD), hemoglobin powder (HP), and endoscopic marker (EM), were selected and tested in vitro with a customized 532 nm laser system with radiant exposure ranging from 0.9 to 3.9 J/cm(2) . Light absorbance and ablation threshold were measured with UV-Vis spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes. Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation efficiency principally increased with radiant exposure, dye concentration, and number of injection. Among the dyes, AR created the highest ablation rate of 44.2 ± 0.2 µm/pulse due to higher absorbance and lower ablation threshold. High aspect ratios up to 7.1 ± 0.4 entailed saturation behavior in the tissue ablation injected with AR and BD, possibly resulting from plume shielding and increased scattering due to coagulation. Preliminary tests on canine prostate with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation efficiency to 120 W with no injection, indicating 33% reduced laser power with almost equivalent performance. Due to

  2. Assessment of different dyes used in leakage studies.

    Science.gov (United States)

    Mente, Johannes; Ferk, Stephan; Dreyhaupt, Jens; Deckert, Andreas; Legner, Milos; Staehle, Hans Joerg

    2010-06-01

    The goal of this in vitro study was to identify the most suitable dye for endodontic dye leakage studies, which could be a further step towards standardisation. The root canals of 70 extracted, single-rooted human adult teeth were enlarged to apical size 50 using hand instruments. The teeth were divided into seven groups (n = 10 each), and all root canals were completely filled by injection with one of the following dyes: methylene blue 0.5% and 5%, blue ink, black ink, eosin 5%, basic fuchsin 0.5% and drawing ink. Transverse root sections from the coronal, middle and apical part of the roots were examined, and the percentage of the dentine penetrated by dye was evaluated by software-supported light microscopy. In addition, the range of particle size of drawing ink particles was evaluated. There were conspicuous differences in the relative dye penetration into the root dentine and the penetration behaviour in the different root sections (two-way ANOVA, both p < 0.0001). One dye (drawing ink) penetrated less into the root dentine compared with all the others (p <0.0001). The particle size of this agent (0.1-2 microm) corresponds best with the size range of a representative selection of 21 species of pathogenic endodontic bacteria. Compared to the other dyes tested, drawing ink appears to be superior for use in endodontic dye leakage studies. The penetration behaviour into the root dentine of all the other dyes tested might be one factor that limits the applicability of these dyes in dye leakage studies.

  3. Textile dye degradation using nano zero valent iron: A review.

    Science.gov (United States)

    Raman, Chandra Devi; Kanmani, S

    2016-07-15

    Water soluble unfixed dyes and inorganic salts are the major pollutants in textile dyeing industry wastewater. Existing treatment methods fail to degrade textile dyes and have limitations too. The inadequate treatment of textile dyeing wastewater is a major concern when effluent is directly discharged into the nearby environment. Long term disposal threatens the environment, which needs reclamation. This article reviews the current knowledge of nano zero valent iron (nZVI) technique in the degradation of textile dyes. The application of nZVI on textile dye degradation is receiving great attention in the recent years because nZVI particles are highly reactive towards the pollutant, less toxic, and economical. The nZVI particles aggregate quickly with respect to time and the addition of supports such as resin, nickel, zinc, bentonite, biopolymer, kaolin, rectorite, nickel-montmorillonite, bamboo, cellulose, biochar, graphene, and clinoptilolite enhanced the stability of iron nanoparticles. Inclusion of supports may in turn introduce additional toxic pollutants, hence green supports are recommended. The majority of investigations concluded dye color removal as textile dye compound removal, which is not factual. Very few studies monitored the removal of total organic carbon and observed the products formed. The results revealed that partial mineralization of the textile dye compound was achieved. Instead of stand alone technique, nZVI can be integrated with other suitable technique to achieve complete degradation of textile dye and also to treat multiple pollutants in the real textile dyeing wastewater. It is highly recommended to perform more bench-scale and pilot-scale studies to apply this technique to the textile effluent contaminated sites. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Daylight-driven photocatalytic degradation of ionic dyes with negatively surface-charged In2S3 nanoflowers: dye charge-dependent roles of reactive species

    Science.gov (United States)

    Ge, Suxiang; Cai, Lejuan; Li, Dapeng; Fa, Wenjun; Zhang, Yange; Zheng, Zhi

    2015-12-01

    Even though dye degradation is a successful application of semiconductor photocatalysis, the roles of reactive species in dye degradation have not received adequate attention. In this study, we systematically investigated the degradation of two cationic dyes (rhodamine B and methylene blue) and two anionic dyes (methyl orange and orange G) over negatively surface-charged In2S3 nanoflowers synthesized at 80 °C under indoor daylight lamp irradiation. It is notable to find In2S3 nanoflowers were more stable in anionic dyes degradation compared to that in cationic dyes removal. The active species trapping experiments indicated photogenerated electrons were mainly responsible for cationic dyes degradation, but holes were more important in anionic dyes degradation. A surface-charge-dependent role of reactive species in ionic dye degradation was proposed for revealing such interesting phenomenon. This study would provide a new insight for preparing highly efficient daylight-driven photocatalyst for ionic dyes degradation.

  5. Dye solar cell research: EU delegation presentation

    CSIR Research Space (South Africa)

    Cummings, F

    2009-11-09

    Full Text Available Franscious Cummings Energy and Processes Materials Science and Manufacturing Council for Scientific and Industrial Research P.O. Box 395 Pretoria 0001, South Africa 13 November 2009 © CSIR 2007 www.csir.co.za CONTENT head2right...Background head2rightCSIR Dye Solar Cell Research head2rightCollaborations and Links head2rightAcknowledgements © CSIR 2007 www.csir.co.za BACKGROUND head2rightSA is dry: Annual rainfall average of 450 mm compared with a world average...

  6. Resonance energy transfer: Dye to metal nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wari, M. N.; Pujar, G. H.; Inamdar, S. R., E-mail: him-lax3@yahoo.com [Laser Spectroscopy Programme, Department of Physics, Karnatak University, Dharwad-580003 (India)

    2015-06-24

    In the present study, surface energy transfer (SET) from Coumarin 540A (C540 A) to Gold nanoparticle (Au) is demonstrated. The observed results show pronounced effect on the photoluminescence intensity and shortening of the lifetime of Coumarin 540A upon interaction with the spherical gold nanoparticle, also there are measured effects on radiative rate of the dye. Experimental results are analyzed with fluorescence resonance energy transfer (FRET) and SET theories. The results obtained from distance-dependent quenching provide experimental evidence that the efficiency curve slope and distance of quenching is best modeled by surface energy transfer process.

  7. Novel fluorescent dyes for single DNA molecule techniques.

    Science.gov (United States)

    Zarkov, Alexander; Vasilev, Aleksey; Deligeorgiev, Todor; Stoynov, Stoyno; Nedelcheva-Veleva, Marina

    2013-01-01

    To answer the demands of scientific and medical imaging issues, the family of nucleic acid fluorescent dyes is constantly enlarging. Most of the developed dyes reveal high qualities in bulk solution assays but are inefficient to produce a strong and sufficiently stable signal to enable the application of single-molecule techniques. Therefore, we tested 12 novel monomeric and homodimeric cyanine dyes for potential single DNA molecule imaging. Although their qualities in bulk solutions have already been described, nothing was known about their behavior on a single-molecule level. All 12 dyes demonstrated strong emission when intercalated into single DNA molecules and stretched on a silanized surface, which makes them the perfect choice for fluorescent microscopy imaging. A comparison of their fluorescence intensity and photostability with the most applicable dyes in single-molecule techniques, fluorescent dyes YOYO-1 and POPO-3, was carried out. They all exhibited a strong signal, comparable to that of YOYO-1. However, in contrast to YOYO-1, which is visualized under a green filter only, their emission permits red filter visualization. As their photostability highly exceeds that of similar spectrum POPO-3 dye, the studied dyes stand out as the best choice for a broad range of solid surface single-molecule applications when yellow to red DNA backbone fluorescence is needed.

  8. Novel Fluorescent Dyes for Single DNA Molecule Techniques

    Directory of Open Access Journals (Sweden)

    Alexander Zarkov

    2013-03-01

    Full Text Available To answer the demands of scientific and medical imaging issues, the family of nucleic acid fluorescent dyes is constantly enlarging. Most of the developed dyes reveal high qualities in bulk solution assays but are inefficient to produce a strong and sufficiently stable signal to enable the application of single-molecule techniques. Therefore, we tested 12 novel monomeric and homodimeric cyanine dyes for potential single DNA molecule imaging. Although their qualities in bulk solutions have already been described, nothing was known about their behavior on a single-molecule level. All 12 dyes demonstrated strong emission when intercalated into single DNA molecules and stretched on a silanized surface, which makes them the perfect choice for fluorescent microscopy imaging. A comparison of their fluorescence intensity and photostability with the most applicable dyes in single-molecule techniques, fluorescent dyes YOYO-1 and POPO-3, was carried out. They all exhibited a strong signal, comparable to that of YOYO-1. However, in contrast to YOYO-1, which is visualized under a green filter only, their emission permits red filter visualization. As their photostability highly exceeds that of similar spectrum POPO-3 dye, the studied dyes stand out as the best choice for a broad range of solid surface single-molecule applications when yellow to red DNA backbone fluorescence is needed.

  9. Decolorization of irgalite dye by immobilized Pseuodomonas putida ...

    African Journals Online (AJOL)

    A carbon sorbent derived from an agriculture waste, mustard straw was applied to study the removal of irgalite dye from aqueous solution. Comparative study on adsorption and simultaneous adsorption and biodegradation (+) of irgalite dye using Pseuodomonas putida (MTCC 1194) with activated carbon prepared from ...

  10. utilisation of azo and triphenylmethane dyes as sole source of ...

    African Journals Online (AJOL)

    the treatment of dye wastewater. Key words: Bacillus sp, primary biodegradation, methyl orange, malachite green. INTRODUCTION. Synthetic dyes are extensively used in the textile, food, cosmetics, pharmaceutical, paper, leather, photographic and aquaculture industries (Schnick,. 1988; Chen et al., 1999). The main ...

  11. Photostability effect of silica nanoparticles encapsulated fluorescence dye

    Science.gov (United States)

    Ahmad, Atiqah; Zakaria, Nor Dyana; Razak, Khairunisak Abdul

    2017-12-01

    Fluorescence dyes are based on small organic molecules have become of interest in chemical biology and widely used for cell and intracellular imaging. However, fluorescence dyes have limitations such as photo bleaching, poor photochemical stability and has a short Stokes shift. It is less valuable for long-term cell tracking strategies and has very short lifetime. In order to overcome the problems, dye-incorporated nanomaterials become of interest. Nanomaterials encapsulation provides a protection layer around the fluorescence dye which improves the stability of fluorescence dye. In this study, silica nanoparticles encapsulated with 1,1%-dioctadecyl-3,3,3%,3%-tetramethylindocarbocyanine perchlorate (Dil) was successfully synthesised by using micelle entrapment method to investigate the effect of encapsulation of nanoparticles towards the properties of fluorescent dye. The synthesised nanoparticles (SiDil) was characterised by particle size analyser, Transmission Electron Microscopy (TEM), UV-Vis spectrometer and Fluorescent spectrometer. Observation using TEM showed spherical shape of nanoparticles with 53 nm diameter. Monodispersed and well nanoparticles distribution was confirmed by low polydispersity index of 0.063 obtained by particle size analyser. Furthermore, the photoluminescence properties of the SiDil were evaluated and compared with bare Dil dye. Both SiDil and bare Dil was radiated under 200 W of Halogen lamp for 60 minutes and the absorbance intensity was measured using UV-Vis spectrometer. The result showed more stable absorbance intensity for SiDil compared to bare Dil dye, which indicated that Si nanoparticles encapsulation improved the photostability property.

  12. A study of dyes sorption on biobased cryogels

    Energy Technology Data Exchange (ETDEWEB)

    Dobritoiu, Rodica; Patachia, Silvia, E-mail: st.patachia@unitbv.ro

    2013-11-15

    Three types of biopolymers based materials were synthesized and tested as adsorbents for the dyes from aqueous solutions. Blends based on poly (vinyl alcohol) [PVA] and scleroglucan [Scl], cellulose micro-fibres [cel] and zein, respectively, have been prepared by repeated freezing–thawing cycles. Methylene blue [MB] was selected as a model dye in order to evaluate the capacity of the prepared materials to remove the dyes from aqueous solutions. The effects of the initial dye concentration, contact time and the composition of materials on the kinetic and thermodynamic parameters of sorption were discussed. The pseudo-second-order kinetics was found to better fit the experimental data thus being able to consistently predict the amount of dye adsorbed over the entire sorption period. The sorption equilibrium data obey Freundlich isotherm. Sorption capacity was evaluated both by dye solution and cryogel analysis by using VIS spectrometry and image analysis with CIELAB system. The sorption of monomer or aggregated dye molecules was identified and correlated with the type and morphology of the gel. The highest efficiency in MB removal was obtained for Scl/PVA cryogels in 1:9 weight ratio (9.5279 mg/g MB for an initial concentration by 8 × 10{sup −5} mol/L in MB). These materials are suitable as sorbents for the advanced removal of dyes from waste water.

  13. Synthesis and characterization of textile azo dyes derivatives of methoxyphenols

    OpenAIRE

    Ferreira, Isabel C.F.R.; Queiroz, Maria João R.P.

    1999-01-01

    Azo dyes are used extensively in the textile and dyestuff industries and effluents from these industrial processes are usually resistant to biological treatment. Textile azo dyes with bioaccessible groups such as guaiacol (2-methoxyphenol) and 2,6--dimethoxyphenol, for lignin-degrading fungus were synthesized using aminobenzoic and aminosulfonic acids as diazocomponents.

  14. Aerobic decolourization of two reactive azo dyes under varying ...

    African Journals Online (AJOL)

    Bacillus cereus isolated from dye industrial waste, that is, effluent and soil samples was screened for its ability to decolourize two reactive azo dye – cibacron black PSG and cibacron red P4B under aerobic conditions at pH 7 and incubated at 35°C over a five day period. Different carbon and nitrogen sources were used for ...

  15. Biodegradation of textile Azo Dyes by Phanerochaete chrysosporium

    OpenAIRE

    Ferreira, Isabel C.F.R.; Santos, Isabel M.; Queiroz, Maria João R.P.; Lima, Nelson

    1998-01-01

    Azo dyes are used extensively in the textile and dyestuff industries and effluents from these industrial processes are usually resistant to biological treatment. Textile azo dyes with bioaccessible groups such as guaiacol and 2,6-dimethoxyphenol, for lignin-degrading fungus as P. chrysosporium were synthesised.

  16. Types of Hair Dye and Their Mechanisms of Action

    Directory of Open Access Journals (Sweden)

    Simone Aparecida da França

    2015-04-01

    Full Text Available Hair color change by dye application is a common procedure among women. Hair dyes are classified, according to color resistance, into temporary, semipermanent, demipermanent and permanent. The first two are based on molecules which are already colored. Temporary dyes act through dye deposition on cuticles, but semipermanent may penetrate a little into the cortex and so the color resists up to six washes. Demipermanent and permanent dyes are based on color precursors, called oxidation dyes, and the final shade is developed by their interactions with an oxidizing agent, but they differ from the alkalizing agent used. In oxidation systems, there is an intense diffusion of the molecules into the cortex, what promotes a longer color resistance. Dyes and color precursors present differences related to chromophore groups, hair fiber affinity, water solubility, and photo stability. The aim of this review is to discuss the differences among hair dye products available in the market and their action mechanisms, molecular structures, application methods, and some aspects of formulations.

  17. Antimicrobial effect of natural dyes on some pathogenic bacteria ...

    African Journals Online (AJOL)

    P. granatum dye was most effective against the test bacteria except E. coli and S. epidermidis. The textile material impregnated with four natural dyes and maximum inhibition rates (respectivelly, 80, 86, 52%) were obtained against B. subtilis of wool samples dyed with P. granatum, A. cepa and R. tinctorum while maximum ...

  18. Biotransformation of Food Dyes by Human Intestinal Bacteria ...

    African Journals Online (AJOL)

    Biotransformation of food dyes (Tartrazine and Quinoline yellow) by Streptococcus faecalis and Escherichia coli isolated from human intestinal microflora was investigated. Decolourisation of the media containing the dyes was used as an index of biotransformation. Biotransformation was higher under aerobic than under ...

  19. Sensitization to reactive textile dyes in patients with contact dermatitis.

    Science.gov (United States)

    Manzini, B M; Motolese, A; Conti, A; Ferdani, G; Seidenari, S

    1996-03-01

    Reactive dyes are used especially for colouring natural fibres (cotton, silk and wool) that are widely used in Western countries, particularly Italy, in the production of clothes. The aim of our study was to investigate sensitization to the most commonly used reactive textile dyes in patients undergoing patch tests, and to assess the clinical relevance of contact sensitization to these dyes. 1813 consecutive patients underwent patch tests with the GIRDCA standard series and an additional textile series of 12 reactive dyes. 18 of these patients were sensitized to reactive dyes (0.99%) (4 only to reactive dyes). The dyes most frequently responsible for positive patch tests were Red Cibacron CR and Violet Remazol 5R (respectively, 8 and 5 positivities). In 5 cases only was a history of intolerance to particular garments given; of 4 patch tests performed with pieces of garment, 2 were positive. In 1 occupationally-exposed patient, airborne contact dermatitis was suspected. Owing to the lack of up-to-date patch test series, some cases of allergic contact dermatitis from textile dyes are probably misdiagnosed: new colouring agents are continuously introduced to the market, so that a close relationship with textile industry is necessary to improve our diagnostic tools.

  20. Textile dyes and pigments as a source of dioxins

    Energy Technology Data Exchange (ETDEWEB)

    Bostjan, K.; Marechal, A.M. le [Faculty of Mechanical Engineering, Maribor (Slovenia); Voncina, E. [Environmental Protection Institute, Maribor (Slovenia); Brodnjak-Voncina, D. [Faculty of Chemistry and Chemical Engineering, Maribor (Slovenia)

    2004-09-15

    Synthesis of colorants represents a relatively large group of chemicals with complex synthesis processes. Over 7 x 10 ton of dyestuff is produced annually worldwide with more than 100,000 types of dyes and pigments. During synthesis of some colorants polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) can be formed. Dioxins are related to halogens, especially chlorine and bromine homologues are most toxic and persistent. About 40% of worldwide used colorants contain organically bounded chlorine. Further formations of PCDD/Fs can occur via dyeing and textile finishing processes with conditions favoured for the generation of PCDD/Fs (high temperatures, alkaline conditions, UV radiations or other radical starters). Relative small number of data is available for PCDD/Fs presence and contents in textile dyes and pigments. Known sources of PCDD/Fs are dioxazine dyes and pigments, produced from chloranil1. Chloranil is produced from chlorinated phenols and during the synthesis PCDD/Fs as by products are formed. In a sample of Ni-phthalocyanine dye higher congeners of PCDD/Fs were found in {mu}g/kg concentration level. In our work six samples of disperse dyes were analysed for PCDD/Fs content. In two disperse black dyes, a mixture of anthraquinone and azo-disperse dye, considerable level ({mu}g/kg) of PCDD/Fs was determined. The OCDD was the dominant compound. Distribution of dioxins and their fate during textile processes were further investigated.

  1. Synthesis and application of dyes derived from Schaeffer's acid on ...

    African Journals Online (AJOL)

    The effects of increasing temperature of heat-set at 90 seconds, auxiliary concentration and dyeing time respectively were also investigated. Exhaustion dyeing method was used in all the investigations. The results showed that as the heat-set time increased percentage exhaustion decreased, indicating that the nylon 6,6 ...

  2. Decolourisation of chemically different dyes by enzymes from spent ...

    African Journals Online (AJOL)

    Based on the effect of hydrogen peroxide on the rate of decolourisation of each dye, the dyes could be divided into two groups. From the results of the present study, it could be concluded that the enzymes extracted from the spent compost of P. sajor-caju offers an economical advantage of obtaining industrially important ...

  3. Comparative studies on dyeing rate migration and wash fastness ...

    African Journals Online (AJOL)

    Migration and diffusion properties of synthesized azo dyes from 2-aminothiazole derivatives applied on commercial grade undyed cellulose acetate (CA) and cellulose triacetate (CTA) were investigated using dyeing conditions of 2% on weight of fabric (owf), 50:1 liquor ratio and subjected to ISO3 and ISO4 standard wash ...

  4. An Interdisciplinary Experiment: Azo-Dye Metabolism by "Staphylococcus Aureus"

    Science.gov (United States)

    Brocklesby, Kayleigh; Smith, Robert; Sharp, Duncan

    2012-01-01

    An interdisciplinary and engaging practical is detailed which offers great versatility in the study of a qualitative and quantitative metabolism of azo-dyes by "Staphylococcus aureus". This practical has broad scope for adaptation in the number and depth of variables to allow a focused practical experiment or small research project. Azo-dyes are…

  5. Suppression of cucurbit scab on cucumber leaves by photodynamic dyes

    Science.gov (United States)

    The goal of this study was to test the ability of the photodynamic dyes bengal rose, toluidine blue, and methylene blue, to protect systemically cucumber plants from cucurbit scab. At the stage of one true leaf, water or aqueous solutions of the dyes were applied to the leaf as droplets. When the se...

  6. Toxic textile dyes accumulate in wild European eel Anguilla anguilla.

    Science.gov (United States)

    Belpaire, Claude; Reyns, Tim; Geeraerts, Caroline; Van Loco, Joris

    2015-11-01

    Dyes are used to stain inks, paints, textile, paper, leather and household products. They are omnipresent, some are toxic and may threaten our environment, especially aquatic ecosystems. The presence of residues of sixteen dyes (triarylmethanes, xanthenes, phenothiazines and phenoxazines) and their metabolites was analyzed in muscle tissue samples of individual yellow-phased European eels (Anguilla anguilla) from 91 locations in Belgian rivers, canals and lakes sampled between 2000 and 2009 using ultra performance liquid chromatography-tandem mass spectrometry. Eel was contaminated by dyes in 77% of the sites. Malachite Green, Crystal Violet and Brilliant Green were present in 25-58% of the samples. Dye occurrence was related to the distribution of textile and dye production industries. This field study is the first large-scale survey to document the occurrence of artificial dyes in wildlife. Considering the annual amounts of dyes produced worldwide and the unintentional spillage during their use, our observations warrant additional research in other parts of the world. The presence of these highly toxic dyes in the European eel may form an additional threat to this critically endangered species. The contaminated eels should be considered as not suitable for consumption. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Electronic structure of Fe- vs. Ru-based dye molecules

    DEFF Research Database (Denmark)

    Johnson, Phillip S.; Cook, Peter L.; Zegkinoglou, Ioannis

    2013-01-01

    In order to explore whether Ru can be replaced by inexpensive Fe in dye molecules for solar cells, the differences in the electronic structure of Fe- and Ru-based dyes are investigated by X-ray absorption spectroscopy and first-principles calculations. Molecules with the metal in a sixfold...

  8. Photophysical and laser characteristics of pyrromethene 567 dye ...

    Indian Academy of Sciences (India)

    2015-11-27

    PM567) and rhodamine 6G (RH6G) dye was investigated using a home-made GIG- configured dye laser, excited by the second-harmonic radiation (at 532 nm) of a pulsed Nd:YAG laser. Higher laser efficiency was observed with ...

  9. The Chemistry of Vat Dyes. Palette of Color Monograph Series.

    Science.gov (United States)

    Epp, Dianne N.

    From prehistoric times people have been fascinated with color; from cave paintings to the latest computers, color has been a constant companion. Textiles are made more beautiful by the alteration or application of colorants. This teaching resource investigates vat dyes, a colorant class which includes the oldest dyes known as well as important…

  10. Characteristics and dyes biodegradation potential of crude lignolytic ...

    African Journals Online (AJOL)

    Characteristics and dyes biodegradation potential of crude lignolytic enzymes from white-rot fungus crepidotus variabilis isolated in coastal Tanzania. ... Also, they could remove up to 58% and 92% color from raw textile effluent and aromatic dyes, respectively, after 14 days of incubation at 30ºC and pH 4.5. Desalted and ...

  11. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal complex...

  12. Structural and spectral properties of 4-phenoxyphthalonitrile dye ...

    Indian Academy of Sciences (India)

    Keywords. Electronic structure; absorption spectrum; dye sensitizer; density functional theory; vibrational spectra. 1. Introduction. The new technologies for direct solar energy conversion have gained more attention in the last few years. In parti- cular, Dye sensitized solar cells (DSSCs) are promising in terms of efficiency and ...

  13. Structural and spectral properties of 4-phenoxyphthalonitrile dye ...

    Indian Academy of Sciences (India)

    Structural and spectral properties of 4-phenoxyphthalonitrile dye sensitizer for solar cell applications ... electronic structures, polarizabilities and hyperpolarizabilities of organic dye sensitizer 4-phenoxyphthalonitrile was studied based on ab initio HF and density functional theory (DFT) using the hybrid functional B3LYP.

  14. Rose bengal-sensitized nanocrystalline ceria photoanode for dye ...

    Indian Academy of Sciences (India)

    Abstract. For efficient charge injection and transportation, wide bandgap nanostructured metal oxide semicon- ductors with dye adsorption surface and higher electron mobility are essential properties for photoanode in dye- sensitized solar cells (DSSCs). TiO2-based DSSCs are well established and so far have ...

  15. Removal of basic dyes from solution using coconut shell charcoal

    Directory of Open Access Journals (Sweden)

    Srisorrachatr Siriwan

    2017-01-01

    Full Text Available This research aims to use agricultural waste as an adsorbent for dye removal from textile wastewater. Coconut shell charcoal (CSC, an agricultural waste, was used as dye adsorbent whilst basic yellow13 (BY13 and basic red14 (BR14 were used as representative dye used in textile manufactory. The removal of BY13 and BR14 from aqueous solution by CSC was investigated in batch adsorption at room temperature. Two parameters investigated in this research were pH of dyes solution; pH 2, 7, and 11, and particle size of adsorbents; 510-700 μm and 1000-2000 μm. The adsorption model, Langmuir and Freundlich were also examined. It was found that by CSC, BY13 and BR14 had maximum removal percentage of 23.6 and 55.7 at pH 11. Size of adsorbent had also shown the effect on dye removal, i.e.; increasing size with decreasing removal capability. The dye removal experimental data were fitted to Langmuir adsorption model for both dyes with maximum adsorption capacity (qm for BY13 and BR14 of 19.76 and 22.93 mg/g, respectively. It can be implied that the adsorption is monolayer. It can conclude that CSC can be used as adsorbent for basic dye removal from aqueous solution.

  16. Rate equation simulation of temporal characteristics of a pulsed dye ...

    Indian Academy of Sciences (India)

    Laser & Plasma Technology Division, Bhabha Atomic Research Centre,. Mumbai 400 085, India ... To design and build high-power, pulsed dye laser MOPA systems, it is necessary to have a detailed knowledge .... qualitative and reasonably good quantitative agreement with experimental results on two separate dye laser ...

  17. Adsorption thermodynamics of some basic dyes uptake from ...

    African Journals Online (AJOL)

    The efficiency of Albizia lebbeck shell for the adsorption of auramine yellow (AY), basic malachite green (BMG) and basic violet (BV) dyes from aqueous solution has been studied in a batch system. The effects of contact time, adsorbent dosage, initial dye concentration, solution pH and temperature have been investigated ...

  18. BOXTO as a real-time thermal cycling reporter dye

    Indian Academy of Sciences (India)

    PRAKASH

    BOXTO as a real-time thermal cycling reporter dye. ASHRAF I AHMAD. Department of Chemical and Biological Engineering-Molecular Biotechnology, Chalmers University of Technology,. 405 30 Göteborg, Sweden. (Fax, 46 31 773 3910; Email, ashraf.ahmad@molbiotech.chalmers.se). The unsymmetrical cyanine dyes ...

  19. Orientation control of dye molecules in a liquid crystal.

    Science.gov (United States)

    Urisu, T; Kajiyama, K; Mizushima, Y

    1978-08-01

    Laser dye molecules (coumarin 6) were dissolved in a nematic liquid crystal MBBA + BBCA. Great changes in polarization and fluorescence vs applied voltage were found as well as a change in dielectric constant. Molecular orientation of the liquid crystal under the electric field and association of the dye molecules are identified as having the greatest effect on the fluorescence intensity.

  20. Fixed Drug Eruption due to Achiote Dye.

    Science.gov (United States)

    Tattersall, Ian; Reddy, Bobby Y

    2016-01-01

    Fixed drug eruption (FDE) is a localized type IV sensitivity reaction to a systemically introduced allergen. It usually occurs as a result of new medication, making identification and avoidance of the trigger medication straightforward; however, in a rare subset of cases no pharmacological source is identified. In such cases, the causative agent is often a food or food additive. In this report we describe a case of a FDE in a 12-year-old girl recently immigrated to the United States from Ecuador who had no medication exposure over the course of her illness. Through an exhaustive patient history and literature review, we were able to hypothesize that her presentation was caused by a dietary change of the natural achiote dye used in the preparation of yellow rice to a locally available commercial dye mix containing tartrazine, or Yellow 5, which has previously been implicated in both systemic hypersensitivity reactions and specifically in FDE. This report adds to the small body of available literature on non-pharmacological fixed hypersensitivity eruptions and illustrates an effective approach to the management of such a presentation when history is not immediately revealing.

  1. Adsorption of azo dyes on polymer materials

    Directory of Open Access Journals (Sweden)

    Panić Vesna V.

    2013-01-01

    Full Text Available The use of polymeric adsorbents for the removal of azo dyes from solution has been reviewed. Adsorption techniques are widely used to remove certain classes of pollutants from waters, especially those which are not easily biodegradable. The removal of azo dyes as pollutants from wastewaters of textile, paper, printing, leather, pharmaceutical and other industries has been addressed by the researchers. The wider use of already available adsorbents is restricted due to their high costs which lead to investigation and development of new materials that can be cheaper, eficient and easy regenerated. The aim of this article is to present to the readers the widespread investigations in recent years of synthetic and natural polymers as adsorbents and potential replacement of conventional adsorbents. This review presents only the data obtained using raw, hydrogel, grafted and crosslinked forms of synthetic and nature based polymers, and the discussion is limited to these polymer-based materials and their adsorption properties. [Projekat Ministarstva nauke Republike Srbije, br. 43009 i br. 172062.

  2. Fixed Drug Eruption due to Achiote Dye

    Science.gov (United States)

    Tattersall, Ian; Reddy, Bobby Y.

    2016-01-01

    Fixed drug eruption (FDE) is a localized type IV sensitivity reaction to a systemically introduced allergen. It usually occurs as a result of new medication, making identification and avoidance of the trigger medication straightforward; however, in a rare subset of cases no pharmacological source is identified. In such cases, the causative agent is often a food or food additive. In this report we describe a case of a FDE in a 12-year-old girl recently immigrated to the United States from Ecuador who had no medication exposure over the course of her illness. Through an exhaustive patient history and literature review, we were able to hypothesize that her presentation was caused by a dietary change of the natural achiote dye used in the preparation of yellow rice to a locally available commercial dye mix containing tartrazine, or Yellow 5, which has previously been implicated in both systemic hypersensitivity reactions and specifically in FDE. This report adds to the small body of available literature on non-pharmacological fixed hypersensitivity eruptions and illustrates an effective approach to the management of such a presentation when history is not immediately revealing. PMID:26933409

  3. Natural adsorbents of dyes from aqueous solution

    Science.gov (United States)

    Rahmani, Meryem; El Hajjaji, souad; Dahchour, Abdelmalek; El M'Rabet, Mohammadine

    2017-04-01

    Contamination of natural waters is a current environmental problem and lot of work has been done to find methods for its, prevention and remediation such as ionic exchange, adsorption on active carbon, filtration, electrolysis, biodegradation …etc. Adsorption is one of the most applied methods according to its effectiveness and easy management. Some adsorbents with good properties such as active alumina, zeolites, crop residues … etc, are suitable to substitute usual active carbon. This study aimed at the removal of dyes using oil shale as natural support, and its optimization by factorial experiment. Three factors were considered namly:pollutant concentration, pH and weight of the adsorbent. Tests have been performed with cationic and anionic dyes. Experimental results show that pseudo-first-order kinetic model provided the best fit to the experimental data for the adsorption by the oil shale. Langmuir, Freundlich and Temkin isotherm models were tested to fit experimental data, the adsorption equilibrium was well described by Freundlich isotherm for methylorange and Temkin for methyl blue. Analysis were completed by oil shale characterization educing XRD, IR, XRF techniques, and cationic exchange capacity.

  4. Fixed Drug Eruption due to Achiote Dye

    Directory of Open Access Journals (Sweden)

    Ian Tattersall

    2016-01-01

    Full Text Available Fixed drug eruption (FDE is a localized type IV sensitivity reaction to a systemically introduced allergen. It usually occurs as a result of new medication, making identification and avoidance of the trigger medication straightforward; however, in a rare subset of cases no pharmacological source is identified. In such cases, the causative agent is often a food or food additive. In this report we describe a case of a FDE in a 12-year-old girl recently immigrated to the United States from Ecuador who had no medication exposure over the course of her illness. Through an exhaustive patient history and literature review, we were able to hypothesize that her presentation was caused by a dietary change of the natural achiote dye used in the preparation of yellow rice to a locally available commercial dye mix containing tartrazine, or Yellow 5, which has previously been implicated in both systemic hypersensitivity reactions and specifically in FDE. This report adds to the small body of available literature on non-pharmacological fixed hypersensitivity eruptions and illustrates an effective approach to the management of such a presentation when history is not immediately revealing.

  5. Solar efficiency of a photo catalytic nonwoven: dye removal applications

    Energy Technology Data Exchange (ETDEWEB)

    Guillard, C.; Disdier, J.; Herrmann, J. M.; Monnet, C.; Dussaud, J.; Malato, S.; Blanco, J.

    2003-07-01

    A specially designed titania photo catalyst was prepared by coating Ahlstrom non-woven paper, used as a flexible photo catalytic support, with Millennium anatase PC50 and PC500 at different mass coatings. Several types of reactants were treated: formetanate (pesticide), Remazole (azo-dye), Amaranth (azo-dye) and Methylene Blue (model dye). Supported catalysts installed in a new solar photo reactor (STEP) were compared to the well-known CPCs working with slurries (0.5 g/L) of the same catalysts. Efficiency of both photo catalytic system was very similar for formetanate removal but not for dye degradation, for which the CPC was more efficient. Solar UV light adsorption by dyes is proposed as the reason for these results. (Author) 12 refs.

  6. Plant waste materials from restaurants as the adsorbents for dyes

    Directory of Open Access Journals (Sweden)

    Pavlović Marija D.

    2015-01-01

    Full Text Available This paper has demonstrated the valorization of inexpensive and readily available restaurant waste containing most consumed food and beverage residues as adsorbents for methylene blue dye. Coffee, tea, lettuce and citrus waste have been utilized without any pre-treatment, thus the adsorption capacities and dye removal efficiency were determined. Coffee waste showed highest adsorbent capacity, followed by tea, lettuce and citrus waste. The dye removal was more effective as dye concentration increases from 5 up to 60 mg/L. The favorable results obtained for lettuce waste have been especially encouraged, as this material has not been commonly employed for sorption purposes. Equilibrium data fitted very well in a Freundlich isotherm model, whereas pseudo-second-order kinetic model describes the process behavior. Restaurant waste performed rapid dye removal at no cost, so it can be adopted and widely used in industries for contaminated water treatment.

  7. Screening of freshwater fungi for decolorizing multiple synthetic dyes.

    Science.gov (United States)

    Yang, Panpan; Shi, Wenxiao; Wang, Hongkai; Liu, Hongmei

    The biodegradation of synthetic dyes by fungi is emerging as an effective and promising approach. In the present study, freshwater fungal strains isolated from submerged woods were screened for the decolorization of 7 synthetic dyes. Subsequently, 13 isolates with high decolorization capability were assessed in a liquid system; they belonged to 9 different fungal species. Several strains exhibited a highly effective decolorization of multiple types of dyes. New absorbance peaks appeared after the treatment with 3 fungal strains, which suggests that a biotransformation process occurred through fungal biodegradation. These results showed the unexploited and valuable capability of freshwater fungi for the treatment of dye-containing effluents. The ability of certain fungi to decolorize dyes is reported here for the first time. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  8. Spectrally resolved visualization of fluorescent dyes permeating into skin

    Science.gov (United States)

    Maeder, Ulf; Bergmann, Thorsten; Beer, Sebastian; Burg, Jan Michael; Schmidts, Thomas; Runkel, Frank; Fiebich, Martin

    2012-03-01

    We present a spectrally resolved confocal imaging approach to qualitatively asses the overall uptake and the penetration depth of fluorescent dyes into biological tissue. We use a confocal microscope with a spectral resolution of 5 nm to measure porcine skin tissue after performing a Franz-Diffusion experiment with a submicron emulsion enriched with the fluorescent dye Nile Red. The evaluation uses linear unmixing of the dye and the tissue autofluorescence spectra. The results are combined with a manual segmentation of the skin's epidermis and dermis layers to assess the penetration behavior additionally to the overall uptake. The diffusion experiments, performed for 3h and 24h, show a 3-fold increased dye uptake in the epidermis and dermis for the 24h samples. As the method is based on spectral information it does not face the problem of superimposed dye and tissue spectra and therefore is more precise compared to intensity based evaluation methods.

  9. Vibrational spectroscopy of photosensitizer dyes for organic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Perez Leon, C.

    2005-11-18

    Ruthenium(II) complexes containing polypyridyl ligands are intensely investigated as potential photosensitizers in organic solar cells. Of particular interest is their use in dye-sensitized solar cells based on nanocrystalline films of TiO{sub 2}. Functional groups of the dye allow for efficient anchoring on the semiconductor surface and promote the electronic communication between the donor orbital of the dye and the conduction band of the semiconductor. In the present work a new dye, [Ru(dcbpyH{sub 2}){sub 2}(bpy-TPA{sub 2})](PF6{sub )2}, and the well known (Bu{sub 4}N){sub 2}[Ru(dcbpyH){sub 2}(NCS){sub 2}] complex were spectroscopically characterized. The electronic transitions of both dyes showed solvatochromic shifts due to specific interactions of the ligands with the solvent molecules. The surface-enhanced Raman (SER) spectra of the dyes dissolved in water, ethanol, and acetonitrile were measured in silver and gold colloidal solutions. The results demonstrate that the dyes were adsorbed on the metallic nanoparticles in different ways for different solvents. It was also found that in the gold colloid, the aqueous solutions of both dyes did not produce any SERS signal, whereas in ethanolic solution the SERS effect was very weak. Deprotonation, H-bonding, and donor-acceptor interactions seem to determine these different behaviors. Our results indicate the important role of the charge transfer mechanism in SERS. The adsorption of the dye on two different TiO{sub 2} substrates, anatase paste films and anatase nanopowder, was also studied to clarify the role of the carboxylate groups in the anchoring process of the dyes on the semiconductor surface. The recorded spectra indicate a strong dependence of the anchoring configuration on the morphology of the semiconductor. (orig.)

  10. Azo-hydrazone tautomerism of aryl azo pyridone dyes

    Directory of Open Access Journals (Sweden)

    Mirković Jelena M.

    2013-01-01

    Full Text Available In the last three or four decades disperse dyes derived from pyridones (in particular azo pyridone dyes have gained in importance, and are widely used in various fields. These compounds have excellent coloration properties, and are suitable for the dyeing of polyester fabrics. Basic features of these dyes are simplicity of their synthesis by diazotation and azo coupling. They generally have high molar extinction coefficient with medium to high light and wet fastness. The absorption maxima of these dyes show their visible absorption wavelength ranging from yellow to orange, which can be attributed to poorly delocalized electrons in the pyridone ring. However, there are several dyes with deep colors such as red or violet. Pyridone dyes with alkyl and aryl groups in ortho position to azo group show 2-pyridone/2-hydroxypyridine tautomerism, while those containing OH and NHR groups conjugated with the azo group show azo-hydrazone tautomerism. Determining azo-hydrazone tautomerism could be therefore interesting, since the tautomers have different physico-chemical properties and most importantly different coloration. The literature on azo-hydrazone tautomerism, determination of equilibrium position, and investigation of substituent and solvent influence on tautomerism has been summarized in the presented review. The general conclusion is that the equilibrium between two tautomers is influenced by the structure of the compounds and by the solvents used. The tautomeric behavior patterns of the arylazo pyridone dyes in the reviewed literature has been studied using various instrumental techniques, including FT-IR, UV-vis, and NMR spectroscopy. The quantum chemical calculations related to the azo-hydrazon tautomerism have also been included. A large number of pyridone dyes exist in hydrazone form in solid state, while in solvents there is a mixture of tautomers. In addition, the X-ray single-crystal diffraction data analysis of some commercial pyridone

  11. Anaerobic/aerobic treatment of selected azo dyes in wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Seshadri, S.; Bishop, P.L. (Univ. of Cincinnati, OH (United States). Dept. of Civil and Environmental Engineering); Agha, A.M. (Univ. of Aleppo (Syrian Arab Republic). Faculty of Civil Engineering)

    1994-01-01

    Azo dyes represent the largest class of dyes in use today. Current environmental concern with these dyes revolves around the potential carcinogenic health risk presented by these dyes or their intermediate biodegradation products when exposed to microflora in the human digestive tract. These dyes may build up in the environment, since many wastewater treatment plants allow these dyes to pass through the system virtually untreated. The initial step in the degradation of these dyes is the cleavage of the Azo bond. This cleavage is often impossible under aerobic conditions, but has been readily demonstrated under anaerobic conditions. The focus of the study was to determine the feasibility of using an anaerobic fluidized-bed reactor to accomplish this cleavage. The effects of typical process variables such as hydraulic retention time (HRT), influent dye concentration levels, and degree of bed fluidization on removal efficiencies were also studied. The four dyes selected for this study were Acid-Orange 7, Acid-Orange 8, Acid-Orange 10, and Acid-Red 14. The effectiveness of using a bench-scale-activated sludge reactor as a sequenced second stage was also examined. Results indicate that nearly complete cleavage of the Azo bond is easily accomplished for each of the four dyes under hydraulic retention times of either 12 or 24 h. Initial results indicate, though, that aromatic amine by-products remain. The sequenced second stage was able to remove the remaining Chemical Oxygen Demand (COD) load to acceptable levels. Work is presently underway to determine the face of the anaerobic by-products in the aerobic second stage.

  12. DYEING SILK FABRICS WITH STINK BEAN POD (PARKIA SPECIOSA HASSK. NATURAL DYE IN THE COLOR FASTNESS AND UV PROTECTION

    Directory of Open Access Journals (Sweden)

    M. MASAE

    2017-07-01

    Full Text Available This paper describes natural dye extracted from stink bean pod (Parkia speciosa Hassk. which was dyed on the silk fabric. The mordants as aluminum potassium sulfate, iron chloride, sodium hydroxide and mud were used to dye fabric using three different dyeing methods: pre-mordanting, meta-mordanting and post-mordanting. The color fastness to washing, water, perspiration, light and crocking of the dyed samples was determined according to AATCC test methods. In this study the UV-protection properties on silk fabrics were investigated. The chemical functional groups of the dyes were characterized by Fourier transform infrared spectroscopy (FTIR. The results revealed that the dyeing silk fabrics with stink beans pod were fair to good fastness to washing and crocking and very poor to poor light fastness with the exception of samples mordanted with iron chloride. The water and perspiration fastness ratings were fair to good. Silk fabrics mordanted with iron chloride and dyed with stink bean usually showed good UV-protection levels even if undyed. These extracts gave polyphenolic, betalain dye and chlorophyll content. Therefore, it was suggested that stink bean pod has the potential in producing functional dyes that could be imparted into the silk dyeing natural colorant system.

  13. Photoelectric characterization of fabricated dye-sensitized solar cell using dye extracted from red Siahkooti fruit as natural sensitizer.

    Science.gov (United States)

    Mozaffari, Sayed Ahmad; Saeidi, Mahsa; Rahmanian, Reza

    2015-05-05

    Natural dye extracted from Siahkooti fruit with/without purification by solid phase extraction (SPE) technique was used in the fabrication of DSSC as natural sensitizer. The UV-Vis absorption spectroscopy and Fourier transform infrared (FTIR) were employed to indicate the presence of anthocyanins in the fruit of red Siahkooti. The photoelectrochemical performance and the efficiency of assembled DSSC using Siahkooti fruit dye extract were evaluated and efficiency enhancement was obtained by a preliminary purification of extracted dye. The efficiency and fill factor of the DSSC using purified Siahkooti fruit dye were 0.32% and 0.73%, respectively. The results successfully showed that the DSSC, using Siahkooti fruit extract as a dye sensitizer, is useful for the preparation of environmentally friendly, low-cost, renewable and clean sources of energy. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Improved Reactive Dye-fixation in Pad-Steam Process of Dyeing Cotton Fabric Using Tetrasodium N, NBiscarboxylatomethyl- L-Glutamate

    Directory of Open Access Journals (Sweden)

    Awais Khatri

    2012-04-01

    Full Text Available Pad steam process of dyeing cotton with reactive dyes is known to give lower levels of dye-fixation on the fiber because of excessive dye-hydrolysis. This research presents improved reactive dye-fixation in padsteam process of dyeing cotton found in an effort of using biodegradable organic salts to improve the effluent quality. The CI Reactive Blue 250, a bissulphatoethylsulphone dye and the Tetrasodium N, Nbiscarboxylatomethyl- L-Glutamate, a biodegradable organic salt, were used. The new dye-bath formulation using the organic salt gave more than 90% dye-fixation. Traditional pad-steam process of dyeing cotton with reactive dyes requires the use of inorganic electrolyte, sodium-chloride, and alkali, sodium-carbonate, to ensure effective dye consumption and fixation. These inorganic chemicals when drained generate heavy contents of dissolved solids and oxygen demand in the effluent leading to environmental pollution. Thus, Tetrasodium N, N-biscarboxylatomethyl-L-Glutamate was used in place of inorganic electrolyte and alkali to improve effluent quality. A significant increase in dye-fixation and ultimate color-yield was obtained with same colorfastness properties of the dyed fabric comparing to the traditional pad-steam dye-bath formulation.

  15. Fluorescent vinyl and styryl coumarins: A comprehensive DFT study ...

    Indian Academy of Sciences (India)

    Kiran Avhad

    2017-11-14

    Nov 14, 2017 ... Nakai H, Vreven T, Montgomery Jr J A, Peralta J E,. Ogliaro F, Bearpark M, Heyd J J, Brothers E, Kudin K. N, Staroverov V N, Keith T, Kobayashi R, Normand J,. Raghavachari K, Rendell A, Burant J C, Iyengar S S,. Tomasi J, Cossi M, Rega N, Millam J M, Klene M, Knox. J E, Cross J B, Bakken V, Adamo C, ...

  16. Selective labelling of cell-surface proteins using CyDye DIGE Fluor minimal dyes.

    Science.gov (United States)

    Hagner-McWhirter, Asa; Winkvist, Maria; Bourin, Stephanie; Marouga, Rita

    2008-11-26

    Surface proteins are central to the cell's ability to react to its environment and to interact with neighboring cells. They are known to be inducers of almost all intracellular signaling. Moreover, they play an important role in environmental adaptation and drug treatment, and are often involved in disease pathogenesis and pathology (1). Protein-protein interactions are intrinsic to signaling pathways, and to gain more insight in these complex biological processes, sensitive and reliable methods are needed for studying cell surface proteins. Two-dimensional (2-D) electrophoresis is used extensively for detection of biomarkers and other targets in complex protein samples to study differential changes. Cell surface proteins, partly due to their low abundance (1 2% of cellular proteins), are difficult to detect in a 2-D gel without fractionation or some other type of enrichment. They are also often poorly represented in 2-D gels due to their hydrophobic nature and high molecular weight (2). In this study, we present a new protocol for intact cells using CyDye DIGE Fluor minimal dyes for specific labeling and detection of this important group of proteins. The results showed specific labeling of a large number of cell surface proteins with minimal labeling of intracellular proteins. This protocol is rapid, simple to use, and all three CyDye DIGE Fluor minimal dyes (Cy 2, Cy 3 and Cy 5) can be used to label cell-surface proteins. These features allow for multiplexing using the 2-D Fluorescence Difference Gel Electrophoresis (2-D DIGE) with Ettan DIGE technology and analysis of protein expression changes using DeCyder 2-D Differential Analysis Software. The level of cell-surface proteins was followed during serum starvation of CHO cells for various lengths of time (see Table 1). Small changes in abundance were detected with high accuracy, and results are supported by defined statistical methods.

  17. FLUX OF IONIC DYES ACROSS MICRONEEDLE-TREATED SKIN: EFFECT OF DYE MOLECULAR CHARACTERISTICS

    Science.gov (United States)

    Gomaa, Yasmine A.; Garland, Martin J.; McInnes, Fiona; Donnelly, Ryan F.; El-Khordagui, Labiba K.; Wilson, Clive

    2014-01-01

    Drug flux across microneedle (MN)-treated skin is influenced by the characteristics of the MN array, microconduits and drug molecules in addition to the overall diffusional resistance of microconduits and viable tissue. Relative implication of these factors has not been fully explored. In the present study, the in vitro permeation of a series of six structurally related ionic xanthene dyes with different molecular weights (MW) and chemical substituents, across polymer MN-pretreated full thickness porcine skin was investigated in relation of their molecular characteristics. Phosphate buffer saline pH 7.4, the medium used in skin permeation experiments, was used to determine the equilibrium solubility of the dyes and their partition coefficient both in the isotropic n-octanol/ aqueous system and porcine skin/ aqueous system. Additionally, dissociation constants were determined potentiometrically. Results indicated that for rhodamine dyes, skin permeation of the zwitterionic form which predominates at physiological pH, was significantly reduced by an increase in MW, the presence of the chemically reactive isothiocyanate substituent reported to interact with stratum corneum proteins and the skin thickness. These factors were generally shown to override aqueous solubility, an important determinant of drug diffusion in an aqueous milieu. Findings provided more insight into the mechanism of drug permeation across MN-treated skin, of importance to both the design of MN-based transdermal drug delivery systems and in vitro skin permeation research. PMID:22960319

  18. Antibacterial Dyeing of Wool with Natural Cationic Dye Using Metal Mordants

    Directory of Open Access Journals (Sweden)

    Aminoddin HAJI

    2012-09-01

    Full Text Available In this study, Berberine colorant extracted from berberis vulgaris root was applied on wool fiber using alum (aluminum potassium sulfate, copper sulfate and potassium dichromate as mordant. The effect of treatment variables such as amount of mordant, time and temperature on the color strength of dyed fibers was examined. The fastness properties of dyed wool against washing, light and wet rubbing were evaluated. the use of metal mordants increased the color strength of the dyed goods. Increase in dyeing time and temperature caused deeper shades. All mordants, increased the rub fastness and wash fastness of dyed samples, but the light fastness was increased except in case of alum. Berberine is a cationic dye and because of it's quaternary ammonium structure can act as an antibacterial agent. So, dyed samples were tested for antibacterial activity using AATCC test method 100-2004. The dyed wool represented a high level of antibacterial activity. The extract of the berberis vulgaris can be considered as a natural dye of acceptable fastness properties together with excellent antibacterial activity for woolen textiles.DOI: http://dx.doi.org/10.5755/j01.ms.18.3.2437

  19. Making cancer visible--Dyes in surgical oncology.

    Science.gov (United States)

    Yap, Kiryu K; Neuhaus, Susan J

    2016-03-01

    Dyes share an intricate relationship with oncology. Dyes can cause cancer as chemical carcinogens, but can also be harnessed against cancer when used as diagnostic and therapeutic agents. Histopathology, imaging, and newer molecular diagnostics all rely on dyes, and their use in sentinel lymph node biopsies and intra-operative imaging has helped drive a paradigm shift in cancer surgery towards minimally-invasive and organ sparing approaches with enhanced resection accuracy. As therapeutic agents, the cytotoxicity of specific dyes can be employed in direct chemo-ablation or in photodynamic therapy. The same agent can have dual functionalities in cancer detection and treatment, in a novel field known as theranostics. This is facilitated by newer generation dyes conjugated with tumour-targeting probes such as antibodies, and these bio-conjugate agents can also incorporate nanotechnology or radio-isotopes. Further advances will be closely aligned with our increasing understanding of molecular oncology, and will form a new generation of cancer detection and treatment agents that promote precision medicine for cancer. Dyes and their roles have evolved and been reinvented, but they remain relevant as ever. This review explores the fascinating history of dyes, and their place in the state-of-the-art of oncology. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  20. Detoxification of azo dyes by bacterial oxidoreductase enzymes.

    Science.gov (United States)

    Mahmood, Shahid; Khalid, Azeem; Arshad, Muhammad; Mahmood, Tariq; Crowley, David E

    2016-08-01

    Azo dyes and their intermediate degradation products are common contaminants of soil and groundwater in developing countries where textile and leather dye products are produced. The toxicity of azo dyes is primarily associated with their molecular structure, substitution groups and reactivity. To avoid contamination of natural resources and to minimize risk to human health, this wastewater requires treatment in an environmentally safe manner. This manuscript critically reviews biological treatment systems and the role of bacterial reductive and oxidative enzymes/processes in the bioremediation of dye-polluted wastewaters. Many studies have shown that a variety of culturable bacteria have efficient enzymatic systems that can carry out complete mineralization of dye chemicals and their metabolites (aromatic compounds) over a wide range of environmental conditions. Complete mineralization of azo dyes generally involves a two-step process requiring initial anaerobic treatment for decolorization, followed by an oxidative process that results in degradation of the toxic intermediates that are formed during the first step. Molecular studies have revealed that the first reductive process can be carried out by two classes of enzymes involving flavin-dependent and flavin-free azoreductases under anaerobic or low oxygen conditions. The second step that is carried out by oxidative enzymes that primarily involves broad specificity peroxidases, laccases and tyrosinases. This review focuses, in particular, on the characterization of these enzymes with respect to their enzyme kinetics and the environmental conditions that are necessary for bioreactor systems to treat azo dyes contained in wastewater.

  1. Toxicological significance of azo dye metabolism by human intestinal microbiota.

    Science.gov (United States)

    Feng, Jinhui; Cerniglia, Carl E; Chen, Huizhong

    2012-01-01

    Approximately 0.7 million tons of azo dyes are synthesized each year. Azo dyes are composed of one or more R₁-N=N-R₂ linkages. Studies have shown that both mammalian and microbial azoreductases cleave the azo bonds of the dyes to form compounds that are potentially genotoxic. The human gastrointestinal tract harbors a diverse microbiota comprised of at least several thousand species. Both water-soluble and water-insoluble azo dyes can be reduced by intestinal bacteria. Some of the metabolites produced by intestinal microbiota have been shown to be carcinogenic to humans although the parent azo dyes may not be classified as being carcinogenic. Azoreductase activity is commonly found in intestinal bacteria. Three types of azoreductases have been characterized in bacteria. They are flavin dependent NADH preferred azoreductase, flavin dependent NADPH preferred azoreductase, and flavin free NADPH preferred azoreductase. This review highlights how azo dyes are metabolized by intestinal bacteria, mechanisms of azo reduction, and the potential contribution in the carcinogenesis/mutagenesis of the reduction of the azo dyes by intestinal microbiota.

  2. Indigo Dye Derived from Indigofera Tinctoria as Natural Food Colorant

    Science.gov (United States)

    Wahyuningsih, S.; Ramelan, A. H.; Wardani, D. K.; Aini, F. N.; Sari, P. L.; Tamtama, B. P. N.; Kristiawan, Y. R.

    2017-04-01

    Recently, the uses of dyes are increasingly widespread especially in foods and beverages as food colors to attract the consumers. The dye that currently attracts is indigo. Indigo is a group of carbonyl compounds, one of the oldest known dyes in terms of natural blue dye derived from the Indigofera tinctoria plant. The use of indigo as a natural food dye intended to reduce the use of synthetic dyes are carcinogenic impact. The method used in this study includes the analysis of indigo using UV-Vis spectrophotometry and FTIR analysis. Based on the UV-Vis Spectrophotometer analysis results with the various concentrations of 0.002 mg/mL; 0.004 mg/mL; 0.006 mg/mL and 0.008 mg/mL were obtained maximum absorption peak at wavelength of 550-700 nm. The indigo dyes in various concentrations produce a stable pH at an average pH 9, therefore it can make the colors not easily fade (strong staining). Based on infrared spectrophotometer measurement were obtained absorption spectrum at 3100-3500 cm-1 as primary N-H and secondary amine, 1600 cm-1 as aromatic C=C, 1000-1350 cm-1 as aromatic C-N, 690-900 cm-1 as aromatic C-H.

  3. Experimental Researches Regarding the Ecological Dyeing with Natural Extracts

    Directory of Open Access Journals (Sweden)

    Budeanu Ramona

    2014-12-01

    Full Text Available The concept of ‘environmental awareness’ has recently had a major impact on the textile industry and on the fashion world as well. In this context, the use of natural fibres and the development of natural dyeing processes gradually became important goals of the textile industry. Of all natural textile fibres, hemp is considered to be one of the strongest and most durable. A wide range of natural extracts have been used for natural textile coloration and dyeing. Dyes deriving from natural sources have emerged as an important alternative to synthetic dyes. Ecofriendly, nontoxic, sustainable and renewable natural dyes and pigments have been used for colouring the food substrate, leather, wood, natural fibres and fabrics from the dawn of human history. The purpose of the research is to obtain ecologically coloured fabrics for textiles by using a method of dyeing that relies on natural ingredients extracted from red beet, onion leaves and black tea. The experiments are conducted on three different types of hemp fabrics. This paper presents the results of the studies regarding the dyeing process of hemp fabrics with natural extracts, the colours of the dyed samples inspected with reflectance spectra and the CIE L*a*b* colour space measurements.

  4. Harvesting of microalgae cell using oxidized dye wastewater.

    Science.gov (United States)

    Seo, Yeong Hwan; Park, Doyoung; Oh, You-Kwan; Yoon, Sukhwan; Han, Jong-In

    2015-09-01

    In this study, oxidized dye wastewaters were tested for their potential to be used as a cheap coagulant for microalgae harvesting. Two dyes (methylene blue (MB) and methyl orange (MO)) were selected as model dyes, and the Fenton-like reaction under high temperature (90 °C, 1 min) employed as an oxidative treatment option. A maximum harvesting efficiency over 90% was obtained with both MB and MO at a dilution ratio of 5:1 (dye wastewater: cell culture), when the optimal oxidation condition was 20 mg/L of dye, 1 mM of FeCl3, and 0.5% of H2O2 concentration. This phenomenon could be explained by the possibility that amine groups are formed and exposed in oxidized dyes, which act as a kind of amine-based coagulant just like chitosan. This study clearly showed that dye wastewater, when properly oxidized, could serve as a potent coagulant for microalgae harvesting, potentially rendering the harvesting cost reduced to a substantial degree. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Microbial fuel cell with an azo-dye-feeding cathode

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Liang [Chinese Academy of Sciences, Guangzhou (China). Guangzhou Inst. of Geochemistry; Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou (China). Guangdon Key Lab. of Agricultural Environment Pollution Integrated Control; Graduate Univ. of Chinese Academy of Sciences, Beijing (China); Li, Fang-bai [Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou (China). Guangdon Key Lab. of Agricultural Environment Pollution Integrated Control; Feng, Chun-hua [South China Univ. of Technology, Guangzhou (China). School of Chemistry and Chemical Engineering; Li, Xiang-zhong [Hong Kong Polytechnic Univ., Hong Kong (China). Dept. of Civil and Structural Engineering

    2009-11-15

    Microbial fuel cells (MFCs) were constructed using azo dyes as the cathode oxidants to accept the electrons produced from the respiration of Klebsiella pneumoniae strain L17 in the anode. Experimental results showed that a methyl orange (MO)-feeding MFC produced a comparable performance against that of an air-based one at pH 3.0 and that azo dyes including MO, Orange I, and Orange II could be successfully degraded in such cathodes. The reaction rate constant ({kappa}) of azo dye reduction was positively correlated with the power output which was highly dependent on the catholyte pH and the dye molecular structure. When pH was varied from 3.0 to 9.0, the k value in relation to MO degradation decreased from 0.298 to 0.016 {mu}mol min{sup -1}, and the maximum power density decreased from 34.77 to 1.51 mW m{sup -2}. The performances of the MFC fed with different azo dyes can be ranked from good to poor as MO > Orange I > Orange II. Furthermore, the cyclic voltammograms of azo dyes disclosed that the pH and the dye structure determined their redox potentials. A higher redox potential corresponded to a higher reaction rate. (orig.)

  6. The Use of Vital Dyes during Vitreoretinal Surgery - Chromovitrectomy.

    Science.gov (United States)

    Farah, Michel Eid; Maia, Maurício; Penha, Fernando M; Rodrigues, Eduardo Büchele

    2016-01-01

    The aim of this article is to present the current data with regard to the application of vital dyes during vitreoretinal surgery, 'chromovitrectomy', as well as to overview the current literature regarding the properties of dyes, techniques of application, indications and complications in chromovitrectomy. It is well known that indocyanine green is toxic to the retina and consequently not the ideal dye for chromovitrectomy. Different vital dyes has been tested for chromovitrectomy including trypan blue, patent blue, triamcinolone acetonide, infracyanine green, sodium fluorescein and brilliant blue. Brilliant blue seems to be the ideal dye for internal limiting membrane due to its afinity, lower toxic profile and to reduce the appearance of apoptosis. Besides the dye itself, the injection technique is crucial to avoid additional toxicity, slow injection, far from the retina and protection of the macular hole are some tips. More recently the use of dyes has been applied to stain perfluorcarbon liquids that may enhance its visualization during vitrectomy. © 2016 S. Karger AG, Basel.

  7. Azo dye decolorization assisted by chemical and biogenic sulfide

    Energy Technology Data Exchange (ETDEWEB)

    Prato-Garcia, Dorian [Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230 (Mexico); Cervantes, Francisco J. [División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa de San José 2055, San Luis Potosí 78216 (Mexico); Buitrón, Germán, E-mail: gbuitronm@ii.unam.mx [Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230 (Mexico)

    2013-04-15

    Highlights: ► Azo dyes were reduced efficiently by chemical and biogenic sulfide. ► Biogenic sulfide was more efficient than chemical sulfide. ► There was no competition between dyes and sulfate for reducing equivalents. ► Aromatic amines barely affected the sulfate-reducing process. -- Abstract: The effectiveness of chemical and biogenic sulfide in decolorizing three sulfonated azo dyes and the robustness of a sulfate-reducing process for simultaneous decolorization and sulfate removal were evaluated. The results demonstrated that decolorization of azo dyes assisted by chemical sulfide and anthraquinone-2,6-disulfonate (AQDS) was effective. In the absence of AQDS, biogenic sulfide was more efficient than chemical sulfide for decolorizing the azo dyes. The performance of sulfate-reducing bacteria in attached-growth sequencing batch reactors suggested the absence of competition between the studied azo dyes and the sulfate-reducing process for the reducing equivalents. Additionally, the presence of chemical reduction by-products had an almost negligible effect on the sulfate removal rate, which was nearly constant (94%) after azo dye injection.

  8. Automated pressure scanning of tunable dye lasers

    Science.gov (United States)

    Gottscho, R. A.

    1985-04-01

    A method for the remote control of tunable laser frequency tuning is proposed in the framework of real-time monitoring of the chemistry and physics of plasma, combustion, and chemical vapor deposition reactions. The technique presented involves indirect frequency tuning and stabilization by direct control of the laser cavity pressure. The long-term drift in power, resulting from the grating and etalon misalignment is suggested to be correctable by using a second feedback circuit which would optimize laser power by finely tuning the etalon or grating. Experimental results obtained with a dye laser of Hansch type are included; a maximum variation in LIF signal of + or - 7 percent, which corresponds to a frequency drift of + or - 0.005/cm, over a 30-min interval was achieved. A block diagram of the feedback loop and the LIF apparatus are included.

  9. Synthesis, growth, structure and characterization of 1-Ethyl-2-(2-p-tolyl-vinyl)-pyridinium iodide (TASI) – An efficient material for third-order nonlinear optical applications

    Energy Technology Data Exchange (ETDEWEB)

    Nivetha, K. [Centre for Crystal Growth, School of Advanced Sciences, VIT University, Vellore 632 014 (India); Kalainathan, S., E-mail: kalainathan@yahoo.com [Centre for Crystal Growth, School of Advanced Sciences, VIT University, Vellore 632 014 (India); Yamada, M. [Research Center for Engineering Science, Graduate School of Engineering Science, Akita University, 1-1 Tegatagakuen-machi, Akita 010-8502 (Japan); Kondo, Y. [Department of Life Science, Graduate School of Engineering Science, Akita University, 1-1 Tegatagakuen-machi, Akita 010-8502 (Japan); Hamada, F. [Department of Applied Chemistry, Graduate School of Engineering Science, Akita University, 1-1 Tegatagakuen-machi, Akita 010-8502 (Japan)

    2017-02-15

    A new organic stilbazolium derivative, 1-Ethyl-2-(2-p-tolyl-vinyl)-pyridinium iodide (TASI), was grown from methanol:acetonitrile (1:3) mixed solvent by slow evaporation technique. Single crystal X-ray diffraction analysis revealed that TASI crystallizes in triclinic system with a centrosymmetric space group P-1. The molecular structure and the presence of expected functional groups of TASI were confirmed by {sup 1}H NMR and FT-IR spectroscopic studies. The HOMO and LUMO energies influence the charge transfer takes place within the molecule. The grown crystal was thermally stable up to 210 °C as determined by TG/DTA analysis. UV-Vis-NIR spectral study showed that the grown crystal was transparent in the wavelength range of 438–1100 nm. Mechanical behaviour and surface laser damage threshold were studied to find the suitability of the grown crystal for device fabrication. Studies of its third-order nonlinear optical properties using a Z-scan technique demonstrates that TASI crystal is capable of exhibiting reverse saturable absorption and self-focusing performance with the second-order molecular hyperpolarizability (γ) 4.983 × 10{sup −34} esu. The third-order nonlinear susceptibility of TASI was found to be 8.931 × 10{sup −6} esu, which is higher than a few other stilbazolium derivative crystals. - Highlights: • TASI is a new organic stilbazolium derivative and was grown by slow evaporation technique. • HOMO-LUMO analysis helps to explain charge transfer interaction within the molecule. • The grown crystal has 80% transmittance in the visible and near-IR spectral range. • Thermally, electrically and mechanically efficient for NLO applications. • Z-scan measurements reveal the aptness of the grown crystal for third order NLO applications.

  10. Environmental impact analysis of batik natural dyes using life cycle assessment

    Science.gov (United States)

    Rinawati, Dyah Ika; Sari, Diana Puspita; Purwanggono, Bambang; Hermawan, Andy Tri

    2017-11-01

    The use of natural dyes for batik dyeing is fewer than synthetic dyes because of its limitations in the application such complexity in manufacture and usage. For ease of use, natural dyes need to be processed into instant products. Extract of natural dyes are generally produced in liquid form that are less practical in long-term use. Dye powder obtained by drying the liquid extract using spray dryer. Production process of liquid natural dye is simpler and require less energy but need more energy for transporting. It is important to know which type of natural dyes should be produced based on their environmental impact. This research aim to compare environmental impact between liquid and powder natural dyes and also to find relative contribution of different stage in life cycle to total environmental impact. The appropriate method to analyze and compare the environmental impacts of powder and liquid natural dyes is Life Cycle Assessment (LCA). The "cradle to grave" approach used to assess environmental impact of powder and liquid natural dyes of Jalawe rind throughout production process of natural dyes, distribution and use of natural dyes for coloring batik. Results of this research show that powder natural dyes has lower environmental impacts than liquid natural dyes. It was found that distribution, mordanting and packaging of liquid dyes have big contribution to environmental impact.

  11. Immune responses to hair dyes containing toluene-2,5-diamine

    DEFF Research Database (Denmark)

    Schmidt, J D; Johansen, J D; Nielsen, M M

    2014-01-01

    BACKGROUND: Toluene-2,5-diamine (PTD) is the most frequently used dye in oxidative hair dyes on the Scandinavian market. However, little is known about immune responses to PTD-containing oxidative hair dyes. OBJECTIVES: To study immune responses induced by PTD-containing hair dyes in mice. METHODS...

  12. Study on pigment dyeing opportunities of polyester and cotton-mix fiber

    Science.gov (United States)

    Nabieva, I. A.; Shamukimova, M. B.; Artikboeva, R. M.

    2017-11-01

    The process of coloring the dyeing pigments in polyether and cotton fibers for different fabrics, which are inclined to dye, have been studied in this article. Based on the experiences on pigments dyeing, it was suggested to study the materials with the dyeing pigment substances with the purpose of improving the technology of color forming.

  13. PVA with nopal dye as holographic recording material

    Science.gov (United States)

    Toxqui-López, S.; Olivares-Pérez, A.; Fuentes-Tapia, I.; Pinto-Iguanero, B.

    2011-09-01

    Cactus nopal dye is introduced into a polyvinyl alcohol matrix achieving a like brown appearance thick film, such that they can be used as a recording medium. This dye material provides excellent property as photosensitizer, i.e., easy handling, low cost and can be used in real time holographic recording applications. The experimental results show the diffraction efficiencies obtained by recording grating patterns induced by a He-Cd laser (442nm). For the samples, a thick film of polyvinyl alcohol and dye from cactus nopal was deposited by the gravity technique on a glass substrate. This mixture dries to form a photosensitive emulsion.

  14. Biodegradation of azo dyes by genetically engineered azoreductase.

    Science.gov (United States)

    Wang, Jing; Yan, Bin; Zhou, Ji-Ti; Bao, Yong-Ming; Lu, Hong; Yuan, Xiao-Dong

    2005-01-01

    A azoreductase gene with 537 bp was obtained by PCR amplification from Rhodobacter sphaeroides AS1.1737. The enzyme, with a molecular weight of 18.7 kD, was efficiently expressed in Escherichia coli and its biodegradation characteristics for azo dyes were investigated. Furthermore, the reaction kinetics and mechanism of azo dyes catalyzed by the genetically engineered azoreductase were studied in detail. The presence of a hydrazo-intermediate was identified, which provided a convincing evidence for the assumption that azo dyes were degraded via an incomplete reduction stage.

  15. An experimental research about dye-doped distributed feedback laser

    Science.gov (United States)

    Zhou, Zhigang; Fan, Rongwei; Chen, Zhaodong; Xu, Xinrui; Chen, Deying

    2016-10-01

    Dye-doped distributed feedback (DFB) structure is an essential structure for DFB laser. This paper presents an operative method to design a kind of dye-doped distributed feedback laser based on dye-doped holographic polymer dispersed liquid crystal (HPDLC) matrix. The results show that we have processed DFB structure of 10μm period, with a relatively low period deviation of less than 1%. Furthermore, we gain output characteristics of DFB structure through experimental methods, which show good characteristics for wide tuning range, narrow linewidth laser output production.

  16. Experimental Researches Regarding the Ecological Dyeing with Natural Extracts

    OpenAIRE

    Budeanu Ramona; Curteza Antonela; Radu Cezar Doru

    2014-01-01

    The concept of ‘environmental awareness’ has recently had a major impact on the textile industry and on the fashion world as well. In this context, the use of natural fibres and the development of natural dyeing processes gradually became important goals of the textile industry. Of all natural textile fibres, hemp is considered to be one of the strongest and most durable. A wide range of natural extracts have been used for natural textile coloration and dyeing. Dyes deriving from natural sour...

  17. A comparative study of polymer-dye interaction

    Directory of Open Access Journals (Sweden)

    Nandini R.

    2009-08-01

    Full Text Available The interaction between an anionic dye Methyl Orange and two poly cations namely, Poly (N-vinyl-4-methylpyridiniumiodide, (PC1 & Poly (vinylbenzyltriphenylphosphoniumchloride, (PC2 has been investigated by spectrophotometric method. The polymers are observed to induce metachromasy in the dye as evidenced from the considerable blue shift in the absorption maximum of the dye. The interaction constant and thermodynamic parameters of interaction have been determined by absorbance measurements at the metachromatic band. The effect of additives such as ionic salts, alcohols, urea and polyelectrolytes on the reversal of metachromasy has been studied and used to determine the stability of the metachromatic complex and to understand the nature of binding.

  18. Review of Polymer, Dye-Sensitized, and Hybrid Solar Cells

    Directory of Open Access Journals (Sweden)

    S. N. F. Mohd-Nasir

    2014-01-01

    Full Text Available The combination of inorganic nanoparticles semiconductor, conjugated polymer, and dye-sensitized in a layer of solar cell is now recognized as potential application in developing flexible, large area, and low cost photovoltaic devices. Several conjugated low bandgap polymers, dyes, and underlayer materials based on the previous studies are quoted in this paper, which can provide guidelines in designing low cost photovoltaic solar cells. All of these materials are designed to help harvest more sunlight in a wider range of the solar spectrum besides enhancing the rate of charge transfer in a device structure. This review focuses on developing solid-state dye-synthesized, polymer, and hybrid solar cells.

  19. A switchable digital microfluidic droplet dye-laser.

    Science.gov (United States)

    Kuehne, Alexander J C; Gather, Malte C; Eydelnant, Irwin A; Yun, Seok-Hyun; Weitz, David A; Wheeler, Aaron R

    2011-11-07

    Digital microfluidic devices allow the manipulation of droplets between two parallel electrodes. These electrodes can act as mirrors generating a micro-cavity, which can be exploited for a droplet dye-laser. Three representative laser-dyes with emission wavelengths spanning the whole visible spectrum are chosen to show the applicability of this concept. Sub-microlitre droplets of laser-dye solution are moved in and out of a lasing site on-chip to down-convert the UV-excitation light into blue, green and red laser-pulses. This journal is © The Royal Society of Chemistry 2011

  20. Visible to near infra red absorption in natural dye (Mondo Grass Berry) for Dye Sensitized Solar Cell

    Science.gov (United States)

    Pitigala, Duleepa; Desilva, L. A. A.; Perera, A. G. U.

    2012-03-01

    The development of dye sensitized solar cells (DSSC) is an exciting field in the low cost renewable energy production. Two major draw backs in the DSSCs are the narrow spectral response and the short term stability. Research on development of artificial dyes for broadening the response is important in finding a solution. Work presented here shows a broad spectral response with a natural dye extracted from a Mondo Grass berry (Ophiopogonjaponicus).The dye is extracted by crushing the berries and filtering to remove the pulp. A DSSC sensitized with Mondo Grass dye, and with TiO2 film screen printed on a Florien doped Tin Oxide (FTO) glass and baked for 30 minutes at 450 C as the working electrode and Iodine/triiodide red-ox electrolyte as the hole collector was tested for its performance. An open circuit photovoltage of 495 mV and a short circuit photocurrent of 0.6 mA/cm2were observed under a simulated lamp equivalent to 1 sun illumination. The broad spectral response from 400 nm to 750 nm was also observed for the Mondo Grass dye compared to other natural dyes consists of anthocyanins or tannins.

  1. Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells.

    Science.gov (United States)

    Selopal, Gurpreet Singh; Wu, Hui-Ping; Lu, Jianfeng; Chang, Yu-Cheng; Wang, Mingkui; Vomiero, Alberto; Concina, Isabella; Diau, Eric Wei-Guang

    2016-01-07

    We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-π-A concept to extending the light absorption region by strong conjugation group of π-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film. Transient photocurrent and photovoltage decay measurements (TCD/TVD) were applied to systematically study the charge transport and recombination kinetics in these devices, showing the electron life time (τR) of B18 dye in ZnO and TiO2 based DSSCs is higher than CPTD-R and BTD-R based DSSCs, which is consistent with the photovoltaic performances. The conversion efficiency in ZnO based DSSCs can be further boosted by 35%, when a compact ZnO blocking layer (BL) is applied to inhibit electron back reaction.

  2. Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells

    Science.gov (United States)

    Selopal, Gurpreet Singh; Wu, Hui-Ping; Lu, Jianfeng; Chang, Yu-Cheng; Wang, Mingkui; Vomiero, Alberto; Concina, Isabella; Diau, Eric Wei-Guang

    2016-01-01

    We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-π-A concept to extending the light absorption region by strong conjugation group of π-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film. Transient photocurrent and photovoltage decay measurements (TCD/TVD) were applied to systematically study the charge transport and recombination kinetics in these devices, showing the electron life time (τR) of B18 dye in ZnO and TiO2 based DSSCs is higher than CPTD-R and BTD-R based DSSCs, which is consistent with the photovoltaic performances. The conversion efficiency in ZnO based DSSCs can be further boosted by 35%, when a compact ZnO blocking layer (BL) is applied to inhibit electron back reaction. PMID:26738698

  3. Role of the triiodide/iodide redox couple in dye regeneration in p-type dye-sensitized solar cells.

    Science.gov (United States)

    Gibson, Elizabeth A; Le Pleux, Loïc; Fortage, Jérôme; Pellegrin, Yann; Blart, Errol; Odobel, Fabrice; Hagfeldt, Anders; Boschloo, Gerrit

    2012-04-17

    A series of perylene dyes with different optical and electronic properties have been used as photosensitizers in NiO-based p-type dye-sensitized solar cells. A key target is to develop dyes that absorb light in the red to near-infrared region of the solar spectrum in order to match photoanodes optically in tandem devices; however, the photocurrent produced was found to decrease dramatically as the absorption maxima of the dye used was varied from 517 to 565 nm and varied strongly with the electrolyte solvent (acetonitrile, propionitrile, or propylene carbonate). To determine the limitations of the energy properties of the dye molecules and to provide guidelines for future sensitizer design, we have determined the redox potentials of the diiodide radical intermediate involved in the charge-transfer reactions in different solvents using photomodulated voltammetry. E°(I(3)(-)/I(2)(•-)) (V vs Fe(Cp)(2)(+/0)) = -0.64 for propylene carbonate, -0.82 for acetonitrile, and -0.87 for propionitrile. Inefficient regeneration of the sensitizer appears to be the efficiency-limiting step in the device, and the values presented here will be used to design more efficient dyes, with more cathodic reduction potentials, for photocathodes in tandem dye-sensitized solar cells. © 2012 American Chemical Society

  4. A Study on the Efficiency Improvement of Dye-Sensitized Solar Cell (DSSC) by Repeated Dye Coating.

    Science.gov (United States)

    Seo, Young Ho; Choi, Eun Chang; Hong, Byungyou

    2015-10-01

    Dye-sensitized solar cell (DSSC) is being extensively investigated as the next generation energy source. Despite of the attractive features like simple fabrication process and its economic efficiency, there are some problems such as low efficiency, long fabrication time and low long-term stability. Conventionally, the dye adsorption on TiO2 photo-electrode film needs long time in the solvent with low concentration of dye to get the high efficiency. In this work, the dye coating process was considerably shortened, albeit plenty of dye was used comparing with the conventional way. Our needs were met for the best result in our working environment and the relevant conditions to our work were obtained, which were the coating temperature of 70 °C, the dye concentration of 10 mM and the coating time of 3 min. And this coating process was successively repeated several times to maximize the dye adsorption and to improve the cell efficiency. Therefore, the efficiency increased by 13% in the proper condition.

  5. Electrochemical removal of synthetic textile dyes from aqueous solutions using Ti/Pt anode: role of dye structure.

    Science.gov (United States)

    Araújo, Cynthia K C; Oliveira, Gustavo R; Fernandes, Nedja S; Zanta, Carmem L P S; Castro, Suely Souza Leal; da Silva, Djalma R; Martínez-Huitle, Carlos A

    2014-01-01

    In this work, the efficiency of electrochemical oxidation (EO) was investigated for removing a dye mixture containing Novacron Yellow (NY) and Remazol Red (RR) in aqueous solutions using platinum supported on titanium (Ti/Pt) as anode. Different current densities (20, 40 and 60 mA cm(-2)) and temperatures (25, 40 and 60 °C) were studied during electrochemical treatment. After that, the EO of each of these dyes was separately investigated. The EO of each of these dyes was performed, varying only the current density and keeping the same temperature (25 °C). The elimination of colour was monitored by UV-visible spectroscopy, and the degradation of organic compounds was analysed by means of chemical oxygen demand (COD). Data obtained from the analysis of the dye mixture showed that the EO process was effective in colour removal, in which more than 90% was removed. In the case of COD removal, the application of a current density greater than 40 mA cm(-2) favoured the oxygen evolution reaction, and no complete oxidation was achieved. Regarding the analysis of individual anodic oxidation dyes, it was appreciated that the data for the NY were very close to the results obtained for the oxidation of the dye mixture while the RR dye achieved higher colour removal but lower COD elimination. These results suggest that the oxidation efficiency is dependent on the nature of the organic molecule, and it was confirmed by the intermediates identified.

  6. Formation of shaped barium sulfate-dye hybrids: waste dye utilization for eco-friendly treatment of wastewater.

    Science.gov (United States)

    Gao, Hong-Wen; Lin, Jing; Li, Wei-Ying; Hu, Zhang-Jun; Zhang, Ya-Lei

    2010-01-01

    Owing to the present complexity and difficulty of concentrated dye wastewater treatment, this work aimed to synthesize a reproducible waste-sorbing material for the treatment of wastewater by forming the dye-conjugating complex hybrid. The inorganic/organic hybridization was applied to prepare the objective material by immobilizing waster dye-Mordant blue 9 (MB) with barium sulfate (BaSO4). The composition and pattern of the formed material were determined by spectrometry and characterized by SEM and XRD, and their formation process was clarified. The adsorption of cationic dye-basic blue BO (BB) and copper ion was investigated. The hybrid of MB alone into growing BaSO4 formed the pineapple-like particles while that of the MB/BB-conjugating complex was the rhombus material. The adsorption of BB on the MB-BaSO4 hybrid was probably attributed to ion-pair equilibrium and that of Cu2+ may result from the complexation. The treatment of dye and heavy metal wastewaters indicated that the MB hybrid material removed 99.8% BB and 97% Cu2+ and the dye-conjugating hybrid with growing BaSO4 100% MB, 99.5% BB, and 44% Cu2+. The waste MB-BaSO4 hybrid material is efficient to treat cationic dye and Cu2+ wastewater. The dye-conjugating hybridization method is the first to be advanced for in situ wastewater treatment, and it showed a combined effect for the removal of both organic dyes and heavy metals.

  7. Diphenyl (4′-(Aryldiazenylbiphenyl-4-ylamino(pyridin-3-ylmethylphosphonates as Azo Disperse Dyes for Dyeing Polyester Fabrics

    Directory of Open Access Journals (Sweden)

    Mohamed F. Abdel-Megeed

    2013-01-01

    Full Text Available Diphenyl (4′-aminobiphenyl-4-ylamino(pyridin-3-ylmethylphosphonate (1 was synthesized in 88% yield from reaction of pyridine-3-carboxaldehyde with benzidine and triphenylphosphite in the presence of titanium tetrachloride as a catalyst. Diazotization of 1 gave the corresponding diazonium salt 2 which was coupled with several hydroxyl or amino compounds to give the corresponding azo dyes 3–8 in 82–88% yields after crystallization. The dyes produced were applied to polyesters as disperse dyes and their fastness properties were elevated.

  8. Synthesis of Some Novel 2-Amino-5-arylazothiazole Disperse Dyes for Dyeing Polyester Fabrics and Their Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Hatem E. Gaffer

    2016-01-01

    Full Text Available The present work describes the synthesis of a series of four novel biologically active 2-amino-5-arylazothiazole disperse dyes containing the sulfa drug nucleus. The structures of the synthesized thiazole derivatives are confirmed using UV-spectrophotometry, infrared and nuclear magnetic resonance techniques and elemental analysis. The synthesized dyes are applied to polyester fabrics as disperse dyes and their fastness properties to washing, perspiration, rubbing, sublimation, and light are evaluated. The synthesized compounds exhibit promising biological efficiency against selected Gram-positive and Gram-negative pathogenic bacteria as well as fungi.

  9. Synthesis, dyeing performance on polyester fiber and antimicrobial studies of some novel pyrazolotriazine and pyrazolyl pyrazolone azo dyes

    OpenAIRE

    Rizk, Hala F.; Ibrahim, Seham A.; El-Borai, Mohammed A.

    2014-01-01

    5-Amino-4-heterylazo-3-phenyl-1H-pyrazoles (2a–d) were diazotized and coupled with malononitrile to give pyrazoloazo malononitrile which by heating in glacial acetic acid gave novel pyrazolo[5,1-c][1,2,4]triazine dyes (3a–d). Also, some diazopyrazolyl pyrazolone dyes (4a–h) were synthesized by diazotization of 2a–d and coupled with some pyrazolone derivatives. The structure of the synthesized dyes was determined by elemental analysis and spectral data. All the synthesized compounds were appli...

  10. The effect of Cu doping into Oriza sativa L. indica dye as photosensitizer for dye sensitized solar cell (DSSC)

    Science.gov (United States)

    Fadli, U. M.; Prasada, A. B.; Cari; Supriyanto, A.

    2016-11-01

    The aims of the research to are know the effect of Cu doping into natural dye in increasing the efficiency of DSCC, to determine of the optical and electrical characteristic of natural dye Cu doping. Sandwich structures formed in the sample consisted of working electrode pair Titanium Oxide (TiO2) and the counter electrode Platina (Pt). Absorbance test is measure by using UV-Visible spectrophotometer Lambda 25, conductivity test by using a two- point probe El Kahfi/I-V Meter, and characterization of current and voltage (I-V) by using a Keithley 2602A. The Cu doping into dye was increasing the efficiency of 71%.

  11. The removal of reactive dyes using high-ash char

    Directory of Open Access Journals (Sweden)

    Moreira R.F.P.M.

    2001-01-01

    Full Text Available The thermodynamics and kinetics of adsorption of reactive dyes on high-ash char was studied. Equilibrium data were obtained using the static method with controlled agitation at temperatures in the range of 30 to 60ºC. The Langmuir isotherm model was used to describe the equilibrium of adsorption, and the equilibrium parameters, R L, in the range of 0 to 1 indicate favorable adsorption. The amount of dye adsorbed increased as temperature increased from 30 to 40ºC, but above 40ºC the increase in temperature resulted in a decrease in the amount of dye adsorbed. The kinetic data presented are for controlled agitation at 50 rpm and constant temperature with dye concentrations in the range of 10 ppm to50 ppm. The film mass transfer coefficient, Kf, and the effective diffusivity inside the particle, De, were fitted to the experimental data. The results indicate that internal diffusion governs the adsorption rate.

  12. A spectroscopic study of interaction of cationic dyes with heparin

    Directory of Open Access Journals (Sweden)

    R. Nandini

    2010-01-01

    Full Text Available The interaction of two cationic dyes namely, acridine orange and pinacyanol chloride with an anionic polyelectrolyte, heparin, has been investigated by spectrophotometric method.The polymer induced metachromasy in the dyes resulting in the shift of the absorption maxima of the dyes towards shorter wavelengths. The stability of the complexes formed between acridine orange and heparin was found to be lesser than that formed between pinacyanol chloride and heparin. This fact was further confirmed by reversal studies using alcohols, urea and surfactants. The interaction of acridine orange with heparin has also been investigated fluorimetrically.The interaction parameters revealed that binding between acridine orange and heparin arises due to electrostatic interaction while that between pinacyanol chloride and heparin is found to involve both electrostatic and hydrophobic forces. The effect of the structure of the dye in inducing metachromasy has also been discussed.

  13. Novel squarylium dyes for detection of amyloid fibrils in vitro

    Directory of Open Access Journals (Sweden)

    K. O. Vus

    2015-04-01

    Full Text Available A series of novel symmetrical and asymmetrical squarylium dyes with the different substituents in the donor moieties have been tested for their ability to detect and characterize insulin and lysozyme amyloid fibrils prepared in acidic buffer at elevated temperature. The dye-protein binding parameters were estimated in terms of the one-site Langmuir adsorption model using the data of direct and reverse fluorimetric titrations. By comparing the dye quantum yields, binding affinities, and extents of the fluorescence enhancement in the protein-bound state, G6 and G7 were selected as the most prospective amyloid tracers. Furthermore, these probes provided evidence for the lower polarity of the lysozyme fibrillar grooves compared to insulin aggregates. The novel dyes G6 and G7 were recommended for amyloid fibril detection and characterization in the near-infrared region.

  14. Synthesis of Some Monoazo Disperse Dyes Derived from Aminothienochromene

    Directory of Open Access Journals (Sweden)

    Morsy Ahmed El-Apasery

    2013-07-01

    Full Text Available A series of azo disperse dyes based on aminothienochromene were synthesized. The fastness properties of the dyed samples were measured. Most of the dyed fabrics tested displayed excellent washing and perspiration fastness and moderate light fastness.

  15. Decolorization of synthetic dyes and textile effluents by basidiomycetous fungi

    Digital Repository Service at National Institute of Oceanography (India)

    Diwaniyan, S.; Kharb, D.; Raghukumar, C.; Kuhad, R.C.

    tested in liquid cultures. A statistically significant positive correlation between laccase production and decolorization of dyes and effluents was obtained as compared to other ligninolytic enzymes (lignin peroxidase and manganese peroxidase) production...

  16. Dye-sensitized solar cells based on purple corn sensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Phinjaturus, Kawin [Materials Science and Nanotechnology Program, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Maiaugree, Wasan [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Suriharn, Bhalang [Department of Plant Science and Agricultural Resources, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002 (Thailand); Pimanpaeng, Samuk; Amornkitbamrung, Vittaya [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Integrated Nanotechnology Research Center (INRC), Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Swatsitang, Ekaphan, E-mail: ekaphan@kku.ac.th [Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Integrated Nanotechnology Research Center (INRC), Department of Physics, Faculty of Science, Khon Kaen University, Khon Kaen 40002 (Thailand); Nanotec-KKU Center of Excellence on Advanced Nanomaterials for Energy Production and Storage, Khon Kaen 40002 (Thailand)

    2016-09-01

    Graphical abstract: - Highlights: • Extract from husk, cob and silk of purple corn was used as a photosensitizer in DSSC. • Effect of solvents i.e. acetone, ethanol and DI water on DSSC efficiency was studied. • The highest efficiency of 1.06% was obtained in DSSC based on acetone extraction. - Abstract: Natural dye extracted from husk, cob and silk of purple corn, were used for the first time as photosensitizers in dye sensitized solar cells (DSSCs). The dye sensitized solar cells fabrication process has been optimized in terms of solvent extraction. The resulting maximal efficiency of 1.06% was obtained from purple corn husk extracted by acetone. The ultraviolet–visible (UV–vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and incident photon-to-current efficiency (IPCE) were employed to characterize the natural dye and the DSSCs.

  17. Bioflocculation of Basic Dye onto Isolated Microbial Biopolymers

    Directory of Open Access Journals (Sweden)

    M. Elkady

    2017-10-01

    Full Text Available Three purified biopolymers isolated from Bacillus velezensis (40B, Bacillus mojavensis (32A and Pseudomonas (38A strains were evaluated for dye decolourization as bioflocculants. The decolourization capacity of the three polymers was inspected using C.I 28 basic yellow dye as hazardous pollutant. The chemical compositions of these purified biopolymers were considered by HPLC and FTIR spectrum. The decolourization efficiency of the three purified biopolymers was determined using both real dye polluted wastewater (discharged from AKSA EGYPT acrylic fibres industry and simulated synthetic wastewater. The maximum decolourization efficiencies of the purified biopolymers of the three studied strains (40B, (32A and (38A were 91, 89 and 88 %, respectively. The equilibrium of dye sorption process onto biopolymers was described using Langmuir isotherm equation. However, its kinetics follows the pseudo second order model. The thermodynamic examination investigated the exothermic and spontaneous nature of the decolourization process using the purified biopolymers.

  18. Spectophotometric Study of Interaction between Sodium Carrageenate and Cationic Dyes

    Directory of Open Access Journals (Sweden)

    R. Nandini

    2011-01-01

    Full Text Available The interaction of two cationic dyes, namely, methylene (MB and acridine orange (AO with an anionic polyelectrolyte, namely, sodium carrageenate (NaCar has been investigated by spectrophotometric method and spectrofluorimetric method. The polymer induced metachromasy in the dyes resulting in the shift of the absorption maxima of the dyes towards shorter wavelengths.The stability of the complexes formed between acridine orange and sodium carrageenate was found to be lesser than that formed between methylene blue and sodium carrageenate. This fact was further confirmed by reversal studies using alcohols, urea, surfactants and electrolytes. The interaction parameters revealed that binding between acridine orange and sodium carrageenate was mainly due to electrostatic interaction while that between methylene blue and carrageenate is found to involve both electrostatic and hydrophobic forces. The effect of the structure of the dye and its relation to metachromasy has been discussed.

  19. Relaxation dynamics in the excited states of a ketocyanine dye ...

    Indian Academy of Sciences (India)

    propdienylaniline)-cyclopentanone (MPAC), a ketocyanine dye, have been investigated using steady-state absorption and emission as well as femtosecond time-resolved absorption spectroscopic techniques. Following photoexcitation using 400 ...

  20. Electron injection at dye-sensitized semiconductor electrodes.

    Science.gov (United States)

    Watson, David F; Meyer, Gerald J

    2005-01-01

    Electron injection at dye-sensitized semiconductors is reviewed. Particular emphasis is placed on theoretical and photoelectrochemical studies of dye-sensitized planar and single-crystal electrodes. The accepted mechanism of electron injection, which was derived from these classical studies, is introduced. Selected photoelectrochemical studies of dye-sensitized nanocrystalline semiconductors are reviewed; emphasis is given to factors that influence the efficiencies of electron injection and charge recombination. The development of quasi-solid-state nanocrystalline dye-sensitized solar cells is also discussed. Recent time-resolved spectroscopic studies of electron injection and charge recombination are reviewed. These studies have led to a better understanding of electron injection mechanisms, and have revealed the limitations of the classical models.