Sample records for crystal violet dye

  1. On the interaction of triarylmethane dye crystal violet with LAPONITE® clay: using mineral nanoparticles to control the dye photophysics.

    PubMed

    Ley, C; Brendlé, J; Walter, A; Jacques, P; Ibrahim, A; Allonas, X

    2015-06-24

    The combination of an organic dye with clays leads to very interesting hybrid materials with original properties. It is found that LAPONITE® nanoparticles have an impact on the photophysical properties of the crystal violet dye inducing a kinetic stabilization of its excited emissive state, turning this nonemissive dye into a fluorescent compound. PMID:26028222

  2. An LED Approach for Measuring the Photocatalytic Breakdown of Crystal Violet Dye

    NASA Technical Reports Server (NTRS)

    Ryan, Robert E.; Underwood, Lauren W.; ONeal, Duane; Pagnutti, Mary; Davis, Bruce A.

    2009-01-01

    A simple technique to assess the reactivity of photocatalytic coatings sprayed onto transmissive glass surfaces was developed. This new method uses ultraviolet (UV) gallium nitride (GaN) light-emitting diodes (LEDs) to drive a photocatalytic reaction (the photocatalytic breakdown of a UV-resistant dye applied to a surface coated with the semiconductor titanium dioxide); and then a combination of a stabilized white light LED and a spectrometer to track the dye degradation as a function of time. Simple, standardized evaluation techniques that assess photocatalytic materials over a variety of environmental conditions, including illumination level, are not generally available and are greatly needed prior to in situ application of photocatalytic technologies. To date, much research pertaining to this aspect of photocatalysis has been limited and has focused primarily on laboratory experiments using mercury lamps. Mercury lamp illumination levels are difficult to control over large ranges and are temporally modulated by line power, limiting their use in helping to understand and predict how photocatalytic materials will behave in natural environmental settings and conditions. The methodology described here, using steady-state LEDs and time series spectroradiometric techniques, is a novel approach to explore the effect of UV light on the photocatalytic degradation of a UV resistant dye (crystal violet). GaN UV LED arrays, centered around 365 nm with an adjustable DC power supply, are used to create a small, spatially uniform light field where the steady state light level can be varied over three to four orders of magnitude. For this study, a set of glass microscope slides was custom coated with a thinly sprayed layer of photocatalytic titanium dioxide. Crystal violet was then applied to these titanium-dioxide coated slides and to uncoated control slides. The slides were then illuminated at various light levels from the dye side of the slide by the UV LED array. To monitor dye degradation on the slides over time, a temperature-stabilized white light LED was used to illuminate the opposite side of the slides. As the dye degraded, the amount of light from the white light LED transmitted through the slide was monitored with a spectrometer and subsequently analyzed to determine and compare the rate of dye degradation for photocatalytically coated versus uncoated slide surfaces. The long-term stability of the spectrometer/white light LED combination, which required only a single reference spectra to be taken for a time series sequence of several hours, enabled accurate measurements of transmitted light over time. Time series transmission curves were generated and results demonstrated that over time the transmission increased much more rapidly on the coated slides than on the control slides. This experimental configuration and methodology for photocatalytic activity measurement minimizes many external variable effects and allows low light level studies to be performed. This study also compares the advantages of this novel LED light source design to traditional mercury lamp systems and non-LED lamp approaches that have conventionally been used. The methodology and experimental design research summarized in this abstract is partly funded by the Department of Homeland Security, Science and Technology Directorate, and by the NASA Stennis Space Center Innovative Partnerships Program.

  3. Study of Surface Enhanced Raman Scattering of Alizarin and Crystal Violet Dyes

    NASA Astrophysics Data System (ADS)

    Gopal, Ram; Swarnkar, Raj Kumar

    2010-06-01

    Surface enhanced Raman scattering (SERS) plays a vital role in analytical chemistry to characterize ultra trace quantity of organic compounds and biological samples. Two mechanisms have been considered to explain the SERS effect. The main contribution arises from a huge enhancement of the local electromagnetic field close to surface roughness of the metal structures, due to the excitation of a localized surface plasmon, while a further enhancement can be observed for molecules adsorbed onto specific sites when resonant charge transfer occurs. SERS signals have been observed from adsorbates on many metallic surfaces like Ag, Au, Ni, Cu etc. Additionally, metal oxide nanoparticles also show SERS signals It has now been established that SERS of analyte material is highly dependent on the type of substrate involved. Many types of nanostructures like nanofilms, nanorods, nanospheres etc. show highly efficient SERS signals. In particular, there are two routes available for the synthesis of these nanomaterials: the chemical route and the physical route. Chemical route involves many types of reducing agents and capping agents which can interfere in origin and measurement of these signals. The physical route avoids these anomalies and therefore it is suitable for the study of SERS phenomenon. Pulsed laser ablation in liquid medium is an excellent top down technique to produce colloidal solution of nanoparticles with desired shape and size having surface free from chemical contamination, which is essential requirement for surface application of nanoparticles. The present work deals with the study of SERS of Crystal violet dye and Alizarin group dye on Cu@ Cu_2O and Ag colloidal nanoparticles synthesized by pulsed laser ablation. M. Fleishchmann, P. J. Hendra, and A. J. McQuillian Chem. Phys. Lett., 26, 163, 1974. U. Wenning, B. Pettinger, and H. Wetzel Chem. Phys. Lett., 70, 49, 1980. S. C. Singh, R. K. Swarnkar, P. Ankit, M. C. Chattopadhyaya, and R. Gopal AIP Conf. Proc., 1075, 67, 2008. S. C. Singh, R. K. Swarnkar, and R. Gopal J. Nanosci.. Nanotech., 9, 5367, 2009. R. K. Swarnkar, S. C. Singh, and R. Gopal AIP Conf. Proc., 1147, 205, 2009.

  4. Equilibrium, kinetics and mechanism modeling and simulation of basic and acid dyes sorption onto jute fiber carbon: Eosin yellow, malachite green and crystal violet single component systems

    Microsoft Academic Search

    K. Porkodi; K. Vasanth Kumar

    2007-01-01

    Batch experiments were carried out for the sorption of eosin yellow, malachite green and crystal violet onto jute fiber carbon (JFC). The operating variables studied are the initial dye concentration, initial solution pH, adsorbent dosage and contact time. Experimental equilibrium data were fitted to Freundlich, Langmuir and Redlich–Peterson isotherm by non-linear regression method. Langmuir isotherm was found to be the

  5. Simultaneous removal of binary mixture of Brilliant Green and Crystal Violet using derivative spectrophotometric determination, multivariate optimization and adsorption characterization of dyes on surfactant modified nano-?-alumina.

    PubMed

    Zolgharnein, Javad; Bagtash, Maryam; Shariatmanesh, Tahere

    2015-02-25

    The present study deals with the simultaneous removal of Brilliant Green (BG) and Crystal Violet (CV) by surfactant-modified alumina. The utilization of alumina nanoparticles with an anionic surfactant (sodium dodecyl sulfate (SDS)) as a novel and efficient adsorbent is successfully carried out to remove two cationic dyes from aqueous solutions in binary batch systems. A first-order derivative spectrophotometric method is developed for the simultaneous determination of BG and CV in binary solutions. The linear concentration range and limits of detection for the simultaneous determination of BG and CV were found to be: 1-20, 1-15 mg/L, 0.3 and 0.5 mg/L, respectively. The influence of various parameters, such as contact time, initial concentration of dyes and sorbent mass on the dye adsorption is investigated. A response surface methodology achieved through performing the Box-Behnken design is utilized to optimize the removal of dyes by surfactant-modified nanoparticle alumina through a batch adsorption process. The proposed quadratic model resulting from the Box-Behnken design approach fitted very well with the experimental data. The optimal conditions for dye removal were contact time t=50 min, sorbent dose=0.036 g, CBG (Initial BG concentration)=215 mg/L and CCV (Initial CV concentration)=170 mg/L. Furthermore, FT-IR analysis, the isotherms and kinetics of adsorption were also explored. PMID:25286114

  6. Crystal violet: Study of the photo-fading of an early synthetic dye in aqueous solution and on paper with HPLC-PDA, LC-MS and FORS

    NASA Astrophysics Data System (ADS)

    Confortin, Daria; Neevel, Han; Brustolon, Marina; Franco, Lorenzo; Kettelarij, Albert J.; Williams, Renè M.; van Bommel, Maarten R.

    2010-06-01

    The photo-fading of crystal violet (CV), one of the earliest synthetic dyes and an ink component, is examined both in solution and on paper. Aqueous solutions of CV were exposed to UV light (365nm) and samples were taken at constant time intervals and analysed with a High Performance Liquid Chromatography-Photo Diode Array (HPLC-PDA) and Liquid Chromatography-Mass Spectroscopy (LC-MS). Demethylation products were positively identified. Also, deamination probably occurred. The oxidation at the central carbon likely generates Michler's ketone (MK) or its derivatives, but still needs confirmation. To study CV on paper, Whatman paper was immersed in CV and exposed to UV light. Before and after different irradiation periods, reflectance spectra were recorded with Fibre Optic Reflectance Spectrophotometry (FORS). A decrease in CV concentration and a change in aggregation type for CV molecules upon irradiation was observed. Colorimetric L*a*b* values before and during irradiation were also measured. Also, CV was extracted from paper before and after different irradiation periods and analysed with HPLC-PDA. Photo-fading of CV on paper produced the same products as in solution, at least within the first 100 hours of irradiation. Finally, a photo-fading of CV in the presence of MK on Whatman paper was performed. It was demonstrated that MK both accelerates CV degradation and is consumed during the reaction. The degradation pathway identified in this work is suitable for explaining the photo/fading of other dyes belonging to the triarylmethane group.

  7. Physicochemical characteristics of patent blue violet dye.

    PubMed

    Newton, D W; Breen, P J; Brown, D E; Mackie, J F; Kluza, R B

    1981-02-01

    Physicochemical data for patent blue violet dye (I) are reported. The pKa for protonation of the first diethylanilino group was 2.78 +/- 0.03. The absorptivity values calculated for a 1% (w/v) solution of previously dried I at pH 7.4 were 1650, 170, and 250 at 638, 412, and 309 nm, respectively. A table of wavelength maxima and observed solution color as a function of pH and Ho and five spectra of I at certain pH and Ho values are included. The solution chemistry of I is explained, and a scheme showing its two protonated carbonium ions and its triphenylcarbinol derivative is presented. The distribution coefficients of I in n-octanol or chloroform and pH 7.4 phosphate buffer systems were 0.013 and 0.12, respectively. The approximate solubilities at 25 degrees of I in six organic solvents and the solubility analysis of I in distilled water are reported. Results of the latter analysis suggest that I forms a lyotropic mesophase in high aqueous concentrations. Compound I is poorly lipid soluble. Samples of 1.000% I in 0.9% NaCl, formulated with and without 1% (v/v) benzyl alcohol and autoclaving, varied not more than 5% from the initial I content during storage in the dark and under constant fluorescent light at 25 +/- 5 degrees for 20 months. Data from the TLC of I in several eluents indicated a high degree of purity of the dye. The half-lives for the loss of color in 5 X 10(-4)% I solutions in potassium hydroxide solutions of pH 13.7, 12.7, 11.3, and 10.0 were 1.2 hr, 17.0 hr, 9.5 days, and 180 days, respectively. The fraction of I bound to 4% (w/v) human serum albumin at 37 degrees and pH 7.4 ranged from 0.05 to 0.83, corresponding to unbound I in the postdialysis concentration range of 1.7 X 10(-4) to 2.0% (w/v). A Scatchard plot of the albumin binding data of I revealed one high-affinity binding site, K = 6235 M-1, and five low-affinity sites, with average affinity constants of 33 M-1. The data support the fact that the spectrophotometric determination of I at 639 +/- 2 nm appears to comprise a stability-indicating assay. PMID:7205212

  8. Biodegradation of crystal violet by the white rot fungus Phanerochaete chrysosporium.

    PubMed Central

    Bumpus, J A; Brock, B J

    1988-01-01

    Biodegradation of crystal violet (N,N,N',N',N'',N''-hexamethylpararosaniline) in ligninolytic (nitrogen-limited) cultures of the white rot fungus Phanerochaete chrysosporium was demonstrated by the disappearance of crystal violet and by the identification of three metabolites (N,N,N',N',N''-pentamethylpararosaniline, N,N,N',N''-tetramethylpararosaniline, and N,N',N''-trimethylpararosaniline) formed by sequential N-demethylation of the parent compound. Metabolite formation also occurred when crystal violet was incubated with the extracellular fluid obtained from ligninolytic cultures of this fungus, provided that an H2O2-generating system was supplied. This, as well as the fact that a purified ligninase catalyzed N-demethylation of crystal violet, demonstrated that biodegradation of crystal violet by this fungus is dependent, at least in part, upon its lignin-degrading system. In addition to crystal violet, six other triphenylmethane dyes (pararosaniline, cresol red, bromphenol blue, ethyl violet, malachite green, and brilliant green) were shown to be degraded by the lignin-degrading system of this fungus. An unexpected result was the finding that substantial degradation of crystal violet also occurred in nonligninolytic (nitrogen-sufficient) cultures of P. chrysosporium, suggesting that in addition to the lignin-degrading system, another mechanism exists in this fungus which is also able to degrade crystal violet. PMID:3389809

  9. Biodegradation of crystal violet by the white rot fungus phanerochaete chrysosporium

    SciTech Connect

    Bumpus, J.A.; Brock, B.J.

    1988-01-01

    Biodegradation of crystal violet (N,N,N',N',N',N''- hexamethylpararosaniline) in ligninolytic (nitrogen-limited) cultures of the white rot fungus Phanerochaete chrysosporium was demonstrated by the disappearance of crystal violet and by the identification of three metabolites (N,N,N',N',N'' -pentamethylpararosaniline, N,N,N',N'' -tetramethylpararosaniline, and N,N',N'' -trimethylpararosaniline) formed by sequential N-demethylation of the parent compound. Metabolite formation also occurred when crystal violet was incubated with the extracellular fluid obtained from ligninolytic cultures of this fungus, provided that an H2O2-generating system was supplied. This, as well as the fact that a purified ligninase catalyzed N-demethylation of crystal violet, demonstrated that biodegradation of crystal violet by this fungus is dependent, at least in part, upon its lignin-degrading system. In addition to crystal violet, six other triphenylmethane dyes (pararosaniline, cresol red, bromphenol blue, ethyl violet, malachite green, and brilliant green) were shown to be degraded by the lignin-degrading system of this fungus.

  10. Decolorization of Crystal Violet by ultrasound/heterogeneous Fenton process.

    PubMed

    Zhang, Hui; Gao, Hong; Cai, Chun; Zhang, Chunyang; Chen, Lu

    2013-01-01

    Activated-carbon-supported iron oxides were prepared and used as a catalyst in an integrated ultrasound/heterogeneous Fenton process for the decolorization of Crystal Violet. A synergistic effect was observed when ultrasound was combined with the heterogeneous Fenton process. The decolorization efficiency increased with the increasing power density and catalyst dosage, but decreased with the increase of initial pH value. There exists an optimal hydrogen peroxide concentration for decolorization. Catalyst stability was evaluated by measuring iron leaching in solution. The decolorization efficiency was 88% under the optimal conditions. Toxicity test with Daphnia magna showed that the acute toxicity of dye solution decreased significantly after the treatment by the heterogeneous sono-Fenton process. PMID:24334904

  11. SERS and DFT study of crystal violet

    NASA Astrophysics Data System (ADS)

    Meng, Wei; Hu, Fang; Zhang, Ling-Yan; Jiang, Xiao-Hong; Lu, Lu-De; Wang, Xin

    2013-03-01

    Six silver colloids were prepared by the reduction of silver nitrate with different amounts of sodium citrate. The obtained silver colloids were characterised by UV-vis spectroscopy, transmission electron microscopy and zeta potential measurements. The surface-enhanced Raman scattering (SERS) activities of these silver colloids were investigated using crystal violet (CV) as a SERS probe. Based on density functional theory (DFT) calculations at the level of B3LYP, the Raman spectra and the optimised geometry of CV were analysed. The results show that the sodium citrate content strongly influences the sizes, zeta potentials and SERS activities of the silver colloids. As the sodium citrate content increases in the preparation of silver colloids, the mean diameters of the silver nanoparticles decrease. The most intense SERS of CV on the silver colloids is obtained when 3 mL of 1% sodium citrate is used. CV has D3 point group symmetry, and the Raman vibrational modes belong to A1 or E irreducible representations. The non-totally symmetric vibrational modes E are selectively enhanced in the SERS of CV through a Herzberg-Teller vibronic coupling mechanism, indicating a considerable charge transfer between CV and the silver nanoparticles.

  12. Dichroism and birefringence of natural violet diamond crystals

    SciTech Connect

    Konstantinova, A. F. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)], E-mail: afkonst@ns.crys.ras.ru; Titkov, S. V. [Russian Academy of Sciences, Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry (Russian Federation); Imangazieva, K. B. [Issyk Kul State University (Kyrgyzstan); Evdishchenko, E. A. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Sergeev, A. M. [Karpov Institute of Physical Chemistry, State Scientific Center of the Russian Federation (Russian Federation); Zudin, N. G. [OOO Roni Kerob (Russian Federation); Orekhova, V. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2006-05-15

    Investigation of the optical properties of natural violet diamonds from the Yakutian kimberlites is performed. A red shift of the absorption edge is revealed in the absorption spectra of these crystals. This shift is indicative of the presence of a high concentration of nitrogen in the diamonds studied. Along with the strong band at 0.550 {mu}m, weaker bands at 0.390, 0.456 and 0.496 {mu}m are revealed. It is shown that violet diamond crystals have birefringence and dichroism of about 10{sup -5} and 10{sup -6}, respectively. When a light beam propagates perpendicularly to colored lamellas, the dichroism is much larger and the birefringence is smaller than in the case where the beam direction is parallel to lamellas.

  13. Insight into biosorption equilibrium, kinetics and thermodynamics of crystal violet onto Ananas comosus (pineapple) leaf powder

    NASA Astrophysics Data System (ADS)

    Chakraborty, Sagnik; Chowdhury, Shamik; Saha, Papita Das

    2012-06-01

    Biosorption performance of pineapple leaf powder (PLP) for removal of crystal violet (CV) from its aqueous solutions was investigated. To this end, the influence of operational parameters such as pH, biosorbent dose, initial dye concentration and temperature were studied employing a batch experimental setup. The biosorption process followed the Langmuir isotherm model with high correlation coefficients ( R 2 > 0.99) at different temperatures. The maximum monolayer biosorption capacity was found to be 78.22 mg g-1 at 293 K. The kinetic data conformed to the pseudo-second-order kinetic model. The activation energy of the system was calculated as 58.96 kJ mol- 1 , indicating chemisorption nature of the ongoing biosorption process. A thermodynamic study showed spontaneous and exothermic nature of the biosorption process. Owing to its low cost and high dye uptake capacity, PLP has potential for application as biosorbent for removal of CV from aqueous solutions.

  14. Fast analysis of malachite green, leucomalachite green, crystal violet and leucocrystal violet in fish tissue based on a modified QuEChERS procedure.

    PubMed

    Zhu, Chengyun; Wei, Jie; Dong, Xuefang; Guo, Zhimou; Liu, Mingyang; Liang, Xinmiao

    2014-04-01

    Triphenylmethane dyes malachite green (MG) and crystal violet (CV) have been used as antimicrobial, antiparasitic and antiseptic agents in aquaculture. However, MG and CV, as well as their metabolites leucomalachite green (LMG) and leucocrystal violet (LCV) are potential mutagens and carcinogens. Thus, the efficient determination of dye residues is of great concern. Considering the complexity of the aquatic products, the sample pretreatment is significant for decreasing matrix interference and improving detection sensitivity. In this study, a simple and rapid QuEChERS procedure was developed and combined with HPLC analysis for the simultaneous determination of the four dyes in fish tissue. An XCharge C18 column was applied in HPLC analysis to achieve good peak shape and selectivity. The pretreatment method involved the extraction of dyes from fish tissue and further clean-up with dispersive solid phase extraction (d-SPE) material. The extraction volume, extraction time as well as d-SPE materials were systematically optimized. The results indicated that reversed-phase/strong anion exchange (C18SAX) adsorbent in the d-SPE procedure could effectively improve the recovery compared with conventional C18 or C18 incorporated with primary secondary amine (PSA) material. Under optimized conditions, good linearity was achieved in the concentration range of 0.5-100 mg/L with R2 greater than 0. 998. The recoveries were 73%-91% and the precisions were 0.66%-5.41%. The results demonstrated the feasibility and efficiency of QuEChERS procedure incorporated with HPLC for dye monitoring. PMID:25069333

  15. Post-column reaction for simultaneous analysis of chromatic and leuco forms of malachite green and crystal violet by high-performance liquid chromatography with photometric detection

    USGS Publications Warehouse

    Allen, J.L.; Meinertz, J.R.

    1991-01-01

    The chromatic and leuco forms of malachite green and crystal violet were readily separated and detected by a sensitive and selective high-performance liquid chromatographic procedure. The chromatic and leuco forms of the dyes were separated within 11 min on a C18 column with a mobile phase of 0.05 M sodium acetate and 0.05 M acetic acid in water (19%) and methanol (81%). A reaction chamber, containing 10% PbO2 in Celite 545, was placed between the column and the spectrophotometric detector to oxidize the leuco forms of the dyes to their chromatic forms. Chromatic and leuco malachite green were quantified by their absorbance at 618 nm; and chromatic and leuco Crystal Violet by their absorbance at 588 nm. Detection limits for chromatic and leuco forms of both dyes ranged from 0.12 to 0.28 ng. A linear range of 1 to 100 ng was established for both forms of the dyes.

  16. Batch Removal of Crystal Violet from Aqueous Solution by H2SO4 Modified Sugarcane Bagasse: Equilibrium, Kinetic, and Thermodynamic Profile

    Microsoft Academic Search

    Sagnik Chakraborty; Shamik Chowdhury; Papita Das Saha

    2012-01-01

    Batch adsorption studies were carried out using H2SO4 modified sugarcane bagasse (HMSB) for the removal of hazardous Crystal Violet (CV) dye from aqueous solutions. The effects of initial solution pH, adsorbent dose, and temperature on the adsorption process were investigated. The Langmuir isotherm model well described the equilibrium dye uptake while the pseudo-second-order kinetic model showed good agreement with the

  17. Batch Removal of Crystal Violet From Aqueous Solution by H2SO4 Modified Sugarcane Bagasse: Equilibrium, Kinetic and Thermodynamic Profile

    Microsoft Academic Search

    Sagnik Chakraborty; Shamik Chowdhury; Papita Das Saha

    2012-01-01

    Batch adsorption studies were carried out using H2SO4 modified sugarcane bagasse (HMSB) for removal of hazardous Crystal Violet (CV) dye from aqueous solutions. Effects of initial solution pH, adsorbent dose and temperature on the sorption process were investigated. The Langmuir isotherm model well described the equilibrium dye uptake while the pseudo-second-order kinetic model showed good agreement with the experimental kinetic

  18. BIODEGRADATION OF CRYSTAL VIOLET BY THE WHITE ROT FUNGUS PHANEROCHAETE CHRYSOPORIUM

    EPA Science Inventory

    Biodegradation of crystal violet (N,N,N',N',N",N"-hexamethylpararosaniline) in ligninolytic (nitrogen-limited) cultures of the white rot fungus Phanerochaete chrysosporium was demonstrated by the disappearance of crystal violet and by the identification of three metabolites (N,N,...

  19. Isolation and characterization of Paracoccus sp. GSM2 capable of degrading textile azo dye Reactive Violet 5.

    PubMed

    Bheemaraddi, Mallikarjun C; Patil, Santosh; Shivannavar, Channappa T; Gaddad, Subhashchandra M

    2014-01-01

    A potential bacterial strain GSM2, capable of degrading an azo dye Reactive Violet 5 as a sole source of carbon, was isolated from textile mill effluent from Solapur, India. The 16S rDNA sequence and phenotypic characteristics indicated an isolated organism as Paracoccus sp. GSM2. This strain exhibited complete decolorization of Reactive Violet 5 (100 mg/L) within 16 h, while maximally it could decolorize 800 mg/L of dye within 38 h with 73% decolorization under static condition. For color removal, the most suitable pH and temperature were pH 6.0-9.0 and 25-40 °C, respectively. The isolate was able to decolorize more than 70% of five structurally different azo dyes within 38 h. The isolate is salt tolerant as it can bring out more than 90% decolorization up to a salt concentration of 2% (w/v). UV-Visible absorption spectra before and after decolorization suggested that decolorization was due to biodegradation and was further confirmed by FT-IR spectroscopy. Overall results indicate the effectiveness of the strain GSM2 explored for the treatment of textile industry effluents containing various azo dyes. To our knowledge, this could be the first report on biodegradation of Reactive Violet 5 by Paracoccus sp. GSM2. PMID:24883397

  20. Isolation and Characterization of Paracoccus sp. GSM2 Capable of Degrading Textile Azo Dye Reactive Violet 5

    PubMed Central

    Bheemaraddi, Mallikarjun C.; Shivannavar, Channappa T.; Gaddad, Subhashchandra M.

    2014-01-01

    A potential bacterial strain GSM2, capable of degrading an azo dye Reactive Violet 5 as a sole source of carbon, was isolated from textile mill effluent from Solapur, India. The 16S rDNA sequence and phenotypic characteristics indicated an isolated organism as Paracoccus sp. GSM2. This strain exhibited complete decolorization of Reactive Violet 5 (100?mg/L) within 16?h, while maximally it could decolorize 800?mg/L of dye within 38 h with 73% decolorization under static condition. For color removal, the most suitable pH and temperature were pH 6.0–9.0 and 25–40°C, respectively. The isolate was able to decolorize more than 70% of five structurally different azo dyes within 38 h. The isolate is salt tolerant as it can bring out more than 90% decolorization up to a salt concentration of 2% (w/v). UV-Visible absorption spectra before and after decolorization suggested that decolorization was due to biodegradation and was further confirmed by FT-IR spectroscopy. Overall results indicate the effectiveness of the strain GSM2 explored for the treatment of textile industry effluents containing various azo dyes. To our knowledge, this could be the first report on biodegradation of Reactive Violet 5 by Paracoccus sp. GSM2. PMID:24883397

  1. A study into the mechanism of the Crystal Violet reaction in Staphylococcus aureus.

    PubMed Central

    Barer, M. R.; Burdess, D.; Freeman, R.

    1992-01-01

    The mechanism of the Crystal Violet (CV) reaction, a trait which has been related to biotype, source and pathogenicity in Staphylococcus aureus, was investigated in agar and broth studies. White reactions could be converted to purple and vice versa by altering the incubation conditions on agar. Broth reactions examined macroscopically and by spectrophotometry revealed that both white and purple human biotype strains take up CV but the former then progressively modify the dye more quickly than the latter. A cell-associated product of CV was detected in white and purple strains by reverse-phase thin-layer chromatography of methanol extracts. White strains appear to produce a second additional product from CV. The white reaction was not inhibited by chloramphenicol or azide but did depend on viable cells with a nutrient source. CV MICs and MBCs for 10 white and 10 purple reactors showed no gross differences in susceptibility, while a standardized assay for the rate of CV modifying activity (52 strains) demonstrated that the two categories comprise discrete populations which alter CV at different rates. Although most white strains belong to either or both of phage-typing groups V and II, purple strains with this pattern of susceptibility and white strains without it both occur. The capacity to modify CV slowly or rapidly appears to subdivide human biotype strains independently of their phage group and is associated in the former case with their capacity to produce hospital-acquired and invasive infections. Images Fig. 1 Fig. 2 PMID:1499675

  2. Microwave induced catalytic degradation of crystal violet in nano-nickel dioxide suspensions.

    PubMed

    He, Huan; Yang, Shaogui; Yu, Kai; Ju, Yongming; Sun, Cheng; Wang, Lianhong

    2010-01-15

    Nickel oxide catalyst was obtained by precipitation-oxidation method with the assistance of microwave irradiation. The samples were characterized by X-ray diffraction, Raman spectrophotometer, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, surface area and porosity analyzer. On the basis of the results, the as-prepared product was nano-NiO(2) with OH group and active oxygen. The catalytic activity of the as-prepared product might be attributed to its microwave absorbing property and the role of active oxygen, OH group under microwave irradiation. The microwave induced catalytic degradation process (MICD) with as-prepared product was further applied to degrade triphenylmethane dye crystal violet (CV). 97% of a 100 mg L(-1) sample of CV was rapidly degraded in 5 min with the corresponding 81% TOC removal. The main intermediates were separated and identified by LC-ESI-MS and GC-MS techniques. The LC-ESI-MS analytical results demonstrated that a series of N-de-methylation products were obtained in a stepwise manner, namely mono-, di-, tri-, tetra-, penta-, and hexa-de-methylated CV species. Nine organic acids with benzene ring and four low molecular acids were yielded with the assistance of GC-MS. The proposed degradation pathways were discussed in this study. The degradation processes might include N-de-methylation, destruction of conjugated structure and opening-benzene ring. MICD, as a potential technique with wide application perspective, can be used to purify triphenylmethane dye wastewater with nanosized nickel dioxide. PMID:19748731

  3. Circular dichroic and spectrophotometric probes of the competitive binding of crystal violet between DNA and other anionic polymers

    NASA Astrophysics Data System (ADS)

    Pal, Medini Kanta; Ghosh, Jimut Kanti

    1994-01-01

    Of the two synthetic polyanions poly-(styrene sulfonate) (PSS) and poly-(vinyl sulfate) (PVS), the latter induces sharper metachromasia in the cationic dye crystal violet (CV); DNA, however, fails to induce metachromasia in the dye. Contrary to speculation, DNA binds CV, though a nonintercalating dye, rather strongly and holds a portion of the dye even in the presence of PSS or PVS, which induces strong metachromasia. Induced circular dichroism (ICD) in CV by DNA shows that DNA binds CV, and partial reduction of ellipticity of DNA-CV by PVS shows that CV distributes itself between the two polyanions. DNA is shown to be the winner in the competitive binding of CV even with the strong polyanion heparin (Hep) as the competitor. This has been interpreted as being due to the binding of CV to DNA, primarily by ionic attraction stabilized further by nonionic forces like H-bonding in the grooves of DNA. Quantitative estimations of the association constants of DNA-CV and PVS-CV by Scatchard plot come to 0.74 × 10 6 and 1.28 × 10 6 mol -1, respectively.

  4. Heterogeneous photocatalytic decomposition of Crystal Violet in UV-illuminated sol-gel derived nanocrystalline TiO2 suspensions.

    PubMed

    Senthilkumaar, S; Porkodi, K

    2005-08-01

    Nanostructured TiO2 ultrafine powder (Ti-SG) 100% anatase phase prepared by the sol-gel method was used as a photocatalyst in the decomposition reaction of a basic dye, Crystal Violet (hexamethyl-p-rosaniline chloride), in water under UV light irradiation. Optimization of the photocatalyst's performance as a function of irradiation time, catalyst concentration, and solution pH was performed. The photoactivity was greatly dependent on the solution pH and it was effective for Crystal Violet to be degraded under basic conditions. The extent of photooxidation or -reduction of CV was discussed in terms of the Langmuir-Hinshelwood model. Results also indicated that the proper addition of H2O2 could improve the degradation rate, but excess H2O2 quenched the formation of OH*. Textural and photocatalytic characteristics of sol-gel derived TiO2 (Ti-SG) were compared with those of commercial P25, TiO2. The relative photonic efficiency of sol-gel derived TiO2 was found to be 2.77 with reference to phenol. PMID:15927578

  5. Adsorption of Crystal Violet to the Silica-Water Interface Monitored by Evanescent Wave Cavity Ring-Down Spectroscopy

    E-print Network

    Zare, Richard N.

    a Gouy-Chapman mean-field theory of charged electrode interfaces15 incorporating a localized bindingAdsorption of Crystal Violet to the Silica-Water Interface Monitored by Evanescent Wave Cavity Ring-down spectroscopy (EW-CRDS) has been used to investigate the adsorption of crystal violet (CV+ ) to a charged silica

  6. Modification of the photocatalytic activity of TiO2 by ?-Cyclodextrin in decoloration of ethyl violet dye.

    PubMed

    Velusamy, Ponnusamy; Pitchaimuthu, Sakthivel; Rajalakshmi, Subramanian; Kannan, Nagarathinam

    2014-01-01

    The photocatalytic decoloration of an organic dye, ethyl violet (EV), has been studied in the presence of TiO2 and the addition of ?-Cyclodextrin (?-CD) with TiO2 (TiO2-?-CD) under UV-A light irradiation. The different operating parameters like initial concentration of dye, illumination time, pH and amount of catalyst used have also been investigated. The photocatalytic decoloration efficiency is more in the TiO2-?-CD/UV-A light system than TiO2/UV-A light system. The mineralization of EV has been confirmed by Chemical Oxygen Demand (COD) measurements. The complexation patterns have been confirmed with UV-Visible and FT-IR spectral data and the interaction between TiO2 and ?-CD have been characterized by powder XRD analysis and UV-Visible diffuse reflectance spectroscopy. PMID:25685468

  7. Effectiveness of photochemical and sonochemical processes in degradation of Basic Violet 16 (BV16) dye from aqueous solutions

    PubMed Central

    2012-01-01

    In this study, degradation of Basic Violet 16 (BV16) by ultraviolet radiation (UV), ultrasonic irradiation (US), UV/H2O2 and US/H2O2 processes was investigated in a laboratory-scale batch photoreactor equipped with a 55W immersed-type low-pressure mercury vapor lamp and a sonoreactor with high frequency (130kHz) plate type transducer at 100W of acoustic power. The effects of initial dye concentration, concentration of H2O2 and solution pH and presence of Na2SO4 was studied on the sonochemical and photochemical destruction of BV16 in aqueous phase. The results indicated that in the UV/H2O2 and US/H2O2 systems, a sufficient amount of H2O2 was necessary, but a very high H2O2 concentration would inhibit the reaction rate. The optimum H2O2 concentration was achieved in the range of 17 mmol/L at dye concentration of 30 mg/L. A degradation of 99% was obtained with UV/H2O2 within 8 minutes while decolorization efficiency by using UV (23%), US (<6%) and US/H2O2(<15%) processes were negligible for this kind of dye. Pseudo-first order kinetics with respect to dyestuffs concentrations was found to fit all the experimental data. PMID:23369268

  8. Adsorptionof fast green and erythrosin-B to montmorillonite modified with crystal violet

    Microsoft Academic Search

    G. Rytwo; R. Huterer-Harari; S. Dultz; Y. Gonen

    2006-01-01

    Adsorption\\u000a of erythrosin-B (EB) and fast green (FG) to a non-charged organosmectite based\\u000a on crystal violet adsorbed up to 100% of the cation exchange capacity (CEC)\\u000a was tested. Adsorption isotherms of EB and FG were prepared at 3, 24 and 50C.\\u000a All isotherms are of H-type reaching loads of approximately up to 20% of the\\u000a original CEC of the crude

  9. Pathways of reductive degradation of crystal violet in wastewater using free-strain Burkholderia vietnamiensis C09V.

    PubMed

    Gan, Li; Cheng, Ying; Palanisami, Thavamani; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

    2014-09-01

    A new strain isolated from activated sludge and identified as Burkholderia vietnamiensis C09V was used to biodegrade crystal violet (CV) from aqueous solution. To understand the degradation pathways of CV, batch experiments showed that the degradation using B. vietnamiensis C09V significantly depended on conditions such as pH, initial dye concentration and media components, carbon and nitrogen sources. Acceleration in the biodegradation of CV was observed in presence of metal ions such as Cd and Mn. More than 98.86C of CV (30 mg l(-1)) was degraded within 42 h at pH 5 and 30 °C. The biodegradation kinetics of CV corresponded to the pseudo first-order rate model with a rate constant of 0.046 h(-1). UV-visible and Fourier transform infrared spectroscopy (FTIR) were used to identify degradation metabolites. Which further confirmed by LC-MS analysis, indicating that CV was biodegraded to N,N-dimethylaminophenol and Michler's ketone prior to these intermediates being further degraded. Finally, the ability of B. vietnamiensis C09V to remove CV in wastewater was demonstrated. PMID:24862483

  10. Nanoimprinted polymer photonic crystal dye lasers

    NASA Astrophysics Data System (ADS)

    Christiansen, Mads B.; Smith, Cameron L. C.; Buss, Thomas; Xiao, Sanshui; Mortensen, Niels A.; Kristensen, Anders

    2010-05-01

    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). The lasers are fabricated in parallel on a 10 cm diameter wafer by combined nanoimprint and photolithography (CNP). CNP relies on a UV transparent quartz nanoimprint stamp with an integrated metal shadow mask. In the CNP process the photonic crystal is formed by mechanical deformation (imprinting) while the larger features are defined by UV exposure through the combined mask/mold.

  11. Rapid reversible phototuning of lasing frequency in dye-doped cholesteric liquid crystal.

    PubMed

    Mykytiuk, T V; Ilchishin, I P; Yaroshchuk, O V; Kravchuk, R M; Li, Y; Li, Q

    2014-11-15

    Lasing in induced cholesteric liquid crystal (CLC) containing highly photosensitive azo chiral dopant (ChD) and pyrromethene laser dye was investigated. Due to the absence of excitation energy transfer from the dye molecules to the molecules of ChD in such a system, a low lasing threshold was achieved. When using violet and green light-emitting diodes, reversible frequency tuning was obtained in the range of about 30 nm with a tuning time 1-2 orders of magnitude smaller than in conventional CLC laser systems based on azo and azoxy photosensitive compounds. Further increase of the intensity of the excitation light by using a green laser pointer allowed us to achieve a record phototuning speed (?21??nm in 148 ms). PMID:25490501

  12. Synthesis and characterisation of potassium polytitanate for photocatalytic degradation of crystal violet.

    PubMed

    Shahid, Mohammad; El Saliby, Ibrahim; McDonagh, Andrew; Tijing, Leonard D; Kim, Jong-Ho; Shon, Ho Kyong

    2014-11-01

    Potassium titanate nanostructures were synthesised by hydrothermal treatment of TiO2 (P25) in KOH and H2O2. As-produced powders were characterised by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, and nitrogen adsorption-desorption methods. Longitudinally-oriented-wire-like structures with a length up to several micrometres and diameters ranging from 10 to 30 nm were obtained. Larger size fibrous nanowires resulting from the hydrothermal treatment showed high affinity in adsorbing crystal violet (CV), which was mainly due to their high surface area. The photocatalytic bleaching of CV solution revealed that the wires are photoactive under ultraviolet light irradiation. Macroporous nanowires are considered as effective adsorbents of CV, capable of photocatalytic degradation, and they can be easily separated from the solution by settling. PMID:25458691

  13. Adsorption of basic dyes from aqueous solution onto pumice powder

    Microsoft Academic Search

    Feryal Akbal

    2005-01-01

    The adsorption of methylene blue and crystal violet on pumice powder samples of varying compositions was investigated using a batch adsorption technique. The effects of various experimental parameters, such as adsorbent dosage, initial dye concentration, and contact time, were also investigated. The extent of dye removal increased with decreased initial concentration of the dye and also increased with increased contact

  14. Photoexcited azo-dye induced torque in nematic liquid crystals

    Microsoft Academic Search

    B. Saad; T. V. Galstyan; M. M. Denariez-Roberge; M. Dumont

    1998-01-01

    We study molecule reorientation initiated by absorption of resonant light, in D2 azo dye doped nematic liquid crystals. The photoexcitation of the dye subsystem creates a torque on the host, that is not collinear with the traditional dielectric torque. The temporal and geometrical characteristics of these torques are also different. Transient three dimensional molecular reorientation is detected through different paths

  15. Use of hydrogen peroxide treatment and crystal violet agar plates for selective recovery of bacteriophages from natural environments

    SciTech Connect

    Asghari, A.; Farrah, S.R.; Bitton, G. (Univ. of Florida, Gainesville (United States))

    1992-04-01

    Hydrogen peroxide inactivated bacteriophages and bacteria at different rates. A concentration of 0.1% hydrogen peroxide reduced the numbers of several bacteria by an average of 94% but caused an average of 25% inactivation in the numbers of bacteriophages tested. Treating natural samples with hydrogen peroxide selectively reduced the indigenous bacterial flora and permitted better visualization of plaques of lawns of Escherichia coli C-3000. In some cases indigenous gram-positive bacteria were relatively resistant to hydrogen peroxide, but their growth could be limited by incorporation of crystal violet into the bottom agar used for plaque assays. The use of hydrogen peroxide treatment and crystal violet-containing plates permitted recovery of more phages from natural samples than did other procedures, such as chloroform pretreatment or the use of selective plating agar such as EC medium.

  16. Determination of polyhexamethylene biguanide hydrochloride using photometric colloidal titration with crystal violet as a color indicator.

    PubMed

    Masadome, Takashi; Miyanishi, Takaaki; Watanabe, Keita; Ueda, Hiroshi; Hattori, Toshiaki

    2011-01-01

    A solution of polyhexamethylene biguanide hydrochloride (PHMB-HCl) was titrated with a standard solution of potassium poly(vinyl sulfate) (PVSK) using crystal violet (CV) as an photometric indicator cation. The end point was detected by a sharp absorbance change due to an abrupt decrease in the concentration of CV. A linear relationship between the concentration of PHMB-HCl and the end-point volume of the titrant existed in the concentration range from 2 to 10 × 10(-6) eq mol L(-1). Back-titration was based on adding an excess amount of PVSK to a sample solution containing CV, which was titrated with a standard solution of poly(diallyldimethylammonium chloride) (PDADMAC). The calibration curve of the PHMB-HCl concentration to the end point volume of the titrant was also linear in the concentration range from 2 to 8 × 10(-6) eq mol L(-1). Both photometric titrations were applied to the determination of PHMB-HCl in a few contact-lens detergents. Back-titration showed a clear end point, but direct titration showed an unclear end point. The results of the back-titration of PHMB-HCl were compared with the content registered in its labels. PMID:21828919

  17. Leuco-crystal-violet micelle gel dosimeters: II. Recipe optimization and testing

    NASA Astrophysics Data System (ADS)

    Nasr, A. T.; Alexander, K. M.; Olding, T.; Schreiner, L. J.; McAuley, K. B.

    2015-06-01

    In this study, recipe optimization of Leuco Crystal Violet (LCV) micelle gels made with the surfactant Cetyl Trimethyl Ammonium Bromide (CTAB) and the chemical sensitizer 2,2,2-trichloroethanol (TCE) was aided by a two-level three-factor designed experiment. The optimized recipe contains 0.75?mM LCV, 17.0?mM CTAB, 120?mM TCE, 25.0?mM tri-chloro acetic acid (TCAA), 4?wt% gelatin and ~96?wt% water. Dose sensitivity of the optimized gel is 1.5 times higher than that of Jordan’s standard LCV micelle gel. Spatial integrity of the 3D dose distribution information in 1L phantoms filled with this recipe is maintained for??>120?d. Unfortunately, phantoms made using the optimized recipe showed dose-rate dependence (14% difference in optical attenuation at the peak dose using electron beam irradiations at 100 and 400?MU?min?1). Further testing suggests that the surfactant CTAB is the cause of this dose rate behaviour.

  18. Leuco-crystal-violet micelle gel dosimeters: I. Influence of recipe components and potential sensitizers

    NASA Astrophysics Data System (ADS)

    Nasr, A. T.; Alexander, K.; Schreiner, L. J.; McAuley, K. B.

    2015-06-01

    Radiochromic leuco crystal violet (LCV) micelle gel dosimeters are promising three-dimensional radiation dosimeters because of their spatial stability and suitability for optical readout. The effects of surfactant type and surfactant concentration on dose sensitivity of LCV micelle gels are tested, demonstrating that dose sensitivity and initial colour of the gel increases with increasing Triton x-100 (Tx100) concentration. Using Cetyl Trimethyl Ammonium Bromide (CTAB) in place of Tx100 produces gels that are nearly colourless prior to irradiation, but reduces the dose sensitivity. The separate effects of Tri-chloro acetic acid concentration and pH are investigated, revealing that controlling the pH near 3.6 is crucial for achieving high dose sensitivity. The sensitizing effect of chlorinated species on dose sensitivity is tested using 2,2,2-trichloroethanol (TCE), chloroform, and 1,1,1-trichloro-2-methyl-2-propanol hemihydrate. TCE gives the largest improvement in dose sensitivity and is recommended for use in micelle gel dosimeters because it is less volatile and safer to use than chloroform. Preliminary experiments on a new gel containing CTAB as the surfactant and TCE show that this new gel gives a dose sensitivity that is 24% higher than that of previous LCV micelle gels and is nearly colourless prior to irradiation.

  19. Application of LC-MS and LC-MS-MS to the analysis of photo-decomposed crystal violet in the investigation of cultural heritage materials aging.

    PubMed

    Favaro, Gabriella; Confortin, Daria; Pastore, Paolo; Brustolon, Marinarosa

    2012-12-01

    In this work, the accurate liquid chromatography-ultraviolet-visible (LC-UV-Vis), LC-mass spectrometry (MS) and LC-MS-MS analysis of the photo-degradation products of crystal violet (CV) is reported. CV is a light fugitive early synthetic dye which had a widespread diffusion into the market starting from the end of the XIX century and was used among others by V. Van Gogh and P. Gauguin in their writings, drawings or paintings. On-line photodiode array detector enabled simultaneous UV-Vis spectra acquisition. Many degradation compounds were identified through their exact mass (2?ppm accuracy) and MS-MS technique. In particular, all CV demethylated products, demethylated Michler's ketone and particularly some compounds that most likely contain oxygen, such as N-oxides, were found. Fragmentation products are all justified by the proposed fragmentation scheme, in term of precursor exact mass and isotopic profile, characteristic losses in fragmentation and rebuilt structure formula. In particular, we hypothesized the presence of N-imido oxides and hydroxylamine derivates, never reported before, together with the demethylated derivatives of the studied dyes. All these compounds, although at trace level in our samples, contribute to the discoloration and fading of works of arts made with CV. In particular, demethylation of CV by UV light leads to formation of compounds absorbing at shorter wavelengths than CV (blue shift) or no-absorbing in visible range (yellow-colourless) with an overall effect that may appear reddish-brown. This phenomenon justifies drawings appearing grey or brown on aged yellowed paper, when CV-based inks or paints were used. The final aim was to better characterize the photo-degradation of early synthetic dyes (in particular of CV) and to gain a better insight into the discoloration and fading of purple ink strokes made of CV. PMID:23280755

  20. Growth, dye degradation and ligninolytic activity studies on Zimbabwean white rot fungi

    Microsoft Academic Search

    M Tekere; A. Y Mswaka; R Zvauya; J. S Read

    2001-01-01

    White rot fungi were collected from Chirinda and Chimanimani hardwood forests in Zimbabwe and studied with respect to growth temperature optima and dye decolorization. Temperature optima were found to vary (between 25–37°C) amongst the isolates. The isolates were screened for their ability to degrade the polymeric dyes; blue dextran and Poly R478 and the triphenylmethane dyes; cresol red, crystal violet

  1. Crystal violet staining of Bordetella bronchiseptica colonies for differentiation of phase-I strains from variant strains in degraded phases.

    PubMed Central

    Ishikawa, H; Isayama, Y

    1997-01-01

    After 2 days of growth on Brain heart infusion agar (BHIA) at 38 degrees C, phase-I colonies and degraded-phase colonies of Bordetella bronchiseptica could be differentiated by their ability to take up crystal violet (CV). Phase-I colonies in X mode, but not colonies in degraded phases (phases II, III, and rough) bound CV. Phenotypically-altered C-mode colonies (grown at 32 degrees C or lower temperatures) also lacked this ability. CV staining offers an easy method for the recognition of different colony types that appear identical when observed on BHIA. Images Figure 1. Figure 2. PMID:9243005

  2. Aggregation behavior and chromonic liquid crystal properties of an anionic monoazo dye Viva R. Horowitz,1

    E-print Network

    Collings, Peter

    Aggregation behavior and chromonic liquid crystal properties of an anionic monoazo dye Viva R the aggregation process and chromonic liquid crystal phase of the anionic monoazo dye Sunset Yellow FCF. The x undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye

  3. An alternative staining method for counting red-eared slider turtle (Trachemys scripta) blood cells using crystal violet in cells diluted with 0.45% sodium chloride.

    PubMed

    Tsai, Chyong-Ying; Yu, Jane-Fang; Wang, Yu-Wen; Fan, Pei-Chia; Cheng, Ting-Yu; Wang, Lih-Chiann

    2014-09-01

    Various staining methods are available for reptilian species blood cell quantification. However, these methods have shown inaccurate differentiation limitations. The current study evaluates staining effects and blood cell counting results using an alternative method, counting blood cells diluted with 0.45% sodium chloride solution and stained with crystal violet. Blood samples from 8 red-eared slider turtles (Trachemys scripta) were collected. Red and white blood cell counts were performed using different methods: the unstained method, the Unopette method, Liu stain, and crystal violet method using blood cells diluted in various sodium chloride solution osmolarities. The staining properties and blood cell count results were compared. The crystal violet method using blood cells diluted in 0.45% sodium chloride solution delivered the best staining and counting results among all of the tested methods, with the lowest average coefficient of variance. The proposed method can easily be performed, serving as a feasible method for blood cell counting in chelonians. PMID:25080443

  4. Photoluminescence analysis of self induced planer alignment in azo dye dispersed nematic liquid crystal complex

    SciTech Connect

    Kumar, Rishi, E-mail: kkraina@gmail.com; Sood, Srishti, E-mail: kkraina@gmail.com; Raina, K. K., E-mail: kkraina@gmail.com [School of Physics and Materials Science, Thapar University, Patiala-147004 (India)

    2014-04-24

    We have developed azo dye doped nematic liquid crystal complex for advanced photonic liquid crystal display technology aspects. Disperse orange azo dye self introduced planer alignment in the nematic liquid crystal without any surface anchoring treatment. Planer alignment was characterized by optical polarizing microscopy. The electro-optical switching response of dye disperse planer aligned nematic cell was investigated as a function of applied voltage with the help of photoluminescence spectrophotometer for the tuning of photoluminescence contrast.

  5. Synthesis, linear optical, non-linear optical, thermal and mechanical characterizations of dye-doped semi-organic NLO crystals

    NASA Astrophysics Data System (ADS)

    Sesha Bamini, N.; Vidyalakshmy, Y.; Choedak, Tenzin; Kejalakshmy, N.; Muthukrishnan, P.; Ancy, C. J.

    2015-06-01

    Organic laser dyes Coumarin 485, Coumarin 540 and Rhodamine 590 Chloride were used to dope potassium acid phthalate crystals (KAP). Dye-doped KAP crystals with different dye concentrations such as 0.01 mM, 0.03 mM, 0.05 mM, 0.07 mM and 0.09 mM (in the KAP growth solution) were grown. The linear optical, non-linear optical, mechanical and thermal characterizations of dye-doped KAP crystals were studied and compared to understand the effect of dye and dye concentration on the KAP crystal. Absorption and emission studies of KAP and dye-doped KAP single crystals indicated the inclusion of the dye into the KAP crystal lattice. The effect of dye and its concentration on the SHG efficiency of the KAP crystal was studied using the Kurtz and Perry powder technique. It was observed that the absorption maximum wavelength and concentration of the dye used for doping the KAP single crystal decided the SHG efficiency of the dye-doped KAP single crystals. The mechanical hardness of the dye-doped and undoped (pure) KAP single crystals were studied using the Vickner’s microhardness test. It was observed that doping the KAP crystals with the laser dyes changed them from softer material to harder material. Etching studies showed an improvement in the optical quality of the KAP crystal after doping with laser dyes.

  6. Extractive biodecolorization of triphenylmethane dyes in cloud point system by Aeromonas hydrophila DN322p.

    PubMed

    Pan, Tao; Ren, Suizhou; Xu, Meiying; Sun, Guoping; Guo, Jun

    2013-07-01

    The biological treatment of triphenylmethane dyes is an important issue. Most microbes have limited practical application because they cannot completely detoxicate these dyes. In this study, the extractive biodecolorization of triphenylmethane dyes by Aeromonas hydrophila DN322p was carried out by introducing the cloud point system. The cloud point system is composed of a mixture of nonionic surfactants (20 g/L) Brij 30 and Tergitol TMN-3 in equal proportions. After the decolorization of crystal violet, a higher wet cell weight was obtained in the cloud point system than that of the control system. Based on the results of thin-layer chromatography, the residual crystal violet and its decolorized product, leuco crystal violet, preferred to partition into the coacervate phase. Therefore, the detoxification of the dilute phase was achieved, which indicated that the dilute phase could be discharged without causing dye pollution. The extractive biodecolorization of three other triphenylmethane dyes was also examined in this system. The decolorization of malachite green and brilliant green was similar to that of crystal violet. Only ethyl violet achieved a poor decolorization rate because DN322p decolorized it via adsorption but did not convert it into its leuco form. This study provides potential application of biological treatment in triphenylmethane dye wastewater. PMID:23008002

  7. Photobleaching and reorientational dynamics of dyes in a nematic liquid crystal M. Nollmann and D. Shalom

    E-print Network

    Nollmann, Marcelo

    results with the mean-field Maier-Saupe theory of the nematic state are presented, and a model is proposedPhotobleaching and reorientational dynamics of dyes in a nematic liquid crystal M. No¨llmann and D Received 25 August 1998 The polarized fluorescence of excited dyes in a prototype nematic liquid crystal

  8. Aggregation in Two Dye Systems That Form Chromonic Liquid Crystals

    NASA Astrophysics Data System (ADS)

    Collings, Peter J.; Horowitz, Viva R.; Tomasik, Michelle R.

    2006-03-01

    X-ray scattering and various optical techniques are utilized to study the aggregation process and aggregate structure for two water-soluble dyes that form chromonic liquid crystal phases. The x-ray measurements indicate that the molecules stack in columns with a cross-section approximately equal to the area of a single molecule. The optical measurements point to an aggregation process that occurs at all concentrations, with the distribution of aggregate size shifting to larger and larger aggregates as the concentration is increased. A simple theory based on the law of mass action and an isodesmic aggregation process is in excellent agreement with the experimental data, yielding a value for the ``bond energy'' between the molecules in an aggregate.

  9. Experimental Investigation of Laser Emission of Dye-Doped Cholesteric Liquid Crystals with a

    E-print Network

    Wu, Shin-Tson

    like a one-dimensional photo- nic crystal laser when pumped by a second harmonic Nd-YAG pulsed laser; laser enhancement 1. INTRODUCTION Cholesteric liquid crystal (CLC) is a promising chiral photonic mediumExperimental Investigation of Laser Emission of Dye-Doped Cholesteric Liquid Crystals

  10. Imposed Orientation of Dye Molecules by Liquid Crystals and an Electric Field.

    ERIC Educational Resources Information Center

    Sadlej-Sosnowska, Nina

    1980-01-01

    Describes experiments using dye solutions in liquid crystals in which polar molecules are oriented in an electrical field and devices are constructed to change their color in response to an electric signal. (CS)

  11. 27 CFR 21.111 - Gentian violet.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...violet (methyl violet, methylrosaniline chloride) occurs as a dark green powder or crystals having metallic luster. (b) Arsenic...brown, then to green, and finally to blue. (d) Insoluble matter. Not to exceed 0.25 percent when tested by the...

  12. 27 CFR 21.111 - Gentian violet.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...violet (methyl violet, methylrosaniline chloride) occurs as a dark green powder or crystals having metallic luster. (b) Arsenic...brown, then to green, and finally to blue. (d) Insoluble matter. Not to exceed 0.25 percent when tested by the...

  13. 27 CFR 21.111 - Gentian violet.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...violet (methyl violet, methylrosaniline chloride) occurs as a dark green powder or crystals having metallic luster. (b) Arsenic...brown, then to green, and finally to blue. (d) Insoluble matter. Not to exceed 0.25 percent when tested by the...

  14. 27 CFR 21.111 - Gentian violet.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...violet (methyl violet, methylrosaniline chloride) occurs as a dark green powder or crystals having metallic luster. (b) Arsenic...brown, then to green, and finally to blue. (d) Insoluble matter. Not to exceed 0.25 percent when tested by the...

  15. Photoelectrochemical Characteristic of ZnO Dye-sensitized Solar Cell with Platinum Nanoparticle as a Counterelectrode

    Microsoft Academic Search

    Pipat Ruankham; Chaiyut Sae-kung; Nikorn Mangkorntong; Pongsri Mangkorntong; Supab Choopun

    Photoelectrochemical characteristic of ZnO dye-sensitized solar cell (DSSC) with platinum nanoparticle as a counterelectrode was studied. The structure of the DSSC was FTO\\/ZnO\\/dye\\/electrolyte\\/Pt nanoparticle counter- electrode. For types of dye, Eosin-Y, Rhodamine B and Crystal Violet were examined as sensitizers for ZnO DSSC. The photoelectrochemical characteris- tics were measured under illumination of simulated sunlight came from a solar simulator with

  16. Lasing in DyeDoped Photonic Liquid Crystal Devices Yuhua Huang

    E-print Network

    Wu, Shin-Tson

    of the refractive index and consequently offers a one-dimensional (1D) photonic band gap with the central wavelengthLasing in Dye­Doped Photonic Liquid Crystal Devices Yuhua Huang Ying Zhou Shin-Tson Wu College and the incident angle is normal to the sample. Keywords: cholesteric liquid crystal; laser; lasing efficiency

  17. Dye-doped cholesteric-liquid-crystal room-temperature single-photon source

    SciTech Connect

    Lukishova, S.G.; Schmid, A.W.; Supranowitz, C.M.; Lippa, N.; McNamara, A.J.; Boyd, R.W.; Stroud, Jr., C.R.

    2004-06-15

    Fluorescence antibunching from single terrylene molecules embedded in a cholesteric-liquid-crystal host is used to demonstrate operation of a room-temperature single-photon source. One-dimensional (1-D) photonic-band-gap microcavities in planar-aligned cholesteric liquid crystals with band gaps from visible to near-infrared spectral regions are fabricated. Liquid-crystal hosts (including liquid crystal oligomers and polymers) increase the source efficiency, firstly, by aligning the dye molecules along the direction preferable for maximum excitation efficiency (deterministic molecular alignment provides deterministically polarized output photons), secondly, by tuning the 1-D photonic-band-gap microcavity to the dye fluorescence band and thirdly, by protecting the dye molecules from quenchers, such as oxygen.

  18. Phenylazoindole dyes - Part I: The syntheses, characterizations, crystal structures, quantum chemical calculations and antimicrobial properties

    NASA Astrophysics Data System (ADS)

    Sefero?lu, Zeynel; Yalç?n, Ergin; Babür, Banu; Sefero?lu, Nurgül; Hökelek, Tuncer; Y?lmaz, Ebru; ?ahin, Ertan

    2013-09-01

    In this study, the synthesis of four new phenylazo indole dyes (dye 1-4) were carried out by diazotization of 4-aminoacetophenone and coupling with various 2- and 1,2-disubstituted indole derivatives. The dyes were characterized by UV-vis, FT-IR, 1H NMR, HRMS and X-ray single crystal diffraction methods. Azo-hydrazone tautomeric bahavior of the dyes in different solvents (DMSO, methanol, acetic acid and chloroform) was investigated by using 1H NMR and UV-vis results. The experimental results were compared with the corresponding calculated values. The results of experimental data and theoretical calculations showed that the azo tautomer is more stable than hydrazone tautomer. In addition to this, the antimicrobial activity of the dyes was also evaluated.

  19. Increasing the Conversion Efficiency of Dye-Sensitized TiO2 Photoelectrochemical Cells by Coupling to Photonic Crystals

    E-print Network

    The mechanism of enhancing the light harvesting efficiency of dye-sensitized TiO2 solar cells by coupling TiO2Increasing the Conversion Efficiency of Dye-Sensitized TiO2 Photoelectrochemical Cells by Coupling to conventional single-crystal solar cells. In this cell, an optically excited dye injects electrons

  20. Removal of acid dye (violet 54) and adsorption kinetics model of using musa spp. waste: A low-cost natural sorbent material

    Microsoft Academic Search

    G. Vijaya Kumar; P. Ramalingam; Min Jung Kim; Chang Kyoo Yoo; M. Dharmendira Kumar

    2010-01-01

    Experimental studies and biosorption kinetics of an intraparticle diffusion model for acid dye removal using a musa spp. waste\\u000a sorbent were carried out to find the removal effects and dynamics of various operating parameters, such as initial dye concentration,\\u000a sorbent dosage, pH and temperature. Experimental data were modeled with kinetic models and two biosorption isotherms of intraparticle\\u000a diffusion models as

  1. Spatially tunable laser emission in dye-doped photonic liquid crystals Yuhua Huang, Ying Zhou, and Shin-Tson Wua

    E-print Network

    Wu, Shin-Tson

    laser emission of the dye-doped cholesteric liquid crystal CLC cell using a one-dimensional temperatureSpatially tunable laser emission in dye-doped photonic liquid crystals Yuhua Huang, Ying Zhou a periodic modulation of the refractive index. Conse- quently, a one-dimensional photonic band gap PBG is es

  2. Enhancement of the fluorescence of triphenylmethane dyes caused by their interaction with nanoparticles from ?-diketonate complexes

    NASA Astrophysics Data System (ADS)

    Sveshnikova, E. B.; Ermolaev, V. L.

    2014-08-01

    We have studied the absorption and fluorescence spectra of Malachite Green and Crystal Violet in aqueous and alcoholic-aqueous solutions in which nanoparticles from Ln(III) and Sc(III) diketonates are formed at concentrations of complexes in a solution of 5-30 ?M. We have shown that, if the concentrations of the dyes in the solution are lower than 0.5 ?M, dye molecules are incorporated completely into nanoparticles or are precipitated onto their surface. The fluorescence intensity of these incorporated and adsorbed Malachite Green and Crystal Violet molecules increases by several orders of magnitude compared to the solution, which takes place because of a sharp increase in the fluorescence quantum yields of these dyes and at the expense of the sensitization of their fluorescence upon energy transfer from ?-diketonate complexes entering into the composition of nanoparticles. We have shown that, if there is no concentration quenching, the values of the fluorescence quantum yield of the Crystal Violet dye incorporated into nanoparticles and adsorbed on their surface vary from 0.06 to 0.13, i.e., are close to the fluorescence quantum yield of this dye in solid solutions of sucrose acetate at room temperature. The independence of the fluorescence quantum yield of Crystal Violet on the morphology of nanoparticles testifies to a high binding constant of complexes and the dye. The considerable fluorescence quantum yields of triphenylmethane dyes in nanoparticles and sensitization of their fluorescence by nanoparticle-forming complexes make it possible to determine the concentration of these dyes in aqueous solutions by the luminescent method in the range of up to 1 nM.

  3. Crystal formation involving 1-methylbenzimidazole in iodide\\/triiodide electrolytes for dye-sensitized solar cells

    Microsoft Academic Search

    Andreas Fischer; Henrik Pettersson; Anders Hagfeldt; Gerrit Boschloo; Lars Kloo; Mikhail Gorlov

    2007-01-01

    Nitrogen heterocyclic compounds, such as N-methylbenzimidazole (MBI), are commonly used as additives to electrolytes for dye-sensitized solar cells (DSCs), but the chemical transformation of additives in electrolyte solutions remains poorly understood. Solid crystalline compound (MBI)6(MBI-H+)2(I?)(I3?) (1) was isolated from different electrolytes for DSCs containing MBI as additive. The crystal structure of 1 was determined by single-crystal X-ray diffraction. In the

  4. Biodecolorization of acid violet 19 by Alternaria solani

    Microsoft Academic Search

    Hazrat Ali; Shah Khalid Muhammad

    Microorganisms are the nature's tools for cleaning the environment. Bioremediation using bacteria, fungi and algae is becoming an attractive option for the treatment of industrial effluents containing a wide spectrum of pollutants including dyes and heavy metal ions. In the current research work, the potential of a deuteromycete fungus, Alternaria solani for the removal of a dye, Acid Violet 19

  5. Optically switchable grating based on dye-doped ferroelectric liquid crystal with high efficiency.

    PubMed

    Kim, Jiyoon; Suh, Jeng-Hun; Lee, Bo-Yeon; Kim, Se-Um; Lee, Sin-Doo

    2015-05-18

    We demonstrate an all-optically switchable ferroelectric liquid crystal (FLC) grating constructed in an alternating binary configuration with different optical properties from domain to domain. A dye-doped FLC is uniformly aligned in one type of domains whereas it is infiltrated into the photo-polymerized networks of reactive mesogens in the other. Compared to conventional nematic LC cases, our FLC grating allows more efficient all-optical modulation and faster diffraction switching between the 0th and the 1st orders in subsecond since the optical response associated with the dye molecules in the layered state is less hindered than in the orientationally ordered state. Our dye-doped FLC grating with periodically infiltrated structures will be useful for designing a new class of all-optically switching systems. PMID:26074517

  6. Controlled hydrothermal synthesis of BiOxCly/BiOmIn composites exhibiting visible-light photocatalytic degradation of crystal violet.

    PubMed

    Jiang, Yu-Rou; Lin, Ho-Pan; Chung, Wen-Hsin; Dai, Yong-Ming; Lin, Wan-Yu; Chen, Chiing-Chang

    2015-02-11

    A series of BiOxCly/BiOmIn composites were prepared using autoclave hydrothermal methods. The composition and morphologies of the BiOxCly/BiOmIn composites were controlled by adjusting the experimental conditions: the reaction pH value, temperature, and KCl/KI molar ratio. The products were characterized using X-ray diffraction, scanning electron microscopy-electron dispersive X-ray spectroscopy, UV-vis diffuse reflectance spectroscopy, Brunauer-Emmett-Teller specific surface areas, cathodoluminescence, high-resolution transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. The photocatalytic efficiencies of composite powder suspensions were evaluated by monitoring the crystal violet (CV) concentrations. In addition, the quenching effects of various scavengers indicated that the reactive O2(-) played a major role, and OH or h(+) played a minor role in CV degradation. The intermediates formed during the decomposition process were isolated, identified, and characterized using high performance liquid chromatography-photodiode array-electrospray ionization-mass spectrometry to elucidate the CV decomposition mechanism. PMID:25464322

  7. Synthesis of core-shell SiO2@MgO with flower like morphology for removal of crystal violet in water.

    PubMed

    Pei, Yanyan; Wang, Man; Tian, Di; Xu, Xuefeng; Yuan, Liangjie

    2015-09-01

    In this study, we report a facile and effective route to synthesize core-shell SiO2@MgO with flower like morphology, which the shell is assembled by magnesium oxide nanosheets. The SiO2@MgO composite (SMC) was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectrometry (EDX), X-ray fluorescence (XRF) and N2 adsorption-desorption techniques. The sample showed excellent performance for the removal of crystal violet due to its high specific surface area and porous structures. Adsorption data fitted better with Langmuir isotherm and the maximum adsorption capacity was 2244.85mgg(-1). The kinetic data was better described by pseudo-second order model and thermodynamic studies showed that adsorption process was spontaneous and endothermic. The adsorbent also showed very good reproducibility and reusability for the successive five cycles, indicating a promising potential material for environmental remediation. PMID:25985423

  8. Molecular Assembly and Liquid Crystal Properties of a Near-IR Absorbing Dye

    NASA Astrophysics Data System (ADS)

    Collings, Peter; Mills, Elizabeth

    2012-02-01

    The molecules of the near-IR absorbing dye IR-806 spontaneously assemble in water at very low concentrations, forming a liquid crystal phase at room temperature when the concentration is above 0.6 wt%. Unlike most chromonic liquid crystal systems, macroscopic phase separation between the isotropic and liquid crystal phases is not observed. Also unlike most chromonic liquid crystal systems, the absorption spectrum of IR-806 changes dramatically as the concentration increases and molecular assembly proceeds. Analysis of the absorption spectra provides evidence of an isodesmic assembly process at an extremely low concentration, followed by a second non-isodesmic assembly process at a higher concentration just before the liquid crystal phase appears.

  9. Anisotropic photonic structures induced by three-dimensional vector holography in dye-doped liquid crystals

    Microsoft Academic Search

    Tomoyuki Sasaki; Hiroshi Ono; Nobuhiro Kawatsuki

    2008-01-01

    Periodic anisotropic structures were induced by means of a three-dimensional vector holographic technique in an azo-dye-doped liquid crystal composite with uniaxial alignment. The three-dimensional vector hologram was fabricated by both the polarization interference and the polarization propagation in the anisotropic recording medium. In order to obtain clear insight into the optical properties of three-dimensional vector holograms, various types of structures

  10. Aggregation behavior and chromonic liquid crystal properties of an anionic monoazo dye

    NASA Astrophysics Data System (ADS)

    Horowitz, Viva R.; Janowitz, Lauren A.; Modic, Aaron L.; Heiney, Paul A.; Collings, Peter J.

    2005-10-01

    X-ray scattering and various optical techniques are utilized to study the aggregation process and chromonic liquid crystal phase of the anionic monoazo dye Sunset Yellow FCF. The x-ray results demonstrate that aggregation involves ?-? stacking of the molecules into columns, with the columns undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye concentration. Optical absorption measurements on dilute solutions reveal that the aggregation takes place at all concentrations, with the average aggregation number increasing with concentration. A simple theory based on the law of mass action and an isodesmic aggregation process is in excellent agreement with the experimental data and yields a value for the “bond” energy between molecules in an aggregate. Measurements of the birefringence and order parameter are also performed as a function of temperature in the chromonic liquid crystal phase. The agreement between these results and a more complicated theory of aggregation is quite reasonable. Overall, these results both confirm that the aggregation process for some dyes is isodesmic and provide a second example of a well-characterized chromonic system.

  11. Aggregation behavior and chromonic liquid crystal properties of an anionic monoazo dye

    SciTech Connect

    Horowitz, Viva R.; Janowitz, Lauren A.; Modic, Aaron L. [Department of Physics and Astronomy, Swarthmore College, Swarthmore, Pennsylvania 19081 (United States); Heiney, Paul A. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Collings, Peter J. [Department of Physics and Astronomy, Swarthmore College, Swarthmore, Pennsylvania 19081 (United States); Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

    2005-10-01

    X-ray scattering and various optical techniques are utilized to study the aggregation process and chromonic liquid crystal phase of the anionic monoazo dye Sunset Yellow FCF. The x-ray results demonstrate that aggregation involves {pi}-{pi} stacking of the molecules into columns, with the columns undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye concentration. Optical absorption measurements on dilute solutions reveal that the aggregation takes place at all concentrations, with the average aggregation number increasing with concentration. A simple theory based on the law of mass action and an isodesmic aggregation process is in excellent agreement with the experimental data and yields a value for the 'bond' energy between molecules in an aggregate. Measurements of the birefringence and order parameter are also performed as a function of temperature in the chromonic liquid crystal phase. The agreement between these results and a more complicated theory of aggregation is quite reasonable. Overall, these results both confirm that the aggregation process for some dyes is isodesmic and provide a second example of a well-characterized chromonic system.

  12. Aggregation behavior and chromonic liquid crystal properties of an anionic monoazo dye.

    PubMed

    Horowitz, Viva R; Janowitz, Lauren A; Modic, Aaron L; Heiney, Paul A; Collings, Peter J

    2005-10-01

    X-ray scattering and various optical techniques are utilized to study the aggregation process and chromonic liquid crystal phase of the anionic monoazo dye Sunset Yellow FCF. The x-ray results demonstrate that aggregation involves pi-pi stacking of the molecules into columns, with the columns undergoing a phase transition to an orientationally ordered chromonic liquid crystal phase at high dye concentration. Optical absorption measurements on dilute solutions reveal that the aggregation takes place at all concentrations, with the average aggregation number increasing with concentration. A simple theory based on the law of mass action and an isodesmic aggregation process is in excellent agreement with the experimental data and yields a value for the "bond" energy between molecules in an aggregate. Measurements of the birefringence and order parameter are also performed as a function of temperature in the chromonic liquid crystal phase. The agreement between these results and a more complicated theory of aggregation is quite reasonable. Overall, these results both confirm that the aggregation process for some dyes is isodesmic and provide a second example of a well-characterized chromonic system. PMID:16383405

  13. Analytical and preparative chromatographic procedures for obtaining pure cresyl violet and cresyl red from commercial cresyl violet.

    PubMed

    Urrutia, M N; Ortiz, C S

    2015-04-01

    Cresyl violet and cresyl red, components of commercial cresyl violet acetate, were separated and purified using preparative column liquid chromatography. The stationary phase was silica gel and gradient elution was carried out using chloroform:methanol. The purified dyes were obtained in high yield; 51% of the original lot was recovered as cresyl violet and 40% as cresyl red. Separated materials were characterized by nuclear magnetic resonance and mass spectroscopy; UV-visible and Fourier-transform infrared spectra also were obtained for samples of pure cresyl violet and cresyl red. The colored constituents of the commercial dye lot were identified using thin layer chromatography and reverse phase high performance liquid chromatography. Both methodologies were suitable for routine testing; reverse phase high performance liquid chromatography is an appropriate tool for quality control and high resolution identification of these compounds. PMID:25358291

  14. Polymer photonic crystal dye lasers as label free evanescent cell sensors

    NASA Astrophysics Data System (ADS)

    Christiansen, Mads B.; Lopacinska, Joanna M.; Jakobsen, Mogens H.; Mortensen, Niels A.; Dufva, Martin; Kristensen, Anders

    2009-08-01

    Dye doped polymer photonic crystal band edge lasers are applied for evanescent wave sensing of cells. The lasers are rectangular shaped slab waveguides of dye doped polymer on a glass substrate, where a photonic crystal is formed by 100 nm deep air-holes in the surface of the 375 nm high waveguides. The lasers are fabricated by combined nanoimprint and photolithography (CNP) in Ormocore hybrid polymer doped with the laser dye Pyrromethene 597. The lasers emit in the chip plane at a wavelength around 595 nm when pumped with 5 ns pulses from a compact frequency doubled Nd:YAG laser. We investigate the sensitivity of photonic crystal band-edge lasers to partial coverage with HeLa cells. The lasers are chemically activated with a flexible UV activated anthraquinone based linker molecule, which enables selective binding of cells and molecules. When measuring in Phosphate Buffered Saline (PBS), which has a refractive index close to that of the cells, the emission wavelength depends linearly on the cell density on the sensor surface. Our results demonstrate that nanostructured hybrid polymer lasers, which are cheap to fabricate and very simple to operate, can be selectively chemically activated with UV sensitive photolinkers for further bioanalytical applications. This opens the possibility to functionalize arrays of optofluidic laser sensors with different bio-recognition molecules for multiplexed sensing. The linear relationship between cell coverage and wavelength indicates that the slight refractive index perturbation from the partial coverage of the sensor influences the entire optical mode, rather than breaking down the photonic crystal feedback.

  15. Epitaxial growth of two-dimensional cyanine dye single crystals by adsorption at a pre-conditioned fatty acid monolayer

    NASA Astrophysics Data System (ADS)

    Schmitt, Franz-Josef; Knoll, Wolfgang

    1990-01-01

    We have studied the adsorption of water-soluble cyanine dyes (pseudoisocyanine, PIC and "stains all", SA) to monomolecular layers of arachidic acid (AA) at the water-air interface in a Langmuir trough. Upon adsorption the dye molecules organize themselves and form two-dimensional J-aggregates that can easily be observed and characterized in the fluorescence microscope. We show that AA can be "conditioned" by the adsorption of PIC in a lateral order that can be read-out after desorption of this first dye, by the adsorption of another dye, SA in our case. We interpret this memory effect as being caused by a structural and/or orientational modification of the AA monolayer that controls in addition to an electrostatic contribution, details of the crystal morphology and in this sense is a first example of epitaxial growth of two-dimensional organic crystals.

  16. Determination of textile dyes by means of non-aqueous capillary electrophoresis with electrochemical detection

    Microsoft Academic Search

    Alejandra-Alicia Peláez-Cid; Sonia Blasco-Sancho; Frank-Michael Matysik

    2008-01-01

    Eight textile dye compounds including five cationic dyes, namely, basic blue 41, basic blue 9, basic green 4, basic violet 16 and basic violet 3, and three anionic dyes, acid green 25, acid red 1 and acid blue 324, were separated and detected by non-aqueous capillary electrophoresis (NACE) with electrochemical detection. Simultaneous separations of acid and basic dyes were performed

  17. Biodecolorization and biodegradation potential of recalcitrant triphenylmethane dyes by Coriolopsis sp. isolated from compost.

    PubMed

    Chen, Si Hui; Yien Ting, Adeline Su

    2015-03-01

    Triphenylmethane dyes (TPM) are recalcitrant colorants brought into the environment. In this study, a lesser-known white rot fungus Coriolopsis sp. (1c3), isolated from compost of Empty Fruit Bunch (EFB) of oil palm, was explored for its decolorization potential of TPM dyes. The isolate 1c3 demonstrated good decolorization efficiencies in the treatment of Crystal Violet (CV; 100 mg l(-1)), Methyl Violet (MV; 100 mg l(-1)) and Cotton Blue (CB; 50 mg(-1)), with 94%, 97% and 91%, within 7, 7 and 1 day(s), respectively. Malachite Green (MG; 100 mg l(-1)) was the most recalcitrant dye, with 52% decolorization after 9 days. Dye removal by 1c3 was presumably via biosorption, whereby the process was determined to be influenced by fungal biomass, initial dye concentrations and oxygen requirements. Biodegradation was also a likely mechanism responsible for dye removal by 1c3, occurred as indicated by the reduction of dye spectra peaks. Detection of laccase, lignin peroxidase and NADH-DCIP reductase activities further substantiate the possible occurrence of biodegradation of TPM dyes by 1c3. PMID:25527986

  18. Influence of the layer thickness and concentration of dye molecules on the emission amplification in cholesteric liquid crystals

    SciTech Connect

    Alaverdyan, R B; Gevorgyan, A A; Chilingaryan, A D; Chilingaryan, Yu S [Department of Physics, Yerevan State University, Yerevan (Armenia)

    2008-05-31

    The propagation of light through a planar layer of a cholesteric liquid crystal doped with dye molecules is considered. The features of the emission spectra of the crystal are studied both in the absence and presence of dielectric boundaries. The increase in the emission intensity is investigated for different layer thicknesses and different concentrations of dye molecules. It is shown that an anomalously strong increase in the emission intensity with the diffraction intrinsic polarisation takes place in the case of a comparatively small crystal thickness and a relatively low concentration of dye molecules. The obtained results can be used for the development of miniature lasers with the circular polarisation of the fundamental radiation mode. (laser applications and other topics in quantum electronics)

  19. Optical phase conjugation in azo-dye doped chiral liquid crystal

    SciTech Connect

    Karpinski, Pawel; Miniewicz, Andrzej [Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)

    2012-10-15

    We report on optical phase conjugation phenomenon observed in chiral nematic liquid crystal showing band gap type Bragg reflection. The phase conjugate to the signal beam is observable only in the small temperature interval when the Bragg condition is fulfilled and only for circularly polarized light. The optical phase conjugation signals were observed at low cw laser light intensities (<100 mW/cm{sup 2}, {lambda} = 532 nm). Estimated value of third order optical susceptibility {chi}{sup (3)} = 2.8 Multiplication-Sign 10{sup -17} m{sup 2}/V{sup 2} is attributed to enhancement due to photoisomerisation of azo-dye (disperse red 1) inducing molecular reorientation process of liquid crystal molecules.

  20. Color cone lasing emission in a dye-doped cholesteric liquid crystal with a single pitch.

    PubMed

    Lee, C-R; Lin, S-H; Yeh, H-C; Ji, T-D; Lin, K-L; Mo, T-S; Kuo, C-T; Lo, K-Y; Chang, S-H; Fuh, Andy Y-G; Huang, S-Y

    2009-07-20

    This work investigates a novel color cone lasing emission (CCLE) based on a one-dimensional photonic crystal-like dye-doped cholesteric liquid crystal (DDCLC) film with a single pitch. The lasing wavelength in the CCLE is distributed continuously at 676.7-595.6 nm, as measured at a continuously increasing oblique angle relative to the helical axis of 0-50 degrees . This work demonstrates that lasing wavelength coincides exactly with the wavelength at the long wavelength edge of the CLC reflection band at oblique angles of 0-50 degrees . Simulation results of dispersion relations at different oblique angles using Berreman's 4X4 matrix method agrees closely with experimental results. Some unique and important features of the CCLE are identified and discussed. PMID:19654696

  1. Decolorization of synthetic dyes using a copper complex with glucaric acid

    Microsoft Academic Search

    Pradeep Verma; Vishal Shah; Petr Baldrian; Ji??? Gabriel; Pavel Stopka; TomᚠTrnka; František Nerud

    2004-01-01

    Selected azo, acridine, triphenyl methane, anthraquinone and thiazine-based dyes were decolorized using a catalytic system consisting of Cu(II)\\/glucaric acid\\/H2O2. More than 90% decolorization was obtained with 100 ppm Acridine Orange, Azure B, Chicago Sky Blue, Crystal Violet, Methyl Orange, Poly B-411, Reactive Black 5, Reactive Blue 2, and Remazol Brilliant Blue R within 24 h. Seventy to eighty percent decolorization

  2. Measurement of helical twisting power based on axially symmetrical photo-aligned dye-doped liquid crystal film.

    PubMed

    Ko, Shih-Wei; Huang, Shu-Hao; Fuh, Andy Y-G; Lin, Tsung-Hsien

    2009-08-31

    This investigation demonstrates a simple but accurate method for measuring the helical twisting power of chiral doped liquid crystals using axially symmetrical photo-alignment in azo dye-doped liquid crystal films. As reported in our previous paper, a reversed twist effect produces a disclination line in photo-aligned axially symmetrical liquid crystal films. The pitch and helical twisting power can be obtained by measuring the rotation angle of the disclination line in chrial doped liquid crystal. This method is independent of cell gap and provide an error below 0.5%. PMID:19724591

  3. Violet root rot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fungus causing violet root rot, Helicobasidium brebissonii (anamorph Rhizoctonia crocorum), is widely distributed in Europe and North America but is rarely of much economic importance on alfalfa. The disease has also been reported in Australia, Argentina, and Iran. The disease is characterized b...

  4. Band-tunable color cone lasing emission based on a dye-doped cholesteric liquid crystal film

    Microsoft Academic Search

    Chia-Rong Lee; S.-H. Lin; H.-C. Yeh; T.-D. Ji; J.-H. Liu; P.-C. Yang; T.-S. Mo; S.-Y. Huang; C.-T. Kuo; K.-Y. Lo; Andy Y. Fuh

    2010-01-01

    This investigation reports for the first time a novel phenomenon, called band-tunable color cone lasing emission (CCLE), based on a single-pitched one-dimensional photonic crystal-like dye-doped cholesteric liquid crystal (DDCLC) cell. The lasing wavelength in the CCLE pattern is distributed continuously at 676.7-595.6 nm as the oblique angle increases continuously from 0° to 50° relative to the helical axis. The variation

  5. Synthesis, crystal structures and spectroscopic characterizations of two difluoroboradiaza- s-indacene dyes

    NASA Astrophysics Data System (ADS)

    Yu, Yan-Hong; Shen, Zhen; Xu, Hai-Yun; Wang, Yan-Wei; Okujima, Tetsuo; Ono, Noboru; Li, Yi-Zhi; You, Xiao-Zeng

    2007-02-01

    Two new 8-(4-dimethylaminophenyl) substituted boron-dipyrromethene (BDP) dyes: 1,2,6,7-tetraethyl-4,4-difluoro-3,5-dimethyl-8-(4-dimethylaminophenyl)-4-bora-3 a,4 a-diaza- s-indacene (5) and 4,4-difluoro-1,2,3,5,6,7-hexamethyl-8-(4-dimethylaminophenyl)-4-bora-3 a,4 a-diaza- s-indacene (6) have been synthesized and their crystal structures are determined by X-ray diffraction analysis. The torsion angles of 8-phenyl ring and the indacene plane are 79.61° for 5 and 87.56° for 6, respectively. The absorption and steady-state fluorescence properties in different solvents have been investigated. The fluorescence quantum yields of the two dyes are lower in more polar solvents, which can be ascribed to the intramolecular charge transfer from the aniline to the BDP unit. Protonation of the aniline moiety at low pH in MeOH-H 2O (1:1 v/v) solution causes a large fluorescence enhancement. The p Ka values calculated from the pH dependent fluorescence emission spectra are 3.14 for 5 and 3.09 for 6, respectively. They are suitable as pH probes excitable with visible light.

  6. Highly Efficient Plastic Crystal Ionic Conductors for Solid-state Dye-sensitized Solar Cells

    PubMed Central

    Hwang, Daesub; Kim, Dong Young; Jo, Seong Mu; Armel, Vanessa; MacFarlane, Douglas R.; Kim, Dongho; Jang, Sung-Yeon

    2013-01-01

    We have developed highly efficient, ambient temperature, solid-state ionic conductors (SSICs) for dye-sensitized solar cells (DSSCs) by doping a molecular plastic crystal, succinonitrile (SN), with trialkyl-substituted imidazolium iodide salts. High performance SSICs with enhanced ionic conductivity (2–4?mScm?1) were obtained. High performance solid-state DSSCs with power conversion efficiency of 7.8% were fabricated using our SSICs combined with unique hierarchically nanostructured TiO2 sphere (TiO2-SP) photoelectrodes; these electrodes have significant macroporosity, which assists penetration of the solid electrolyte into the electrode. The performance of our solid-state DSSCs is, to the best of our knowledge, the highest reported thus far for cells using plastic crystal-based SSICs, and is comparable to that of the state-of-the-art DSSCs which use ionic liquid type electrolytes. This report provides a logical strategy for the development of efficient plastic crystal-based SSICs for DSSCs and other electrochemical devices. PMID:24343425

  7. Aggregation behavior and chromonic liquid crystal phase of a dye derived from naphthalenecarboxylic acid.

    PubMed

    Tomasik, Michelle R; Collings, Peter J

    2008-08-14

    Polarizing microscopy, X-ray scattering, and absorption spectroscopy are used to investigate the aggregation process and chromonic liquid crystal of the anionic compound Bordeaux dye, a product of the sulfonation of the dibenzimidazole derivative of naphthalenetetracarboxylic acid. Polarizing microscopy reveals that the liquid crystal phase forms at room temperature when the concentration is only about 6 wt%, a value lower than what is found in many aggregating systems. The X-ray results indicate that the aggregation is via columns, with a cross-sectional area about 2.5 times larger than the individual molecule. Absorption spectroscopy shows a significant change in the absorption spectrum due to aggregation, which is nicely explained by a simple theory of isodesmic aggregation and excitonic coupling between the molecules in an aggregate. The "stacking free energy change" for a molecule in an aggregate relative to a molecule in solution is estimated to be about 9 kBT, a larger value than that found in the one other system where it has been estimated. PMID:18646804

  8. 8-Aryl substituted boron-dipyrromethene dyes: crystal structures and computational studies

    NASA Astrophysics Data System (ADS)

    Herradón, Bernardo; Chana, Antonio; Alonso, Mercedes; Amat-Guerri, Francisco; Liras, Marta; Maestro, Miguel A.

    2004-07-01

    The single crystal X-ray diffraction structures of 8-[4-(acetoxymethyl)]phenyl-2,6-diethyl-4,4-difluoro-1,3,5,7-tetramethyl-3a,4a-diaza-4-bora- s-indacene (PAr1Ac, 4) and 8-[4-(3-acetoxypropyl)]phenyl-2,6-diethyl-4,4-difluoro-1,3,5,7-tetramethyl-3a,4a-diaza-4-bora- s-indacene (PAr3Ac, 5) are reported. Although, these two compounds are quite similar, their solid structures are quite unlike, showing remarkable differences in the crystal system, number of molecules in the asymmetric unit, molecular conformation, and supramolecular packing motif. The structures obtained from the X-ray diffraction analysis have been used as starting geometries for quantum chemical calculations (overall energy, HOMO and LUMO, dipole moment, and molecular electrostatic potential). Overall, these results are starting points to understand the photophysical and chemical properties of the so-called 'pyrromethene' dyes.

  9. Photo-tuning of lasing from a dye-doped cholesteric liquid crystals by photoisomerization of a sugar derivative having plural azobenzene groups

    Microsoft Academic Search

    Seiji Kurihara; Yohko Hatae; Teppei Yoshioka; Masaki Moritsugu; Tomonari Ogata; Takamasa Nonaka

    2006-01-01

    Cholesteric liquid crystal (Ch LC) was prepared by mixing a nematic LC, a sugar derivative having plural azobenzene substituents, and a laser dye. Laser emission from the dye-doped Ch LC was observed at the longer edge of the selective reflection band of the Ch LC. Reversible change in the helical pitch of the Ch LC was caused by the trans-cis

  10. Comparison of the performance of photonic band-edge liquid crystal lasers using different dyes as the gain medium

    NASA Astrophysics Data System (ADS)

    Mowatt, Carrie; Morris, Stephen M.; Song, Myoung Hoon; Wilkinson, Timothy D.; Friend, Richard H.; Coles, Harry J.

    2010-02-01

    The primary concern of this work is to study the emission characteristics of a series of chiral nematic liquid crystal lasers doped with different laser dyes (DCM, pyrromethene 580, and pyrromethene 597) at varying concentrations by weight (0.5-2 wt %) when optically pumped at 532 nm. Long-wavelength photonic band-edge laser emission is characterized in terms of threshold energy and slope efficiency. At every dye concentration investigated, the pyrromethene 597-doped lasers exhibit the highest slope efficiency (ranging from 15% to 32%) and the DCM-doped lasers the lowest (ranging from 5% to 13%). Similarly, the threshold was found to be, in general, higher for the DCM-doped laser samples in comparison to the pyrromethene-doped laser samples. These results are then compared with the spectral properties, quantum efficiencies and, where possible, fluorescence lifetimes of the dyes dispersed in a common nematic host. In accordance with the low thresholds and high slope efficiencies, the results show that the molar extinction coefficients and quantum efficiencies are considerably larger for the pyrromethene dyes in comparison to DCM, when dispersed in the liquid crystal host.

  11. 21 CFR 73.3107 - Carbazole violet.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...CERTIFICATION Medical Devices § 73.3107 Carbazole violet. (a) Identity. The color additive is carbazole violet (Pigment Violet 23) (CAS Reg. No. 6358-30-1, Colour Index No. 51319). (b) Uses and restrictions. (1) The...

  12. 21 CFR 73.3107 - Carbazole violet.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...CERTIFICATION Medical Devices § 73.3107 Carbazole violet. (a) Identity. The color additive is carbazole violet (Pigment Violet 23) (CAS Reg. No. 6358-30-1, Colour Index No. 51319). (b) Uses and restrictions. (1) The...

  13. 21 CFR 73.3107 - Carbazole violet.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...CERTIFICATION Medical Devices § 73.3107 Carbazole violet. (a) Identity. The color additive is carbazole violet (Pigment Violet 23) (CAS Reg. No. 6358-30-1, Colour Index No. 51319). (b) Uses and restrictions. (1) The...

  14. Laser dye technology

    SciTech Connect

    Hammond, P R

    1999-09-01

    The author has worked with laser dyes for a number of years. A first interest was in the Navy blue-green program where a flashlamp pumped dye laser was used as an underwater communication and detection device. It made use of the optical window of sea-water--blue for deep ocean, green for coastal water. A major activity however has been with the Atomic Vapor Laser Isotope Separation Program (AVLIS) at the Lawrence Livermore National Laboratory. The aim here has been enriching isotopes for the nuclear fuel cycle. The tunability of the dye laser is utilized to selectively excite one isotope in uranium vapor, and this isotope is collected electrostatically as shown in Figure 1. The interests in the AVLIS program have been in the near ultra-violet, violet, red and deep-red.

  15. Bioadsorption of methyl violet from aqueous solution onto Pu-erh tea powder

    Microsoft Academic Search

    Ping Li; Ya-Juan Su; Yan Wang; Bo Liu; Li-Ming Sun

    2010-01-01

    Chinese unique Pu-erh tea powder (PTP), with leached active ingredients, was used here to adsorb methyl violet (MV), a cationic dye. The effects of several variables on the removal of methyl violet were studied at 25°C, including pH value, contact time, quantity of the adsorbent, initial concentration, and particle size of the adsorbent. The results showed that the particle size

  16. Dye-sensitized nanoarrays with discotic liquid crystals as interlayer for high-efficiency inverted polymer solar cells.

    PubMed

    Shi, Yueqin; Tan, Licheng; Chen, Yiwang

    2014-10-22

    The well-aligned and highly uniform one-dimensional ZnO with organic dyes core/shell (ZNs) and ZnO with dyes and liquid crystals core/double-shells nanoarrays (ZNLs) with controllable lengths were fabricated as electron transport layers (ETLs) in inverted polymer solar cells (PSCs). Ditetrabutylammonium cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato) ruthenium(II) dye (N719) was presented to reduce the surface defects of ZnO nanoarrays (NAs). In addition, the shell modification could decrease the electron injection barrier between ZnO and active layer, thereby facilitating electron injection effectively and forming a direct electron transport channel into the cathode. Due to the orientation of nanoarrays and the self-organization of 3,6,7,10,11-pentakis(hexyloxy)-2-hydroxytriphenylene liquid crystals (LCs) in liquid crystalline mesophase and isotropic phase transition, the components of active layer would be driven rearrange and infiltrate among the interspaces of nanoarrays more orderly. The increased interfacial contact between cathode and active layer would benefit charge generation, transportation and collection. On the basis of these advantages, it was found the N719 shell and N719/LCs double-shells modifications of ZnO NAs could boost the photovoltaic performance of PSCs with the best power conversion efficiency (PCE) of 7.3% and 8.0%, respectively. PMID:25269148

  17. Plant-mediated synthesis of silver-nanocomposite as novel effective azo dye adsorbent

    NASA Astrophysics Data System (ADS)

    Satapathy, Mantosh Kumar; Banerjee, Priya; Das, Papita

    2015-01-01

    Toxicity of textile effluent is a globally alarming issue nowadays. In order to address this problem, a cost-effective and environment-friendly technique for adsorption of toxic dyes has been introduced in this research. Firstly in this study, green synthesis of silver nanoparticles (AgNPs) having antibacterial efficacy, had been carried out using leaf extracts of Azadirachta indica as reducing as well as capping agent. This research idea was further extended for the development and application of a novel method of preparation of silver-nanocomposite using synthesized microwave-assisted AgNPs with soil as a novel nanocomposite to adsorb hazardous dyes. However, this nanocomposite was found to possess higher efficiency and adsorption capacity in comparison to soil as adsorbent for the removal of crystal violet dye under same experimental conditions. Additionally, it was also observed that use of this Ag-nanocomposite as adsorbent helped in achieving about 97.2 % removal of crystal violet dye from the effluent solution.

  18. Final report on the safety assessment of Acid Violet 43.

    PubMed

    Fiume, M Z

    2001-01-01

    Acid Violet 43 is an anthraquinone color that may be used as a colorant in cosmetic formulations that are hair dyes, colors, and coloring rinses. Batches of Acid Violet 43 that are certified to meet the United States Food and Drug Administration (U.S. FDA) specifications are termed Ext. D & C Violet No. 2. Hair dyes and colors containing Acid Violet 43 are considered coal tar ingredients and, as such, routinely bear a caution statement regarding potential skin irritation and instructions for determining whether the product causes skin irritation in any given individual. Expected concentrations of use are less than or equal to 1%. Impurities include anthracenedione derivatives, p-toluidine, and p-toluidine sulfonic acid, as well as heavy metals. Based on extensive safety test data, the U.S. FDA has established specifications (including limits on impurities) for Ext. D & C Violet No. 2 that allow its use in any cosmetic. It is the certified color (Ext. D & C Violet No. 2) that has been evaluated in the following safety tests. Oral toxicity tests do not demonstrate significant acute toxicity. In a short-term dermal toxicity study using guinea pigs and a subchronic dermal toxicity study using rabbits, no signs of systemic toxicity and no significant local skin reactions were noted. This ingredient was not genotoxic in bacterial assays, nor was it carcinogenic when applied to mouse skin at a 1% concentration. Accordingly, Acid Violet 43 was determined to be safe for use in hair dye formulations, when impurities are limited as follows: < or = 18% volatile matter (at 135 degrees C) and chlorides and sulfates (calculated as sodium salts); < or = 0.4% water-insoluble matter; < or = 0.2% 1-hydroxy-9,10-anthracenedione; < or = 0.2% 1,4-dihydroxy-9,10-anthracenedione; < or = 0.1% p-toluidine; < or = 0.2% p-toluidine sulfonic acids, sodium salts; < or = 1% subsidiary colors; < or = 20 ppm lead (as Pb); < or = 3 ppm arsenic (as As); < or = 1 ppm mercury (as Hg); and with > or = 80% total color. PMID:11766130

  19. Polyamide as an efficient sorbent for simultaneous interface-free determination of three Sudan dyes in saffron and urine using high-performance liquid chromatography-ultra violet detection.

    PubMed

    Saeidi, Iman; Barfi, Behruz; Payrovi, Moazameh; Feizy, Javid; Sheibani, Hojat A; Miri, Mina; Ghollasi Moud, Farahnaz

    2015-01-01

    With polyamide (PA) as an efficient sorbent for solid phase extraction (SPE) of Sudan dyes II, III and Red 7B from saffron and urine, their determination by HPLC was performed. The optimum conditions for SPE were achieved using 7 mL methanol/water (1:9, v/v, pH 7) as the washing solvent and 3 mL tetrahydrofuran for elution. Good clean-up and high (above 90%) recoveries were observed for all the analytes. The optimized mobile phase composition for HPLC analysis of these compounds was methanol-water (70:30, v/v). The SPE parameters, such as the maximum loading capacity and breakthrough volume, were also determined for each analyte. The limits of detection (LODs), limits of quantification (LOQs), linear ranges and recoveries for the analytes were 4.6-6.6 microg/L, 13.0-19.8 microg/L, 13.0-5000 microg/L (r2>0.99) and 92.5%-113.4%, respectively. The precisions (RSDs) of the overall analytical procedure, estimated by five replicate measurements for Sudan II, III and Red 7B in saffron and urine samples were 2.3%, 1.8% and 3.6%, respectively. The developed method is simple and successful in the application to the determination of Sudan dyes in saffron and urine samples with HPLC coupled with UV detection. PMID:25958664

  20. Plasma-Assisted Synthesis of High-Mobility Atomically Layered Violet Phosphorus.

    PubMed

    Tsai, Hsu-Sheng; Lai, Chih-Chung; Hsiao, Ching-Hung; Medina, Henry; Su, Teng-Yu; Ouyang, Hao; Chen, Tai-Hsiang; Liang, Jenq-Horng; Chueh, Yu-Lun

    2015-07-01

    Two-dimensional layered materials such as graphene, transition metal dichalcogenides, and black phosphorus have demonstrated outstanding properties due to electron confinement as the thickness is reduced to atomic scale. Among the phosphorus allotropes, black phosphorus, and violet phosphorus possess layer structure with the potential to be scaled down to atomically thin film. For the first time, the plasma-assisted synthesis of atomically layered violet phosphorus has been achieved. Material characterization supports the formation of violet phosphorus/InN over InP substrate where the layer structure of violet phosphorus is clearly observed. The identification of the crystal structure and lattice constant ratifies the formation of violet phosphorus indeed. The critical concept of this synthesis method is the selective reaction induced by different variations of Gibbs free energy (?G) of reactions. Besides, the Hall mobility of the violet phosphorus on the InP substrate greatly increases over the theoretical values of InP bulk material without much reduction in the carrier concentration, suggesting that the mobility enhancement results from the violet phosphorus layers. Furthermore, this study demonstrates a low-cost technique with high compatibility to synthesize the high-mobility atomically layered violet phosphorus and open the space for the study of the fundamental properties of this intriguing material as a new member of the fast growing family of 2D crystals. PMID:26070035

  1. Adsorption and kinetic studies of seven different organic dyes onto magnetite nanoparticles loaded tea waste and removal of them from wastewater samples

    NASA Astrophysics Data System (ADS)

    Madrakian, Tayyebeh; Afkhami, Abbas; Ahmadi, Mazaher

    2012-12-01

    Adsorption of seven different organic dyes from aqueous solutions onto magnetite nanoparticles loaded tea waste (MNLTW) was studied. MNLTW was prepared via a simple method and was fully characterized. The properties of this magnetic adsorbent were characterized by scanning electron microscopy and X-ray diffraction. Adsorption characteristics of the MNLTW adsorbent was examined using Janus green, methylene blue, thionine, crystal violet, Congo red, neutral red and reactive blue 19 as adsorbates. Dyes adsorption process was thoroughly studied from both kinetic and equilibrium points of view for all adsorbents. The experimental isotherm data were analyzed using Langmuir, Freundlich, Sips, Redlich-Peterson, Brouers-Sotolongo and Temkin isotherms. The results from Langmuir isotherm indicated that the capacity of MNLTW for the adsorption of cationic dyes was higher than that for anionic dyes. The adsorption kinetics was tested for the pseudo-first order and pseudo-second order kinetic models at different experimental conditions.

  2. Fluorescence screening of leucomalachite green and leucogentian violet residues in catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tripheylmethane dyes malachite green (MG) and gentian violet (GV) are effective fungicides, ectoparasiticides and disinfectants in aquaculture. This practice may leave toxic residues in seafood which is not allowed by FDA and many regulatory agencies worldwide. In this work, residues of their me...

  3. Conservation Assessment for Great-spurred Violet

    E-print Network

    Tech University. #12;EXECUTIVE SUMMARY Great-spurred violet (Viola selkirkii Pursh ex Goldie; Violaceae-spurred violet, Viola selkirkii, Black Hills, boreal forest, myrmecochory. ACKNOWLEDGMENTS Many individuals have

  4. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Identity. The color additive manganese violet is a violet pigment obtained by reacting phosphoric acid, ammonium dihydrogen...and manganese dioxide at temperatures above 450 °F. The pigment is a manganese ammonium pyrophosphate complex having the...

  5. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Identity. The color additive manganese violet is a violet pigment obtained by reacting phosphoric acid, ammonium dihydrogen...and manganese dioxide at temperatures above 450 °F. The pigment is a manganese ammonium pyrophosphate complex having the...

  6. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Identity. The color additive manganese violet is a violet pigment obtained by reacting phosphoric acid, ammonium dihydrogen...and manganese dioxide at temperatures above 450 °F. The pigment is a manganese ammonium pyrophosphate complex having the...

  7. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Identity. The color additive manganese violet is a violet pigment obtained by reacting phosphoric acid, ammonium dihydrogen...and manganese dioxide at temperatures above 450 °F. The pigment is a manganese ammonium pyrophosphate complex having the...

  8. 21 CFR 73.2775 - Manganese violet.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Identity. The color additive manganese violet is a violet pigment obtained by reacting phosphoric acid, ammonium dihydrogen...and manganese dioxide at temperatures above 450 °F. The pigment is a manganese ammonium pyrophosphate complex having the...

  9. Modification of the Radiation of a Luminescent dye embedded in a finite one-dimensional Photonic Crystal

    E-print Network

    Manzanares-Martinez, J

    2010-01-01

    A numerical modeling of the radiation emitted from a Luminescent dye embedded in a finite one-dimensional photonic crystal is presented. The Photonic Band Structure and the Photonic Density of States are derived using classical electromagnetic approach, and the Finite Difference Time-Domain formalism is used to calculate the electromagnetic field distribution. It is found that the periodic modulation provides an effective way to control the Spontaneous Emission under certain circumstances. We find the conditions where a large amount of light can be enhanced on the vicinity of a photonic band edge due to the presence of a high density of states. This phenomena opens the possibility to design new Lasers sources.

  10. Quasi-photonic crystal effect of TiCl?/electrolyte matrix in unipolar dye-absorber devices.

    PubMed

    Park, Dong-Won; Jeong, Yonkil; PremKumar, Thangapandi; Lee, Jaeyoung

    2014-08-27

    Effectiveness of TiCl3 pre- and post-treatments on dye-sensitized solar cells (DSCs) and interfacial charge-transfer properties were investigated. It was confirmed that a yield of current collection was strongly dependent on the position of the TiCl3/electrolyte matrix in the DSC configuration. The interfacial charge-transfer properties were studied using thermionic emission-diffusion process and electrochemical impedance spectroscopy analysis. The TiCl3/electrolyte matrix was considered to be a three-dimensional quasi-photonic crystal with a photonic band gap, which reinforces electric field and facilitates current collection from the TiCl3/electrolyte matrix to the FTO by accelerating electron motion, whereas the potential barrier blocks current collection from the TiO2 bulk region to the FTO and decreases current. PMID:25073121

  11. Dyes in Liquid Crystals: Experimental and Computational Studies of a Guest-Host System Based on a Combined DFT and MD Approach.

    PubMed

    Sims, Mark T; Abbott, Laurence C; Cowling, Stephen J; Goodby, John W; Moore, John N

    2015-07-01

    Practical applications of guest-host liquid crystal systems are critically dependent on the alignment of the guest species within the liquid crystal host. UV/Vis absorption spectroscopy shows that the 1,5-dihydroxy-2,6-bis-(4-propylphenyl)-9,10-anthraquinone dye aligns within the E7 nematic host, giving an experimental dichroic ratio of 9.40 and dye order parameter of 0.74. This alignment was modelled by using a combination of density functional theory (DFT) and molecular dynamics (MD) computational approaches that do not require the input of experimental data. Time-dependent DFT calculations show that the electronic transition dipole moment is highly aligned with the long molecular axis of the dye. Fully atomistic MD simulations show that the long axis of the dye is less highly aligned within the E7 host, indicating that this contribution limits the overall dye alignment and, thereby, the potential practical applications of this particular system. Importantly, this study demonstrates an experimental and combined DFT and MD computational approach that may be applied generally to guest-host systems, providing a potential route to their rational design. PMID:26031244

  12. Decolourisation of industrial dyes by solid-state cultures of Pleurotus pulmonarius

    Microsoft Academic Search

    Giovana Kirst Tychanowicz; Adriana Zilly; Cristina Giatti Marques de Souza; Rosane Marina Peralta

    2004-01-01

    A solid-state system to obtain rapid in vivo industrial dye decolourisation by the white-rot fungus Pleurotus pulmonarius is proposed. When cultivated on glucose\\\\ammonium tartrate–corncob solid-state medium, P. pulmonarius decolourised structurally different synthetic dyes (including azo, triphenylmethane, heterocyclic and polymeric dyes). Amido black, congo red, trypan blue, methyl green, remazol brilliant blue R (RBB), methyl violet, ethyl violet and brilliant cresyl

  13. All-optical modulation in dye-doped nematic liquid crystal photonic bandgap fibers

    Microsoft Academic Search

    Thomas Tanggaard Alkeskjold; Jesper Lægsgaard; Anders Bjarklev; David Sparre Hermann; Anawati Anawati; Jes Broeng; Jun Li; Shin-Tson Wu

    2004-01-01

    Photonic crystal fibers (PCFs) have attracted significant attention during the last years and much research has been devoted to develop fiber designs for various applications, hereunder tunable fiber devices. Recently, thermally and electrically tunable PCF devices based on liquid crystals (LCs) have been demonstrated. However, optical tuning of the LC PCF has until now not been demonstrated. Here we demonstrate

  14. Photo-tuning of lasing from a dye-doped cholesteric liquid crystals by photoisomerization of a sugar derivative having plural azobenzene groups

    NASA Astrophysics Data System (ADS)

    Kurihara, Seiji; Hatae, Yohko; Yoshioka, Teppei; Moritsugu, Masaki; Ogata, Tomonari; Nonaka, Takamasa

    2006-03-01

    Cholesteric liquid crystal (Ch LC) was prepared by mixing a nematic LC, a sugar derivative having plural azobenzene substituents, and a laser dye. Laser emission from the dye-doped Ch LC was observed at the longer edge of the selective reflection band of the Ch LC. Reversible change in the helical pitch of the Ch LC was caused by the trans-cis photoisomerization of the sugar derivative having plural azobenzene substituents. According to the change in the helical pitch of the Ch LC, the lasing properties were simultaneously affected by the UV and visible light irradiation; laser emission wavelength, intensity, singlemode-multimode.

  15. High viscous light-scattering crystal growth inhibitors for solid-state dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Cong, Shan; Yi, Qinghua; Wang, Yun; Zhao, Jie; Sun, Yinghui; Zou, Guifu

    2015-04-01

    A kind of high viscous light-scattering crystal growth inhibitors (LCGIs) are synthesized and characterized in details. The thermal, electrical and light-scattering properties of LCGIs-based solid-state electrolytes are also investigated. Addition of the high viscous LCGI to ionic crystal EMII could effectively prevent EMII from recrystallization and enhance the light-harvesting efficiency of the TiO2 photoanode, and thus larger photocurrent is obtained. The resulting solid-state dye-sensitized solar cell (ssDSSC) shows a high power conversion efficiency ?5.13% under simulated AM 1.5 solar spectrum irradiation at 100 mW cm-2, and displays better long-term stability than that of referenced low viscous EMIBF4-based electrolyte. More importantly, LCGIs-based electrolytes, acting as conventional TiO2 light-scattering layers, without sacrificing device performances, provide us a feasible method to explore new solid-state electrolytes and much thinner ssDSSCs.

  16. [Toxicogenetic effects of azo- and arylmethane dyes].

    PubMed

    Zimina, T A; Pavlenko, V V

    1990-12-01

    The haploid strain 15B-II4 of Saccharomyces cerevisiae was used to study in an acute experiment the toxic and mutagenic effects of arylmethane dyes Victory Blue (C.I. 44040), Methyl Violet (C.I. 42535), Brilliant Green (C.I. 42040) and cancerogenic aminoazo dye Chrysoidine (C.I. 11270). High biological activity of all the dyes tested was found, based on such toxic effects as cell killing and growth inhibition. Also, it was shown that the dyes could increase the frequency of appearance of nuclear point mutations and cytoplasmic mutations of respiratory deficiency. PMID:2086349

  17. Modulated Laser Action from Dye Containing Holographic Polymer Dispersed Liquid Crystals

    NASA Astrophysics Data System (ADS)

    Jakubiak, Rachel; Brown, Dean; Urbas, Augustine; Tondigia, Vincent; Natarajan, Lalgudi; Sutherland, Richard; Vaia, Richard; Bunning, Timothy

    2004-03-01

    Holographic polymerization of liquid crystal containing photopolymerizable resins enables one-step, rapid formation of multi-phase structures that exhibit partial photonic band gaps. Holographic polymer dispersed liquid crystals (H-PDLCs) provide a versatile platform for diffractive optical elements because the structures are not limited by multi-phase equilibrium but are controlled by the interference of multiple lasers at discrete angles. By incorporating optically active components (coumarin, pyrromethene, quantum dots) into acrylate polymer and nematic liquid crystal H-PDLCs we create optically pumped distributed feedback lasers. The lattice structure of the H-PDLC determines the wavelength, number and propagation direction of laser action from the embedded chromophores. Unlike one-dimensional Bragg stacks made from H-PDLCs where just one propagation direction exists, higher dimensional structures generate multiple laser beams creating electric field modulated laser arrays.

  18. Light-controlled electric Freedericksz threshold in dye doped liquid crystals

    SciTech Connect

    Lucchetti, L.; Catani, L.; Simoni, F. [Dipartimento di Scienze e Ingegneria della Materia, dell'Ambiente ed Urbanistica and CNISM Università Politecnica delle Marche, Ancona (Italy)

    2014-05-28

    We report the results of measurements of the threshold of Freedericksz transition in a nematic liquid crystal doped by Methyl-red. We show that in case of dc field the threshold voltage can decrease or increase depending on the light dose, due to the light-induced desorption and adsorption of charge complexes from and on the irradiated surface, that has been recently demonstrated. This effect has the potential to be exploited in optical devices such as liquid crystal microlenses and spatial light modulators.

  19. Optical properties and dye adsorption characteristics of acicular crystal assembled TiO 2 thin films

    Microsoft Academic Search

    Yoshitake Masuda; Kazumi Kato

    2009-01-01

    Fluorine doped tin oxide (FTO) substrates were modified with acicular crystal assembled TiO2 thin films. The thin films increased transparency and decreased reflectance of the substrates. The films had high transparency over 80% in the range from 400 to 850nm. They were about 8% higher than those of bare FTO substrates. The films had low reflectance of about 11% in

  20. Microgap ultra-violet detector

    DOEpatents

    Wuest, C.R.; Bionta, R.M.

    1994-09-20

    A microgap ultra-violet detector of photons with wavelengths less than 400 run (4,000 Angstroms) which comprises an anode and a cathode separated by a gas-filled gap and having an electric field placed across the gap is disclosed. Either the anode or the cathode is semi-transparent to UV light. Upon a UV photon striking the cathode an electron is expelled and accelerated across the gap by the electric field causing interactions with other electrons to create an electron avalanche which contacts the anode. The electron avalanche is detected and converted to an output pulse. 2 figs.

  1. Results from the IMP-J violet solar cell experiment and violet cell balloon flights

    NASA Technical Reports Server (NTRS)

    Gaddy, E. M.

    1976-01-01

    The Interplanetary Monitoring Platform-J violet solar cell experiment was flown in an orbit with mild thermal cycling and low hard-particle radiation. The results of the experiment show that violet cells degrade at about the same rate as conventional cells in such an orbit. Balloon flight measurements show that violet solar cells produce approximately 20% more power than conventional cells.

  2. Pulsed electric linear dichroism of triphenylmethane dyes adsorbed on montmorillonite K10 in aqueous media

    SciTech Connect

    Yamaoka, Kiwamu; Sasai, Ryo

    2000-05-01

    Electric linear dichroism (ELD) spectra of two cationic triphenylmethane dyes, crystal violet (CV) and malachite green (MG), bound to sodium montmorillonite K10 (MK-10) were studied at 20 C in aqueous media at two mixing ratios, D/S, of 0.10 and 0.24 in the 700- to 400 nm wavelength region and in the applied electric field strength range between 0 and 3 kV/cm. The specific parallel and perpendicular dichroism ({Delta}A{sub {parallel}}/A and {Delta}A{sub {perpendicular}}/A) spectra of dye-adsorbed MK-10 suspension were measured at a fixed field strength with an apparatus equipped with a 512-channel photodiode array detector. By changing the field strength over a wide range, a series of the reduced dichroism values of the bound dyes were measured at a fixed wavelength. By fitting these dichroism values to theoretical orientation functions, the intrinsic reduced dichroism ({Delta}A/A){sub int} spectra at the limiting high fields (ELD spectrum) were determined for CV and MG bound to MK-10. No appreciable difference was observed at the two D/S values. The ELD spectra of these bound dyes are undulatory but never constant, throughout their absorption region; thus, the dye plane does not lie flatly either on the surface or between layers of MK-10 particle.

  3. Performance evolution of color cone lasing emissions in dye-doped cholesteric liquid crystals at different fabrication conditions.

    PubMed

    Lee, Chia-Rong; Lin, Jia-De; Mo, Ting-Shan; Horng, Chi-Ting; Sun, Han-Ying; Huang, Shuan-Yu

    2015-04-20

    This work investigates the performance evolution of color cone lasing emissions (CCLEs) based on dye-doped cholesteric liquid crystal (DDCLC) cells at different fabrication conditions. Experimental results show that the energy threshold (Eth) and relative slope efficiency (?s) of the lasing signal emitted at each cone angle (0°-35°) in the CCLE decreases and increases, respectively, when the waiting time in a homogenously rubbed aligned DDCLC cell is increased from 0 hr to 216 hr (9 days). This result occurs because defect lines gradually shrink with the anchoring of the surface alignment when the waiting time is increased. Hence, the scattering loss decreases, and the dwelling time of the fluorescence photons in the resonator increases, which in turn enhances the CCLE performance. With the aligned cell given the pretreatment of a rapid annealing processing (RAP), the waiting time for obtaining an optimum CCLE can markedly be reduced sixfold. The surface alignment of the DDCLC cell also plays a necessary role in generating the CCLE. This work provides an insight into the temporal evolution of the performance for the CCLE laser and offers a method (RAP) of significantly speeding up the formation of a CCLE laser with optimum performance. PMID:25969059

  4. Adsorption of dyes from aqueous solutions on activated charcoal

    Microsoft Academic Search

    Muhammad J. Iqbal; Muhammad N. Ashiq

    2007-01-01

    Adsorption of industrially important dyes namely bromophenol blue, alizarine red-S, methyl blue, methylene blue, eriochrome black-T, malachite green, phenol red and methyl violet from aqueous media on activated charcoal has been investigated. The effect of shaking time, pH and temperature on the adsorption behaviour of these dyes has been studied. It was noted that adsorption of all the dyes on

  5. Distributed feedback lasing from electrically tunable dye-doped polymer–liquid crystal transmission gratings

    NASA Astrophysics Data System (ADS)

    Sakhno, O. V.; Gritsai, Y.; Stumpe, J.

    2014-11-01

    In the present work we report low-threshold distributed feedback (DFB) lasing from electrically tunable holographic polymer–liquid crystal transmission gratings of POLIPHEM type doped with pyrromethene 567. Due to their uniform droplet-free micro-morphology, the POLIPHEM gratings possess high diffraction efficiency and excellent optical quality. Second-order lasing with a threshold of ~0.8?µJ/pulse and a bandwidth of ~1?nm was achieved under the excitation of a frequency-doubled Nd:YAG laser operating at 532?nm. The laser emission wavelength was tuned from 572–625?nm by varying the grating period. Application of an electric field switches off or tunes the lasing intensity. An electrically-induced blue-shift of the output laser emission was observed.

  6. Toxicity of imine-iminium dyes and pigments: electron transfer, radicals, oxidative stress and other physiological effects.

    PubMed

    Kovacic, Peter; Somanathan, Ratnasamy

    2014-08-01

    Although conjugation is well known as an important contributor to color, there is scant recognition concerning involvement of imine and iminium functions in the physiological effects of this class of dyes and pigments. The group includes the dyes methylene blue, rhodamine, malachite green, fuchsin, crystal violet, auramine and cyanins, in addition to the pigments consisting of pyocyanine, phthalocyanine and pheophytin. The physiological effects consist of both toxicity and beneficial aspects. The unifying theme of electron transfer-reactive oxygen species-oxidative stress is used as the rationale in both cases. Toxicity is frequently prevented or alleviated by antioxidants. The apparent dichotomy of methylene blue action as both oxidant and antioxidant is rationalized based on similar previous cases. This mechanistic approach may have practical benefit. This review is important in conveying, for the first time, a unifying mechanism for toxicity based on electron transfer-reactive oxygen species-oxidative stress arising from imine-iminium. PMID:24852913

  7. Hydrogen production and metal-dye bioremoval by a Nostoc linckia strain isolated from textile mill oxidation pond.

    PubMed

    Mona, Sharma; Kaushik, Anubha; Kaushik, C P

    2011-02-01

    Biohydrogen production by Nostoc linckia HA-46, isolated from a textile-industry oxidation-pond was studied by varying light/dark period, pH, temperature and ratio of carbon-dioxide and argon in the gas-mixture. Hydrogen production rates were maximum under 18 h of light and 6 h of darkness, pH 8.0, 31°C, a CO(2):Ar ratio 2:10. Hydrogen production of the strain acclimatized to 20 mg/L of chromium/cobalt and 100 mg/L of Reactive red 198/crystal violet dye studied in N-supplemented/deficient medium was 6-10% higher in the presence of 1.5 g/L of NaNO(3). Rates of hydrogen production in the presence of dyes/metals by the strain (93-105 ?mol/h/mg Chlorophyll) were significantly higher than in medium without metals/dyes serving as control (91.3 ?mol/h/mg Chlorophyll). About 58-60% of the two metals and 35-73% of dyes were removed by cyanobacterium. Optimal conditions of temperature, pH and metals/dyes concentration for achieving high hydrogen production and wastewater treatment were found practically applicable as similar conditions are found in the effluent of regional textile-mills. PMID:21109423

  8. Ultra violet disinfection: A 3-year history

    SciTech Connect

    Tubesing, R.R.; Lindeke, D.R.

    1998-07-01

    The Stillwater Wastewater Treatment Facility is one of nine wastewater treatment facilities operated by the Metropolitan Council Environmental Services in the Minneapolis-St. Paul Metropolitan Area. The facility services the cities of Stillwater, Oak Park Heights, and Bayport. In 1993, an ultra violet disinfection facility began operation to provide the disinfection for the Facility. This presentation discusses the reasons for using ultra violet disinfection in lieu of chlorination/dechlorination facilities, the operating performance, and operating cost factors.

  9. Improving the decolorization for textile dyes of a metagenome-derived alkaline laccase by directed evolution.

    PubMed

    Liu, Yu Huan; Ye, Mao; Lu, Yi; Zhang, Xia; Li, Gang

    2011-08-01

    To obtain better performing laccases for textile dyes decolorization, random mutagenesis of Lac591, a metagenome-derived alkaline laccase, was carried out. After three rounds of error-prone PCR and high-throughput screening by assaying enzymatic activity toward the phenolic substrate 2,6-dimethoxyphenol (2,6-DMP), a mutant (Lac3T93) with remarkably improved enzymatic activity was obtained. Sequence analysis revealed that four amino acid substitutions (N40S, V55A, F62L, and E316V) were accumulated in the Lac3T93. Compared to the wild-type enzyme, the specific activity of Lac3T93 toward 2,6-DMP was increased to 4.8-fold (61.22 U/mg), and its optimal temperature and pH were changed to 60°C and 8.0 from 55°C and 7.5 of the wild-type enzyme, respectively. Furthermore, the degradation ability of Lac3T93 for textile dyes was investigated, and the new variant represented improved decolorization percentage for four industrial dyes with complex phenyl structure (Basic Blue 3, Methylene Blue, Bromophenol Blue, and Crystal Violet) and higher decolorization efficiency for Indigo Carmine than that of the parent enzyme. Furthermore, the decolorization percentage of Lac3T93 for five dyes in the absence of hydroxybenzotrizole (HBT) is clearly higher than those of the wild-type enzyme with 1 mM HBT, and HBT can further improve its decolorization ability. PMID:21523474

  10. Fast wavelength-tunable ultra-violet laser source for confocal Fura-2AM imaging

    NASA Astrophysics Data System (ADS)

    Esposito, E.; Harris, J.; McConnell, G.

    2007-02-01

    We report a novel wavelength-flexible laser source for three-dimensional ultra-violet imaging. Based on supercontinuum generation in photonic crystal fiber, the resultant broadband laser source extended from ? = 331 nm into the visible region of the spectrum. Using an electronically-controlled filter wheel and filter set with a response time of approximately 50 ms, rapid wavelength selection was performed. The described scheme is capable of exciting the current range of ultra-violet-excited fluorophores and the simple and rapid wavelength control also provides a new approach for fast ratiometric imaging of Fura-2AM, facilitating an easy method of performing quantitative intracellular calcium concentration measurements.

  11. Origin and evolution of a peraluminous silicic ignimbrite suite: The Violet Town Volcanics

    Microsoft Academic Search

    John D. Clemens; Victor J. Wall

    1984-01-01

    The Violet Town Volcanics are a 373 Ma old, comagmatic, S-type volcanic sequence mainly comprising crystal-rich intracaldera ignimbrites. Rock types vary from rhyolites to rhyodacites, all containing magmatic cordierite and garnet phenocrysts. Variation in the suite is primarily due to fractionation of early-crystallized quartz, plagioclase and biotite (plus minor accessory phases) in a high-level magma chamber prior to eruption. Early

  12. Decolorization of synthetic dyes by solid state cultures of Lentinula ( Lentinus) edodes producing manganese peroxidase as the main ligninolytic enzyme

    Microsoft Academic Search

    Cinthia Gandolfi Boer; Larissa Obici; Cristina Giatti Marques de Souza; Rosane M. Peralta

    2004-01-01

    The ability of the white-rot fungus Lentinula (Lentinus) edodes to decolorize several synthetic dyes was investigated using solid state cultures with corn cob as substrate. Cultures, containing amido black, congo red, trypan blue, methyl green, remazol brilliant blue R, methyl violet, ethyl violet and Poly R478 at 200 ppm, were completely decolorized after 18 days of incubation. Partial decolorization was

  13. Geopolymeric adsorbents from fly ash for dye removal from aqueous solution

    SciTech Connect

    Li, L.; Wang, S.B.; Zhu, Z.H. [Curtin University of Technology, Perth, WA (Australia). Dept. of Chemical Engineering

    2006-08-01

    Adsorbents from coal fly ash treated by a solid-state fusion method using NaOH were prepared. It was found that amorphous aluminosilicate, geopolymers would be formed. These fly ash-derived inorganic polymers were assessed as potential adsorbents for removal of some basic dyes, methylene blue and crystal violet, from aqueous solution. It was found that the adsorption capacity of the synthesised adsorbents depends on the preparation conditions such as NaOH:fly-ash ratio and fusion temperature with the optimal conditions being at 1.2:1 weight ratio of Na:fly-ash at 250-350{sup o}C. The synthesised materials exhibit much higher adsorption capacity than fly ash itself and natural zeolite. The adsorption isotherm can be fitted by Langmuir and Freundlich models while the two-site Langmuir model produced the best results. It was also found that the fly ash derived geopolymeric adsorbents show higher adsorption capacity for crystal violet than methylene blue and the adsorption temperature influences the adsorption capacity. Kinetic studies show that the adsorption process follows the pseudo second-order kinetics.

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

    PubMed

    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 8g/100mL. 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. PMID:25875031

  15. Potential use of low-cost lignocellulosic waste for the removal of direct violet 51 from aqueous solution: equilibrium and breakthrough studies.

    PubMed

    Sadaf, Sana; Bhatti, Haq Nawaz; Nausheen, Sana; Noreen, Saima

    2014-05-01

    An efficient biosorbent, sugarcane bagasse was used in native, HCl-treated, and Na-alginate immobilized form for the removal of Direct Violet 51 dye from aqueous solutions. Batch study was performed to optimize important process parameters, such as pH, contact time, biosorbent dose, initial dye concentration, and temperature. Removal of Direct Violet 51 was found to be favorable at pH 2 with the biosorbent dose of 0.05 g. Biosorption process was found to be exothermic in nature. Maximum dye biosorption (39.6 mg/g) was achieved by using HCl-treated biomass. The pseudo-second-order kinetic and Langmuir adsorption isotherm models showed best fitness to the experimental data. Thermodynamic study was also performed to determine the feasibility of biosorption process. Continuous mode study was performed to optimize the important process parameters, such as bed height, flow rate, and initial dye concentration for maximum removal of Direct Violet 51 dye. The higher bed height, low flow rate, and high initial dye concentration were found to be the better conditions for maximum dye biosorption (17.28 mg/g). The linearized form of the Thomas model equation fitted well to the experimental data. The bed depth service time model was used to express the effect of bed height on breakthrough curves. Characterization of biosorbent was performed by scanning electron microscopy and Fourier transform infrared (FT-IR) analysis. The FT-IR spectral analyses showed the involvement of hydroxyl, carbonyl, and carboxyl groups in biosorption process. These results indicated that sugarcane bagasse biomass could be used as a novel biosorbent for the removal of Direct Violet 51 dye from real textile and related industries. PMID:24468968

  16. Nearly unpolarized and linearly polarized laser generation from dye-doped cholesteric liquid crystal laser using a mirror reflector

    E-print Network

    Wu, Shin-Tson

    propagate through, known as the photonic band gap. Regarded as one-dimensional photonic crystal, CLC crystal laser using a mirror reflector Ying Zhou, Yuhua Huang, and Shin-Tson Wu College of Optics-doped cholesteric liquid crystal (CLC) laser generates circularly polarized laser light in the same handedness

  17. Adsorption behaviors of acid and basic dyes on crosslinked amphoteric starch

    Microsoft Academic Search

    Shimei Xu; Jingli Wang; Ronglan Wu; Jide Wang; Hong Li

    2006-01-01

    Crosslinked amphoteric starch with carboxymethyl and quaternary ammonium groups is investigated as an adsorbent for removal of both acid and basic dyes in solution. Acid Light Yellow 2G, Acid Red G, Methyl Green and Methyl Violet were used to study the adsorption behaviors under various parameters such as pH, dose of amphoteric starches, initial dye concentration, adsorption time and adsorption

  18. Bioadsorption of methyl violet from aqueous solution onto Pu-erh tea powder.

    PubMed

    Li, Ping; Su, Ya-Juan; Wang, Yan; Liu, Bo; Sun, Li-Ming

    2010-07-15

    Chinese unique Pu-erh tea powder (PTP), with leached active ingredients, was used here to adsorb methyl violet (MV), a cationic dye. The effects of several variables on the removal of methyl violet were studied at 25 degrees C, including pH value, contact time, quantity of the adsorbent, initial concentration, and particle size of the adsorbent. The results showed that the particle size of the adsorbent significantly affected the adsorption process, and the nano-sized PTP particles had the best adsorption efficiency. The equilibrium data was analyzed using Langmuir, Freundlich, and Tempkin isotherms models. The pseudo-second-order kinetics model best explained the MV adsorption by PTP of any particle size. The intra-particle diffusion model was also used to analyze the adsorption process, and it was found that smaller adsorbent particles had a bigger boundary layer effect. PMID:20303659

  19. Resonant Rayleigh scattering for the determination of trace amounts of mercury (II) with thiocyanate and basic triphenylmethane dyes

    SciTech Connect

    Liu, S.; Liu, Z.; Zhou, G. [Southwest Normal Univ., Chongqing (China). Inst. of Environmental Chemistry

    1998-05-01

    Intense resonance Rayleigh scattering (RRS) appears when mercury (II) reacts with thiocyanate and a basic triphenylmethane dye (BTPMD), such as crystal violet (CV), ethyl violet (EV), brilliant green (BG), malachite green (MG) or indine green (IG), to form an ion-association complex of the type (BTPMD){sub 2}[Hg(SCN){sub 4}]. The characteristics of RRS spectra of the ion-association complexes and suitable conditions for the reactions were investigated. The intensity of RRS is directly proportional to the concentration of mercury (II) in the range of 0--2.0 {micro}g/25 ml. The RRS methods have very high sensitivities for determination of mercury (II); their detection limits are between 1.68 ng/ml and 6.00 ng/ml on different dye systems. The effects of foreign ions and ways to improve the selectivity were studied. The new highly sensitive methods for the determination of trace amounts of mercury based on the RRS of the ion-association complexes have been developed.

  20. A hybrid laser system consisting of a frequency-doubled, narrow-line-width, distributed-feedback dye laser oscillator and a high saturation-fluence Ce:LiCaAlF6 crystal amplifier

    NASA Astrophysics Data System (ADS)

    Hoa, D. Q.; Hung, N. D.; Moroe, J.; Takeyasu, N.; Imasaka, T.

    2003-05-01

    A tunable narrow-band picosecond dye laser emitting in the ultraviolet region was amplified using a Ce:LiCaAlF6 crystal pumped by the fourth-harmonic emission of a Nd:Y3Al5O12 laser. The single-pass gain obtained exceeded 2 in the spectral range of 288 to 297 nm.

  1. A strategy to reduce the angular dependence of a dye-sensitized solar cell by coupling to a TiO2 nanotube photonic crystal

    NASA Astrophysics Data System (ADS)

    Guo, Min; Xie, Keyu; Liu, Xiaolin; Wang, Yu; Zhou, Limin; Huang, Haitao

    2014-10-01

    Almost all types of solar cells suffer from a decreased power output when the incident light is tilted away from normal since the incident intensity generally follows a cosine law of the incident angle. Making use of the blue shift nature of the Bragg position of a TiO2 nanotube photonic crystal (NT PC) under oblique incidence, we demonstrate experimentally that the use of the NT PC can partially compensate the cosine power loss of a dye-sensitized solar cell (DSSC). The strategy used here is to purposely choose the Bragg position of the NT PC to be at the longer wavelength side of the dye absorption peak. When the incident light is tilted, the blue shift of the Bragg position results in more overlap with the dye absorption peak, generating a higher efficiency that partially compensates the reduced photon flux due to light inclination. Moreover, the unique structure of the vertically aligned TiO2 nanotubes contributes an additional scattering effect when the incident light is tilted. As a result, the power output of a DSSC coupled with the NT PC layer shows a much flatter angular dependence than a DSSC without the NT PC. At all the incident angles, the DSSC coupled with the NT PC layer also shows a higher power conversion efficiency than the one without. The concept of using NT PC to mitigate the angular dependence of DSSCs can be easily extended to many other optoelectronic devices that are irradiance sensitive.Almost all types of solar cells suffer from a decreased power output when the incident light is tilted away from normal since the incident intensity generally follows a cosine law of the incident angle. Making use of the blue shift nature of the Bragg position of a TiO2 nanotube photonic crystal (NT PC) under oblique incidence, we demonstrate experimentally that the use of the NT PC can partially compensate the cosine power loss of a dye-sensitized solar cell (DSSC). The strategy used here is to purposely choose the Bragg position of the NT PC to be at the longer wavelength side of the dye absorption peak. When the incident light is tilted, the blue shift of the Bragg position results in more overlap with the dye absorption peak, generating a higher efficiency that partially compensates the reduced photon flux due to light inclination. Moreover, the unique structure of the vertically aligned TiO2 nanotubes contributes an additional scattering effect when the incident light is tilted. As a result, the power output of a DSSC coupled with the NT PC layer shows a much flatter angular dependence than a DSSC without the NT PC. At all the incident angles, the DSSC coupled with the NT PC layer also shows a higher power conversion efficiency than the one without. The concept of using NT PC to mitigate the angular dependence of DSSCs can be easily extended to many other optoelectronic devices that are irradiance sensitive. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03712j

  2. Reversible suppression of second harmonic generation in dye-doped liquid crystal by light-induced thermal phase transition on sub-micrometer scale

    NASA Astrophysics Data System (ADS)

    Zhuo, Guan-Yu; Chen, Kuan-Chieh; Lai, Kai-Wen; Wang, Chao-Ran; Chao, Chih-Yu; Chu, Shi-Wei

    2015-02-01

    Optically controllable signals are fundamental to various applications from communication to super-resolution imaging. However, literature on non-fluorescent, nonlinear optical signals that can be reversibly turned on/off on a sub-micrometer scale is scant. In this work, we experimentally demonstrate a scheme for the reversible suppression of second harmonic generation (SHG) based on dye-doped nematic liquid crystal molecules. Under a pump (suppressing SHG) and probe (generating SHG) setup with a tightly focusing microscope and a time-gated detection, outstanding modulation depth (>80%) has been realized. Surprisingly, the mechanism of liquid crystal SHG switch on a sub-micrometer scale was found to be light-induced thermal phase transition as against optical Frederick's transition. Quantitative analysis of the optical nonlinearity ? ( 2 ) versus local heating shows an excellent agreement of SHG signal suppression as well as its dependence on the liquid crystal molecular order and phase change. Our work provides an innovative example of applying nonlinear optical properties of soft materials, and can be further optimized for all-optical modulation applications.

  3. Role of Laccase and Low Molecular Weight Metabolites from Trametes versicolor in Dye Decolorization

    PubMed Central

    Moldes, Diego; Fernández-Fernández, María; Sanromán, M. Ángeles

    2012-01-01

    The studies regarding decolorization of dyes by laccase may not only inform about the possible application of this enzyme for environmental purposes, but also may provide important information about its reaction mechanism and the influence of several factors that could be involved. In this paper, decolorization of crystal violet and phenol red was carried out with different fractions of extracellular liquids from Trametes versicolor cultures, in order to describe the role of laccase in this reaction. Moreover, the possible role of the low molecular weight metabolites (LMWMs) also produced by the fungus was evaluated. The results confirm the existence of a nonenzymatic decolorization factor, since the nonprotein fraction of the extracellular liquids from cultures of T. versicolor has shown decolorization capability. Several experiments were performed in order to identify the main compounds related to this ability, which are probably low molecular weight peroxide compounds. PMID:22566767

  4. Synthesis, spectroscopic and thermal properties of nickel (II)–azo complexes with blue-violet light wavelength

    Microsoft Academic Search

    Fuxin Huang; Yiqun Wu; Donghong Gu; Fuxi Gana

    2005-01-01

    A novel azo dye containing isoxazole ring and ?-diketone derivative (TIAD) and its two nickel (II) complexes (Ni (II)–ETIAD and Ni (II)–HTIAD) were synthesized in order to obtain a blue-violet light absorption and better thermal stability as a promising organic storage material for next generation of high density digital versatile disc-recordable (HD-DVD-R) systems that uses a high numerical aperture of

  5. Glasses Transparent to Ultra-violet Radiation

    Microsoft Academic Search

    A. R. Wood; M. N. Leathwood

    1929-01-01

    DURING the past few months an investigation has been carried out in this laboratory upon the transparency of various ultra-violet transmitting glasses under different conditions. In view of the conflicting statements that have been made concerning the behaviour of these glasses, the results are of considerable interest.

  6. Ultra-violet Absorption of Sea Water

    Microsoft Academic Search

    F. A. J. ARMSTRONG; G. T. BOALCH

    1961-01-01

    The intensity of submarine daylight is of such importance to the growth of marine plants that much attention has been given to measurements of the absorption of solar radiation by sea water. It has long been known that absorption is least in the blue green in the visible spectrum, and Tsukamoto (1927) showed that the absorption of ultra-violet radiation increased

  7. The Swift Ultra-Violet\\/Optical Telescope

    Microsoft Academic Search

    Peter W. A. Roming; Thomas E. Kennedy; Keith O. Mason; John A. Nousek; Lindy Ahr; Richard E. Bingham; Patrick S. Broos; Mary J. Carter; Barry K. Hancock; Howard E. Huckle; S. D. Hunsberger; Hajime Kawakami; Ronnie Killough; T. Scott Koch; Michael K. Mclelland; Kelly Smith; Philip J. Smith; Juan Carlos Soto; Patricia T. Boyd; Alice A. Breeveld; Stephen T. Holland; Mariya Ivanushkina; Michael S. Pryzby; Martin D. Still; Joseph Stock

    2005-01-01

    The Ultra-Violet\\/Optical Telescope (UVOT) is one of three instruments flying aboard the Swift Gamma-ray Observatory. It is designed to capture the early (?1 min) UV and optical photons from the afterglow of gamma-ray\\u000a bursts in the 170–600 nm band as well as long term observations of these afterglows. This is accomplished through the use\\u000a of UV and optical broadband filters

  8. Ultra Violet Imaging Telescope (UVIT) on ASTROSAT

    NASA Astrophysics Data System (ADS)

    Kumar, Amit; Ghosh, S. K.; Hutchings, J.; Kamath, P. U.; Kathiravan, S.; Mahesh, P. K.; Murthy, J.; Nagbhushana, S.; Pati, A. K.; Rao, M. N.; Rao, N. K.; Sriram, S.; Tandon, S. N.

    2012-09-01

    The Ultra Violet Imaging Telescope on ASTROSAT Satellite mission is a suite of Far Ultra Violet (FUV: 130 - 180 nm), Near Ultra Violet (NUV: 200 - 300 nm) and Visible band (VIS: 320-550nm) imagers. ASTROSAT is the multi-wavelength mission of ISRO. UVIT will image the sky simultaneously in three channels with a field of view diameter of ~ 28 arcminutes and an angular resolution < 1.8". Two identical co-aligned telescopes (T1, T2) of Ritchey-Chretien configuration (Primary mirror of ~375 mm diameter) collect the celestial radiation and feed the detector systems via a selectable filter on a filter wheel mechanism; gratings are available in the filter wheels of FUV and NUV channels for slitless low-resolution spectroscopy. The photon-counting detector system for each of the 3 channels is generically identical. One of the telescopes images in the FUV channel, while the other images in NUV and VIS channels via a beamsplitter. Images from the VIS channel are principally used for measuring drift, used in construction of images on the ground by shift and add, and to reconstruct absolute aspect of the images. Adequate baffling has been provided for reducing the scattered background from the Sun, earth albedo and other bright objects. The one-time opening mechanical cover on each telescope also works as a Sun-shield after deployment. We will present the overall (mechanical, optical and electrical) design of the payload.

  9. Diffusion of dye solution in the intermolecular nanostructure of polydimethylsiloxane

    NASA Astrophysics Data System (ADS)

    Saito, Mitsunori; Nishimura, Tatsuya; Sakiyama, Kohei; Nakagawa, Michinori

    2012-09-01

    Polydimethylsiloxane (PDMS) contains a large, flexible free space between weakly-bonded molecules, which allows notable molecular diffusion. A toluene solution of diarylethene (photochromic dye) was mixed with a PDMS oil, and then the mixture was cured in a glass vessel by adding a curing agent. Violet laser (405 nm wavelength) irradiation induced an absorption band at around 530 nm, and consequently, the irradiated portion exhibited a red color. The colored portion gradually expanded to the entire sample because of diffusion of the dye molecules. This diffusion characteristic was used for improving an organic dye durability against a photo-induced degradation.

  10. Regression analysis for the sorption isotherms of basic dyes on sugarcane dust

    Microsoft Academic Search

    Yuh-Shan Ho; Wen-Ta Chiu; Chung-Chi Wang

    2005-01-01

    The sorption of three basic dyes, named basic violet 10, basic violet 1, and basic green 4, from aqueous solutions onto sugarcane dust was studied. The results revealed the potential of sugarcane dust, a waste material, to be a low-cost sorbent. Equilibrium isotherms were analyzed using the Langmuir, the Freundlich, and the three-parameter Redlich–Peterson isotherms. In order to determine the

  11. Spontaneous crystalization and aggregation of DCNP pyrazoline-based organic dye as a way to tailor random lasers

    NASA Astrophysics Data System (ADS)

    Cyprych, K.; Sznitko, L.; Morawski, O.; Miniewicz, A.; Rau, I.; Mysliwiec, J.

    2015-03-01

    The 3-(1,1-dicyanoethenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (DCNP) compound is showing versatile optical features including nonlinear optical effects, photoluminescence and stimulated emission resulting from its molecular design as well as polar alignment in crystal lattice. We present detailed studies carried out for the DCNP compound on a photoluminescence phenomenon, showing that its emission properties are strongly different for molecular and aggregated forms. Experiments have proved that stimulated emission can occur only from the crystaline form of DCNP and the precipitation of it from a solution leads to the constitution of gain and different, random feedback mechanisms depending on aggregate size. The immobilization of DCNP crystals and the controlled crystalization in a viscous biopolymeric matrix have been utilized to generate random micro-cavities, that support weak light localization and coherent random laser emission.

  12. Hair Dyes

    Microsoft Academic Search

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

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

  13. Size-controlled anatase titania single crystals with octahedron-like morphology for dye-sensitized solar cells.

    PubMed

    Shiu, Jia-Wei; Lan, Chi-Ming; Chang, Yu-Cheng; Wu, Hui-Ping; Huang, Wei-Kai; Diau, Eric Wei-Guang

    2012-12-21

    A simple hydrothermal method with titanium tetraisopropoxide (TTIP) as a precursor and triethanolamine (TEOA) as a chelating agent enabled growth in the presence of a base (diethylamine, DEA) of anatase titania nanocrystals (HD1-HD5) of controlled size. DEA played a key role to expedite this growth, for which a biphasic crystal growth mechanism is proposed. The produced single crystals of titania show octahedron-like morphology with sizes in a broad range of 30-400 nm; a typical, extra large, octahedral single crystal (HD5) of length 410 nm and width 260 nm was obtained after repeating a sequential hydrothermal treatment using HD3 and then HD4 as a seed crystal. The nanocrystals of size ~30 nm (HD1) and ~300 nm (HD5) served as active layer and scattering layer, respectively, to fabricate N719-sensitized solar cells. These HD devices showed greater V(OC) than devices of conventional nanoparticle (NP) type; the overall device performance of HD attained an efficiency of 10.2% power conversion at a total film thickness of 28 ?m, which is superior to that of a NP-based reference device (? = 9.6%) optimized at a total film thickness of 18-20 ?m. According to results obtained from transient photoelectric and charge extraction measurements, this superior performance of HD devices relative to their NP counterparts is due to the more rapid electron transport and greater TiO(2) potential. PMID:23116194

  14. Photodegradation of organic dyes in the presence of [Fe(III)-salen]Cl complex and H2O2 under visible light irradiation.

    PubMed

    Gazi, Sarifuddin; Rajakumar, Ananthakrishnan; Singh, N D Pradeep

    2010-11-15

    Photodegradation of persistent organic dyes (Rhodamine B (RhB), Malachite Green Oxalate (MG) and Crystal Violet 10B (CV)) is studied with Fe(III)-salen complex (?(max) 494 nm), and hydrogen peroxide under visible light irradiation (??400 nm). The complete decolourization of the dyes (60 mg/L each) was achieved in the aqueous medium. The pseudo-first-order degradation rate constants of RhB, MG, CV were found to be 2.83×10(-3) s(-1), 1.57×10(-3) s(-1) and 1.34×10(-3) s(-1), respectively. The effect of various parameters like concentration of H(2)O(2), pH of the medium, and influence of electrolytes are investigated on the degradation of RhB. A modified benzoic acid hydroxylation method has been used to detect the active oxygen species (OH radicals) in this study. The hydroxyl radical production is increased with the increase in irradiation time. Interestingly, even an excess amount of scavenger could not arrest the degradation of the dyes. This may be due to the formation of some secondary oxidants. Here, active ferryl ion was identified as the secondary oxidant. Degradation products of the dye (RhB) were determined by GC-MS, and phthalic acid was identified as the major one. From the results, a possible photodegradation mechanism has been proposed. PMID:20800350

  15. Development of dye-sensitized solar cells composed of liquid crystal embedded, electrospun poly(vinylidene fluoride-co-hexafluoropropylene) nanofibers as polymer gel electrolytes.

    PubMed

    Ahn, Sung Kwang; Ban, Taewon; Sakthivel, P; Lee, Jae Wook; Gal, Yeong-Soon; Lee, Jin-Kook; Kim, Mi-Ra; Jin, Sung-Ho

    2012-04-01

    In order to overcome the problems associated with the use of liquid electrolytes in dye-sensitized solar cells (DSSCs), a new system composed of liquid crystal embedded, polymer electrolytes has been developed. For this purpose, three types of DSSCs have been fabricated. The cells contain electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (e-PVdF-co-HFP) polymer gel electrolyte, with and without doping with the liquid crystal E7 and with a liquid electrolyte. The morphologies of the newly prepared DSSCs were explored using field emission scanning electron microscopy (FE-SEM). Analysis of the FE-SEM images indicate that the DSSC composed of E7 embedded on e-PVdF-co-HFP polymer gel electrolyte has a greatly regular morphology with an average diameter. The ionic conductivity of E7 embedded on e-PVdF-co-HFP polymer gel electrolyte was found to be 2.9 × 10(-3) S/cm at room temperature, a value that is 37% higher than that of e-PVdF-co-HFP polymer gel electrolyte. The DCCS containing the E7 embedded, e-PVdF-co-HFP polymer gel electrolyte was observed to possess a much higher power conversion efficiency (PCE = 6.82%) than that of an e-PVdF-co-HFP nanofiber (6.35%). In addition, DSSCs parameters of the E7 embedded, e-PVdF-co-HFP polymer gel electrolyte (V(oc) = 0.72 V, J(sc) = 14.62 mA/cm(2), FF = 64.8%, and PCE = 6.82% at 1 sun intensity) are comparable to those of a liquid electrolyte (V(oc) = 0.75 V, J(sc) = 14.71 mA/cm(2), FF = 64.9%, and PCE = 7.17%, both at a 1 sun intensity). PMID:22422008

  16. Orientation and electronic structure of ion exchanged dye molecules on mica: An X-ray absorption study

    SciTech Connect

    Fischer, D.; Caseri, W.R.; Haehner, G. [ETH Zuerich (Switzerland)] [ETH Zuerich (Switzerland)

    1998-02-15

    Dye molecules are frequently used to determine the specific surface area and the ion exchange capacity of high-surface-area materials such as mica. The organic molecules are often considered to be planar and to adsorb in a flat orientation. In the present study the authors have investigated the orientation and electronic structure of crystal violet (CV) and malachite green (MG) on muscovite mica, prepared by immersing the substrates for extended periods into aqueous solutions of the dyes of various concentrations. The K{sup +} ions of the mica surface are replaced by the organic cations via ion exchange. X-ray photoelectron spectroscopy reveals that only one amino group is involved in the interaction of CV and MG with the muscovite surface, i.e., certain resonance structures are abolished upon adsorption. With near edge X-ray absorption fine structure spectroscopy a significant tilt angle with respect to the surface was found for all investigated species. A flat orientation, as has often been proposed before, can effectively be ruled out. Hence, results are in marked contrast to the often quoted orientation and suggest that the specific surface areas determined with dyes may, in general, be overestimated.

  17. Crystal Structures of Two Novel Dye-Decolorizing Peroxidases Reveal a Beta-Bar Fold With a Conserved Heme-Binding Motif

    SciTech Connect

    Zubieta, C.; Krishna, S.S.; Kapoor, M.; Kozbial, P.; McMullan, D.; Axelrod, H.L.; Miller, M.D.; Abdubek, P.; Ambing, E.; Astakhova, T.; Carlton, D.; Chiu, H.J.; Clayton, T.; Deller, M.C.; Duan, L.; Elsliger, M.A.; Feuerhelm, J.; Grzechnik, S.K.; Hale, J.; Hampton, E.; Han, G.W.; /JCSG /SLAC, SSRL /Burnham Inst. Med. Res. /UC, San Diego /Scripps Res. Inst. /Novartis Res. Found.

    2007-10-31

    BtDyP from Bacteroides thetaiotaomicron (strain VPI-5482) and TyrA from Shewanella oneidensis are dye-decolorizing peroxidases (DyPs), members of a new family of heme-dependent peroxidases recently identified in fungi and bacteria. Here, we report the crystal structures of BtDyP and TyrA at 1.6 and 2.7 Angstroms, respectively. BtDyP assembles into a hexamer, while TyrA assembles into a dimer; the dimerization interface is conserved between the two proteins. Each monomer exhibits a two-domain, {alpha}+{beta} ferredoxin-like fold. A site for heme binding was identified computationally, and modeling of a heme into the proposed active site allowed for identification of residues likely to be functionally important. Structural and sequence comparisons with other DyPs demonstrate a conservation of putative heme-binding residues, including an absolutely conserved histidine. Isothermal titration calorimetry experiments confirm heme binding, but with a stoichiometry of 0.3:1 (heme:protein).

  18. Fluorescence enhancement of dyes embedded in nanoparticles of Lu, Eu, Al, and Sc diketonates of different composition and concentration

    NASA Astrophysics Data System (ADS)

    Mironov, L. Yu.; Sveshnikova, E. B.; Ermolaev, V. L.

    2014-12-01

    We have studied the effect of central ions (Lu(III), Eu(III), Sc(III), and Al(III)), organic ligands (2-naphthoyltrifluoroacetone (NTA) and p-phenylbenzoyltrifluoroacetone (PhBTA)), and their concentration in a water-alcohol solution on the fluorescence of ?-diketonate complexes formed and nanoparticles (NPs) generated by the self-assembly of these complexes. The fluorescence quenching of ligands of the complexes of nanoparticles because of the introduction of molecules of dyes, such as Nile Blue (NB), Lissamine Rhodamine RB-200 (RB), and Crystal Violet (CV), in these nanoparticles is investigated, and the NP-sensitization of the fluorescence of these dyes is explored. The dependence of the intensity of the NP-sensitized fluorescence of NB on its concentration in nanoparticles consisting of complexes that differ in composition and concentration is studied. By analyzing this dependence for the nanoparticles consisting of Sc(NTA)3, the size of the studied nanoparticles is evaluated. It is shown that the nature of this dependence is determined by a competition of two processes: the migration of the excitation energy over complexes to dyes and the migration of the excitation energy of dyes to impurities or dimer of dyes. The size of nanoparticles is compared to the estimated values of the exciton diffusion length and the critical radius of energy transfer from complexes to NB. An energy transfer of close to 100% from the nanoparticles formed of 10 ?M of Sc(NTA)3 to 50 nM of NB molecules embedded therein is observed. The introduction of NB molecules into nanoparticles leads to a 200-fold increase in fluorescence intensity compared to their direct excitation in solution.

  19. 75 FR 14468 - Carbazole Violet Pigment 23 From China and India

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ...731-TA-1060-1061 (Review)] Carbazole Violet Pigment 23 From China and India AGENCY: United...countervailing duty order on carbazole violet pigment 23 from India and the antidumping duty orders on carbazole violet pigment 23 from China and...

  20. Evolutionary replacement of UV vision by violet vision in fish

    E-print Network

    Yokoyama, Shozo

    understood why and how these func- tional changes have occurred. Here, we cloned the pigment of scabbardfish not only the molecular basis of phenotypic adaptations, but also the genetics of UV and violet vision humans, have switched from UV vision to violet vision even when they receive abundant UV light

  1. Dye Painting with Fiber Reactive Dyes

    ERIC Educational Resources Information Center

    Benjamin-Murray, Betsy

    1977-01-01

    In her description of how to use dyes directly onto fabrics the author lists materials to be used, directions for mixing dyes, techniques for applying dyes, references for additional reading and sources for dye materials. Preceding the activity with several lessons in design and other textile techniques with the dye process will ensure a…

  2. Optically tunable/switchable omnidirectionally spherical microlaser based on a dye-doped cholesteric liquid crystal microdroplet with an azo-chiral dopant.

    PubMed

    Lin, Jia-De; Hsieh, Meng-Hung; Wei, Guan-Jhong; Mo, Ting-Shan; Huang, Shuan-Yu; Lee, Chia-Rong

    2013-07-01

    This paper presents an optically wavelength-tunable and intensity-switchable dye-doped cholesteric liquid crystal (DDCLC) spherical microlaser with an azo-chiral dopant. Experimental results present that two functions of optical control - tunability of lasing wavelength and switchability of lasing intensity - can be obtained for this spherical microlaser at low and high intensity regimes of non-polarized UV irradiation, respectively. If the DDCLC microdroplet is subjected to weak UV irradiation, azo-chiral molecules may transform to the bent cis state at a low concentration rate. The effect can slightly decrease the local order of LCs and thus the helical twisting power of the CLC in the microdroplet. As a result, the CLC pitch may become slightly elongated, which will cause the gradual red-shift of both omnidirectional PBG and lasing emission of the DDCLC spherical microdroplet. In contrast, when the microdroplet is subjected to strong UV irradiation, numerous azo-chiral molecules may simultaneously change to bent cis-isomers to seriously disarrange the helical texture of the CLC, which will quickly deform the PBG and deactivate the lasing emission of the microdroplet. Prolonged irradiation of a blue beam after strong UV irradiation may cause the cis azo-chiral molecules quickly convert back rod-like trans-isomers, which may then regenerate the CLC Bragg onion and PBG structures and reactivate the lasing emission of the microdroplet. Optical control of the DDCLC spherical microlaser is realized on a scale of seconds and minutes when UV irradiation is strong and weak, respectively. The 3D DDCLC spherical microlaser is a highly promising controllable 3D micro-light source or microlaser (e.g., all-optical 3D single photon microlaser) for applications of 3D all-optical integrated photonics, laser displays, and biomedical imaging and therapy, and as a 3D UV microdosagemeter or microsensor. PMID:23842363

  3. Determination of leucogentian violet and gentian violet in catfish tissue by high-performance liquid chromatography with visible detection

    Microsoft Academic Search

    Larry G. Rushing; Sharon F. Webb; Harold C. Thompson

    1995-01-01

    A sensitive analytical procedure for the determination of residues of leucogentian violet (LGV) and gentian violet (GV) in catfish tissue is presented. Frozen (?20°C) catfish fillets were cut into chunks and then blended in a Waring blendor. A 10-g amount of catfish muscle tissue was homogenized and extracted with acetonitrile-buffer, partitioned against methylene chloride, and cleaned up on tandem neutral

  4. Determination of textile dyes in organs of Oncorhynchus mykiss W. after in vitro exposure

    Microsoft Academic Search

    M. C. Riva; R. Flos; M. Crespi; M. Pepió

    1992-01-01

    The quantitative determination in organs of Oncorhynchus mykiss W. of a premetallized dye (C.I. Acid Violet 66) and the azoic base (C.I. Acid Red 217), used in wool dyeing, is studied in this paper. UV-VIS Spectrophotometry was used for the chromatic quantification and atomic absorption spectrophotometry for the detection of the metal. The method described here is as satisfactory for

  5. Decolorization of textile dye by Candida albicans isolated from industrial effluents

    Microsoft Academic Search

    Vivian Vitor; Carlos Renato Corso

    2008-01-01

    The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by\\u000a Candida albicans isolated from industrial effluents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions.\\u000a A comparative

  6. Decolorization Screening of Synthetic Dyes by Anaerobic Methanogenic Sludge Using a Batch Decolorization Assay

    Microsoft Academic Search

    Haresh Keharia; Hardik Patel; Datta Madamwar

    2004-01-01

    The nonspecific ability of anaerobic sludge bacteria obtained from cattle dung slurry was investigated for 17 different dyes\\u000a in a batch assay system using sealed serum vials. Experiments using Reactive Violet 5 (RV 5) showed that sludge bacteria could\\u000a effectively decolorize solutions having dye concentrations up to 1000 mg l?1 with a decolorization efficiency of above 75% during 48 h

  7. Biosorption of Basic Violet 5BN and Basic Green by waste brewery’s yeast from single and multicomponent systems

    Microsoft Academic Search

    Yunhai Wu; Li Jiang; YaJun Wen; JianXin Zhou; Shixun Feng

    Background and aim  The biosorption of Basic Violet 5BN (BV) and Basic Green (BG) by waste brewery’s yeast (WBY) from single and binary systems\\u000a was investigated.\\u000a \\u000a \\u000a \\u000a \\u000a Results and discussion  For the single system, the adsorption of both dyes is pH-dependent and the optimum value is 5.0. At a lower initial concentration,\\u000a the kinetic data agree well with both pseudo-first-order and pseudo-second-order models,

  8. Brominated precursors of Tyrian purple (C.I. Natural Violet 1) from Plicopurpura pansa, Plicopurpura columellaris and Plicopurpura patula

    Microsoft Academic Search

    Felipe Javier López Chávez; Patricia Ríos Chávez; Ken Oyama

    2009-01-01

    Tyrian purple (C.I. Natural Violet 1) and its precursors have enjoyed much attention as various species of gastropods of the Muricidae family. However, few investigations have concerned the dye's precursors, namely Plicopurpura columellaris and Plicopurpura patula. Derivatization and NMR revealed that the purple pigment in Plicopurpura pansa is 6,6?-dibromoindigo. 1H and 13C NMR enabled tyrindolinone (6-bromo-2,2-bis-methylsulfanyl-1,2-dihydro-3H-indol-3-one), a methanethiol adduct of

  9. Dyeing properties of natural dyes extracted from eucalyptus

    Microsoft Academic Search

    S. Ali; N. Nisar; T. Hussain

    2007-01-01

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

  10. EPR and LC-MS studies on the mechanism of industrial dye decolorization by versatile peroxidase from Bjerkandera adusta.

    PubMed

    Baratto, Maria Camilla; Juarez-Moreno, Karla; Pogni, Rebecca; Basosi, Riccardo; Vazquez-Duhalt, Rafael

    2015-06-01

    The mechanisms of industrial dye transformation by versatile peroxidase were elucidated. Purified versatile peroxidase from Bjerkandera adusta was able to decolorize different classes of dyes including azo and phthalocyanines, but unable to transform any of the anthraquinones tested. Kinetic constants for selected dyes were determined and the transformation products were analyzed by EPR spectroscopy and mass spectrometry. The EPR and MS analyses of the enzymatic decolorization products showed the cleavage of the azo bond in azo dyes and the total disruption of the phthalocyaninic ring in phthalocyanine dyes. The EPR analysis on two copper-containing dyes, reactive violet 5 (azo) and reactive blue 72 (phthalocyanine), showed that the transformation can or not break the metal-ion coordination bond according the dye nature. The role of the catalytic Trp172 in the dye transformation by a long-range electron transfer pathway was confirmed and the oxidation mechanisms are proposed and discussed. PMID:25567062

  11. Photodegradation of Acid Violet 7 with AgBr-ZnO under highly alkaline conditions.

    PubMed

    Krishnakumar, B; Swaminathan, M

    2012-12-01

    The photocatalytic activity of AgBr-ZnO was investigated for the degradation of Acid Violet 7 (AV 7) in aqueous solution using UV-A light. AgBr-ZnO is found to be more efficient than commercial ZnO and prepared ZnO at pH 12 for the mineralization of AV 7. The effects of operational parameters such as the amount of photocatalyst, dye concentration, initial pH on photo mineralization have been analyzed. Expect oxone, other oxidants decrease the degradation efficiency. Addition of metal ions and anions decrease the degradation efficiency of AgBr-ZnO significantly. The mineralization of AV 7 has also been confirmed by COD measurements. The mechanism of degradation by AgBr-ZnO is proposed to explain its higher activity under UV light. The catalyst is found to be reusable. PMID:23063859

  12. Bioremediation of Dyes in Textile Effluents by Aspergillus oryzae

    Microsoft Academic Search

    Carlos Renato Corso; Ana Carolina Maganha de Almeida

    2009-01-01

    In this study Aspergillus oryzae was utilized to remove azo dyes from aqueous solution. Physically induced in its paramorphogenic form to produce standardized\\u000a mycelial pellets, the non-autoclaved and autoclaved hyphae biomass was applied to biosorb the reactive dyes Procion Red HE7B\\u000a (PR-HE7B) and Procion Violet H3R (PV-H3R) at different pH values (2.50, 4.50, and 6.50). The best pH for biosorption

  13. Crystals

    NSDL National Science Digital Library

    Lawrence Hall of Science

    2009-01-01

    In this earth science/math/art activity, learners use simple ingredients to grow crystals and examine the repeating geometric shapes and patterns. Learners compare the growth of crystals from four types of crystal-starters (table salt, Borax, sand, and Epsom salt) to see which starter grows the most crystals in 14 days. Learners report their results online and find out what other learners discovered. Afterward, learners can use the crystals they grew to create works of art.

  14. Competitive adsorption of dyes and heavy metals on zeolitic structures.

    PubMed

    Hernández-Montoya, V; Pérez-Cruz, M A; Mendoza-Castillo, D I; Moreno-Virgen, M R; Bonilla-Petriciolet, A

    2013-02-15

    The adsorption of Acid blue 25, basic blue 9, basic violet 3, Pb(2+), Ni(2+), Zn(2+) and Cd(2+) ions has been studied in single and dye-metal binary solutions using two mineral materials: Clinoptilolite (CL) and ER (Erionite). These zeolites were characterized by FT-IR spectroscopy; potentiometric titration and nitrogen adsorption isotherms at 77 K to obtain their textural parameters. Results indicated that ER has an acidic character and a high specific surface (401 m(2) g(-1)) in contrast with the zeolite CL (21 m(2) g(-1)). Surprisingly, the removal of dyes was very similar for the two zeolites and they showed a considerable selectivity by the basic dyes in comparison with the acid dyes. In the case of heavy metals, ER was more effective in the adsorption process showing a selectivity of: Pb(2+) > Ni(2+) > Zn(2+) > Cd(2+). In the multicomponent adsorption experiments an antagonistic effect was observed in the removal of basic dyes and heavy metals. Particularly, the adsorbed amount of basic violet 3 decreased more significantly when the heavy metals are presents in contrast with the basic blue 9. PMID:23321372

  15. Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS

    PubMed Central

    2012-01-01

    Background The discharge of wastewater that contains high concentrations of reactive dyes is a well-known problem associated with dyestuff activities. In recent years, semiconductor photocatalysis has become more and more attractive and important since it has a great potential to contribute to such environmental problems. One of the most important aspects of environmental photocatalysis is in the selection of semiconductor materials like ZnO and TiO2, which are close to being two of the ideal photocatalysts in several respects. For example, they are relatively inexpensive, and they provide photo-generated holes with high oxidizing power due to their wide band gap energy. In this work, nanostructural ZnO film on the Zn foil of the Alkaline-Manganese Dioxide-Zinc Cell was fabricated to degrade EV dye. The major innovation of this paper is to obtain the degradation mechanism of ethyl violet dyes resulting from the HPLC-PDA-ESI-MS analyses. Results The fabrication of ZnO nanostructures on zinc foils with a simple solution-based corrosion strategy and the synthesis, characterization, application, and implication of Zn would be reported in this study. Other objectives of this research are to identify the reaction intermediates and to understand the detailed degradation mechanism of EV dye, as model compound of triphenylmethane dye, with active Zn metal, by HPLC-ESI-MS and GC-MS. Conclusions ZnO nanostructure/Zn-foils had an excellent potential for future applications on the photocatalytic degradation of the organic dye in the environmental remediation. The intermediates of the degradation process were separated and characterized by the HPLC-PDA-ESI-MS and GC-MS, and twenty-six intermediates were characterized in this study. Based on the variation of the amount of intermediates, possible degradation pathways for the decolorization of dyes are also proposed and discussed. PMID:22748361

  16. Dye-sensitized photocathodes: efficient light-stimulated hole injection into p-GaP under depletion conditions.

    PubMed

    Chitambar, Michelle; Wang, Zhijie; Liu, Yiming; Rockett, Angus; Maldonado, Stephen

    2012-06-27

    The steady-state photoelectrochemical responses of p-GaP photoelectrodes immersed in aqueous electrolytes and sensitized separately by six triphenylmethane dyes (rose bengal, rhodamine B, crystal violet, ethyl violet, fast green fcf, and brilliant green) have been analyzed. Impedance measurements indicated that these p-GaP(100) photoelectrodes operated under depletion conditions with an electric field of ?8.5 × 10(5) V cm(-1) at the p-GaP/solution interface. The set of collected wavelength-dependent quantum yield responses were consistent with sensitization occurring specifically from adsorbed triphenylmethane dyes. At high concentrations of dissolved dye, the measured steady-state photocurrent-potential responses collected at sub-bandgap wavelengths suggested unexpectedly high (>0.1) net internal quantum yields for sensitized hole injection. Separate measurements performed with rose bengal adsorbed on p-GaP surfaces pretreated with (NH(4))(2)S verified efficient sensitized hole injection. A modified version of wxAMPS, a finite-difference software package, was utilized to assess key operational features of the sensitized p-GaP photocathodes. The net analysis showed that the high internal quantum yield values inferred from the experimental data were most likely afforded by the internal electric field present within p-GaP, effectively sweeping injected holes away from the interface and minimizing their participation in deleterious pathways that could limit the net collection yield. These simulations defined effective threshold values for the charge carrier mobilities (?10(-6) cm(2) V(-1) s(-1) and ?10(-1) cm(2) V(-1) s(-1) at dopant densities of 10(18) and 10(13) cm(-3), respectively), hole injection rate constants (?10(12) s(-1)), and surface trap densities (10(12) cm(-2)) needed to attain efficient hole collection with the quality of p-GaP materials used here. The cumulative experimental and modeling data thus provide insight on design strategies for assembling new types of dye-sensitized photocathodes that operate under depletion conditions. PMID:22734693

  17. Investigation of optoelectronic properties of N3 dye-sensitized TiO2 nano-crystals by hybrid methods: ONIOM (QM/MM) calculations

    NASA Astrophysics Data System (ADS)

    Oftadeh, Mohsen; Tavakolizadeh, Leila

    2013-04-01

    In this article, Ru(4,4'-dicarboxy-2,2'-bipyridine)2(NCS)2 dye (N3) and some derivatives were investigated using Density Functional Theory (DFT) calculations in solution to elucidate the influence of the environment and substituted groups on electronic properties. Full geometry optimization and investigation of electronic properties of N3 dye and some derivatives were performed using DFT and HF calculations. The singlet ground state geometries were fully optimized at the B3LYP/3-21G** level of theory through the Gaussian 98 program. Based on the computed results, the optoelectronic properties are sensitive to chemical solvent environments. Moreover, the properties of anatase cluster (TiO2) models have been investigated, and N3 dyes have been adsorbed on TiO2 nano-particle with diprotonated states. The modified N3 dyes highly affected the electronic structure. This leads to significant changes in the adsorption spectra as compared to the N3 dyes. Through hybrid methods, the properties of interfacial electronic coupling of the combined system were estimated. The results of some combined systems showed that the electronic coupling, lowest lowest unoccupied molecular orbitals, and the TiO2 conduction band resided in the visible region.

  18. Biosorption potential of synthetic dyes by heat-inactivated and live Lentinus edodes CCB-42 immobilized in loofa sponges.

    PubMed

    Gimenez, Gabriela Gregolin; Ruiz, Suelen Pereira; Caetano, Wilker; Peralta, Rosane Marina; Matioli, Graciette

    2014-12-01

    Lentinus edodes CCB-42 was immobilized in loofa sponges and applied to the biosorption of the synthetic dyes congo red, bordeaux red and methyl violet. Live immobilized microorganisms achieved average decolorations of congo red, bordeaux red and methyl violet of 97.8, 99.7 and 90.6 %, respectively. The loofa sponge was the support and the coadjuvant promoting dye adsorption. The biosorption conditions were optimized for each dye, yielding 30 °C, pH 5.0 and a 12 h reaction time for congo red; 25 °C, pH 3.0 and 36 h for bordeaux red; and 25 °C, pH 8.0 and 24 h for methyl violet. Operational stability was evaluated over five consecutive cycles, with both bordeaux red and congo red exhibiting decolorations above 90 %, while the decoloration of methyl violet decreased after the third cycle. In the sixth month of storage, congo red, bordeaux red and methyl violet had decolorations of 93.1, 79.4 and 73.8 %, respectively. Biosorption process best fit the pseudo-second-order kinetic and Freundlich isotherm models. Maximum biosorption capacity of heat-treated L. edodes immobilized in loofa sponge was determined as 143.678, 500.00 and 381.679 mg/g for congo red, bordeaux red and methyl violet, respectively. Treatment with immobilized L. edodes reduced the phytotoxicity of the medium containing dyes. FT-Raman experiments suggested the occurrence of interactions between loofa sponge fibers, L. edodes and dye. L. edodes CCB-42 immobilized in loofa sponges represents a promising new mode of treatment of industrial effluents. PMID:25267474

  19. A rapid and simple method for simultaneous determination of triphenylmethane dye residues in rainbow trouts by liquid chromatography-tandem mass spectrometry.

    PubMed

    Kaplan, Muammer; Olgun, Elmas O; Karaoglu, Oznur

    2014-07-01

    A rapid and simple LC-MS/MS method was developed and optimized for screening and confirmation of triphenylmethane dyes including malachite green (MG), leucomalachite green (LMG), crystal violet (CV), leucocrystal violet (LCV) and brilliant green (BG) in fish muscle with skin. Leucocrystal violet D6 (LCV-D6) and leucomalachite green-D5 (LMG D5) was used as internal standards. Sample preparation is a simple procedure based on solid-liquid extraction with acetonitrile containing 1% acetic acid, followed by centrifugation and evaporation of the supernatant. The residue was dissolved in acetonitrile with 0.1% acetic acid and centrifuged prior to LC-MS/MS analysis. Chromatographic separation of analytes was performed on an Inertsil ODS-4 C18 column with ammonium acetate buffer in acetonitrile gradient. The mass detection was performed on a triple-quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI+). The developed method was validated according to the criteria set in Commission Decision 2002/657/EC. The decision limit (CC?) was 0.43, 0.24, 0.33, 0.28 and 0.17?gkg(-1) for MG, LMG, CV, LCV and BG respectively. The detection capability (CC?) values obtained were 0.56, 0.31, 0.43, 0.37 and 0.22?gkg(-1), respectively. The precision of the method, expressed as relative standard deviation (RSD) values for the within-day and inter-day laboratory reproducibility, for MG, LMG, CV, LCV and BG at the four levels of fortification (0.3, 0.5, 1, and 2?gkg(-1)), was less than 16 and 19% respectively. Accuracy of the method was confirmed by successful participation of a proficiency test organized by FAPAS. The method has been used for the analysis of 208 fish samples of which seven samples were found to be non-compliant containing low residues of LMG and LCV. PMID:24866565

  20. Mutagenicity testing of some commonly used dyes.

    PubMed Central

    Chung, K T; Fulk, G E; Andrews, A W

    1981-01-01

    Seventeen commonly used dyes and 16 of their metabolites or derivatives were tested in the Salmonella-mammalian microsome mutagenicity test. Mutagens active with and without added Aroclor-induced rat liver microsome preparations (S9) were 3-aminopyrene, lithol red, methylene blue (USP), methyl yellow, neutral red, and phenol red. Those mutagenic only with S9 activation were 4-aminopyrazolone, 2,4-dimethylaniline, N,N-dimethyl-p-phenylenediamine, methyl red, and 4-phenyl-azo-1-naphthylamine. Orange II was mutagenic only without added S9. Nonmutagenic azo dyes were allura red, amaranth, ponceau R, ponceau SX, sunset yellow, and tartrazine. Miscellaneous dyes not mutagenic were methyl green, methyl violet 2B, and nigrosin. Metabolites of the azo dyes that were not mutagenic were 1-amino-2-naphthol hydrochloride, aniline, anthranilic acid, cresidine salt, pyrazolone T,R-amino salt (1-amino-2-naphthol-3,6-disulfonic disodium salt), R-salt, Schaeffer's salt (2-naphthol-6-sulfonic acid, sodium salt), sodium naphthionate, sulfanilamide, and sulfanilic acid. 4-Amino-1-naphthalenesulfonic acid sodium salt was also not mutagenic. Fusobacterium sp. 2 could reductively cleave methyl yellow to N,N-dimethyl-p-phenylenediamine which was then activated to a mutagen. PMID:7039509

  1. Tunable blue–violet Cr3+:LiCAF + BiBO compact laser

    NASA Astrophysics Data System (ADS)

    Maestre, H.; Torregrosa, A. J.; Capmany, J.

    2015-03-01

    We present a compact continuous wave (CW) external-cavity tunable Cr3+:LiCaAlF6 (Cr:LiCAF) laser which is intracavity frequency doubled using a BiB3O6 (BiBO) nonlinear crystal to obtain tunable blue–violet radiation. The generated second harmonic (SH) can be tuned by means of either angular or temperature variation of the nonlinear crystal. We have obtained SH radiation between 390–415 nm and a maximum output power of 34 mW at 400 nm. Future improvements on the SH tuning range and output power are addressed in the text. Our results may be applied in the design of compact tunable composite external-cavity solid-state lasers.

  2. Just Dyeing to Find Out.

    ERIC Educational Resources Information Center

    Monhardt, Becky Meyer

    1996-01-01

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

  3. Violet and blue light blocking intraocular lenses: photoprotection versus photoreception

    PubMed Central

    Mainster, M A

    2006-01-01

    Aim To analyse how intraocular lens (IOL) chromophores affect retinal photoprotection and the sensitivity of scotopic vision, melanopsin photoreception, and melatonin suppression. Methods Transmittance spectra of IOLs, high pass spectral filters, human crystalline lenses, and sunglasses are used with spectral data for acute ultraviolet (UV)?blue photic retinopathy (“blue light hazard” phototoxicity), aphakic scotopic luminous efficiency, melanopsin sensitivity, and melatonin suppression to compute the effect of spectral filters on retinal photoprotection, scotopic sensitivity, and circadian photoentrainment. Results Retinal photoprotection increases and photoreception decreases as high pass filters progressively attenuate additional short wavelength light. Violet blocking IOLs reduce retinal exposure to UV (200–400?nm) radiation and violet (400–440?nm) light. Blue blocking IOLs attenuate blue (440–500?nm) and shorter wavelength optical radiation. Blue blocking IOLs theoretically provide better photoprotection but worse photoreception than conventional UV only blocking IOLs. Violet blocking IOLs offer similar UV?blue photoprotection but better scotopic and melanopsin photoreception than blue blocking IOLs. Sunglasses provide roughly 50% more UV?blue photoprotection than either violet or blue blocking IOLs. Conclusions Action spectra for most retinal photosensitisers increase or peak in the violet part of the spectrum. Melanopsin, melatonin suppression, and rhodopsin sensitivities are all maximal in the blue part of the spectrum. Scotopic sensitivity and circadian photoentrainment decline with ageing. UV blocking IOLs provide older adults with the best possible rhodopsin and melanopsin sensitivity. Blue and violet blocking IOLs provide less photoprotection than middle aged crystalline lenses, which do not prevent age related macular degeneration (AMD). Thus, pseudophakes should wear sunglasses in bright environments if the unproved phototoxicity?AMD hypothesis is valid. PMID:16714268

  4. 75 FR 26716 - Carbazole Violet Pigment 23 from India: Extension of Time Limit for Final Results of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-12

    ...Administration [C-533-839] Carbazole Violet Pigment 23 from India: Extension of Time Limit...countervailing duty order on carbazole violet pigment 23 (CVP-23) from India. See Carbazole Violet Pigment 23 from India: Preliminary Results...

  5. Combination of photoreactor and packed bed bioreactor for the removal of ethyl violet from wastewater.

    PubMed

    Chen, Chih-Yu; Yen, Shao-Hsiung; Chung, Ying-Chien

    2014-12-01

    An efficient treatment system that combines a photoreactor and packed bed bioreactor (PBR) was developed and evaluated for treating ethyl violet (EV)-containing wastewater. Initial experiments demonstrated that the optimal operating parameters for the photoreactor in treating EV-containing wastewater were 2h reaction time, pH of 7, and 2 min liquid retention time. Under these conditions, the photocatalytic reaction achieved a 61% EV removal efficiency and resulted in a significant BOD/COD increase in the solution. The results displayed by the coupled photobiological system achieved a removal efficiency of 85% and EC50 of the solution increased by 19 times in a semi-continuous mode when the EV concentration was <150 mg +L(-)(1). The effect of shock loading on the EV removal was temporary but coexisting substrate (glucose and crystal violet) at specific levels would affect the EV removal efficiency of the PBR. Phylogenetic analysis in the PBR indicated that the major bacteria species were Bdellovibrio bacteriovorus, Ralstonia pickettii, Stenotrophomonas maltophilia, and Comamonas sp. Furthermore, the possible degrading mechanisms of this coupled system were demethylation, deethylation, aromatic ring opening, nitrification, and carbon oxidation. The intermediates were characterized using gas chromatography-mass spectrometry analysis. These results indicated that the coupled photobiological system provides an effective method of EV removal. PMID:25259784

  6. 75 FR 52930 - Carbazole Violet Pigment 23 From India: Preliminary Results of Antidumping Duty Changed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-30

    ...Administration [A-533-838] Carbazole Violet Pigment 23 From India: Preliminary Results of Antidumping...antidumping duty order on carbazole violet pigment 23 from India to determine whether Meghmani Pigments (Meghmani) is the...

  7. HPLC Analysis of Phenolic Compounds in Field Violet

    Microsoft Academic Search

    R. A. Bubenchikov; N. F. Goncharov

    2005-01-01

    HPLC analyses revealed 40 compounds of phenolic nature in field violet (Viola arvensis L.), which belong for the most part to the classes of flavonoids, coumarins, and phenolcarboxylic acid derivatives. Eleven compounds (luteolin, apigenin, quercetin, hyperoside, hesperidin, isoferulic acid, ferulic acid, ellagic acid, dicoumarin, catechol, and arbutin) have been identified in this plant for the first time.

  8. Decolorization of basic, direct and reactive dyes by pre-treated narrow-leaved cattail (Typha angustifolia Linn.).

    PubMed

    Inthorn, Duangrat; Singhtho, Siritham; Thiravetyan, Paitip; Khan, Eakalak

    2004-09-01

    The efficiency of basic, direct and reactive dye removal from water by narrow-leaved cattail (NLC) powder treated with distilled water (DW-NLC), 37% formaldehyde+0.2 N sulfuric acid (FH-NLC), or 0.1 N sodium hydroxide (NaOH-NLC) at various pH levels (3, 5, 7, and 9) was tested. Desorption of the adsorbed dyes was also investigated. The type of NLC treatment and pH of the dye solution had little effect on removal of basic dyes, and efficiencies ranged from 97% to 99% over the range of pH used. Over a wide range of pH levels, all types of treated cattail powder had negative charges and probably attracted the basic dyes possessing positive charges. Efficiency of removal by the three NLC treatments ranged from 37% to 42% for direct dyes and from 22% to 54% for direct dyes at pH 7. The pH of the dye solution had substantial effects on the efficiency of removal in direct and reactive dyes. Dye removal was highest at pH 3, with 99% for a direct dye (Sirius Red Violet RL) and 96% for a reactive dye (Basilen Red M-5B). There was mutual attraction between negatively charged direct dye molecules and positively charged molecules on the surface of the FH-treated cattail. In tests of desorption of dyes from cattail in distilled water, the desorption percentage for FH-NLC after adsorbing basic, direct and reactive dyes was 6%, 10% and 35%, respectively, which indicated a chemisorption mechanism for basic and direct dyes and some physiosorption for reactive dyes. PMID:15182837

  9. 75 FR 27815 - Carbazole Violet Pigment 23 From China and India; Determinations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-18

    ...731-TA-1060 and 1061 (Review) Carbazole Violet Pigment 23 From China and India; Determinations...countervailing duty order on carbazole violet pigment 23 from India would be likely to lead...antidumping duty orders on carbazole violet pigment 23 from China and India would be...

  10. 75 FR 38076 - Carbazole Violet Pigment 23 from India: Final Results of Antidumping Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ...Administration [A-533-838] Carbazole Violet Pigment 23 from India: Final Results of Antidumping...antidumping duty order on carbazole violet pigment 23 (CVP 23) from India. The review...parties to comment. See Carbazole Violet Pigment 23 from India: Preliminary Results...

  11. 75 FR 977 - Carbazole Violet Pigment 23 From India: Preliminary Results of Countervailing Duty Administrative...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-07

    ...Administration [C-533-839] Carbazole Violet Pigment 23 From India: Preliminary Results of...countervailing duty order on carbazole violet pigment 23 (CVP-23) from India for the period...Countervailing Duty Order: Carbazole Violet Pigment 23 from India, 69 FR 77995...

  12. 75 FR 33243 - Carbazole Violet Pigment 23 From India: Final Results of Countervailing Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-11

    ...Administration [C-533-839] Carbazole Violet Pigment 23 From India: Final Results of Countervailing...countervailing duty order on carbazole violet pigment 23 from India for the period January 1...December 31, 2007. See Carbazole Violet Pigment 23 from India: Preliminary Results...

  13. 75 FR 29719 - Carbazole Violet Pigment 23 From India: Continuation of Countervailing Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-27

    ...Administration [C-533-839] Carbazole Violet Pigment 23 From India: Continuation of Countervailing...Countervailing Duty Order: Carbazole Violet Pigment 23 From India, 69 FR 77995 (December...order to be revoked. See Carbazole Violet Pigment 23 from India: Final Results of the...

  14. 76 FR 24855 - Carbazole Violet Pigment 23 From India: Rescission of Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ...Administration [A-533-838] Carbazole Violet Pigment 23 From India: Rescission of Administrative...antidumping duty order on carbazole violet pigment 23 (CVP 23) from India for the period...Antidumping Duty Order: Carbazole Violet Pigment 23 From India, 69 FR 77988...

  15. Light-trapping in dye-sensitized solar cells Stephen Foster* and Sajeev John

    E-print Network

    John, Sajeev

    Light-trapping in dye-sensitized solar cells Stephen Foster* and Sajeev John We demonstrate numerically that photonic crystal dye-sensitized solar cells (DSSCs) can provide at least a factor of one researched is the dye-sensitized solar cell (DSSC). These cells are inexpensive to make and boast power

  16. Anchoring properties of photoaligned azo-dye materials.

    PubMed

    Chigrinov, Vladimir; Muravski, Anatoli; Kwok, Hoi Sing; Takada, Hirokazu; Akiyama, Hidenari; Takatsu, Haruyoshi

    2003-12-01

    The photoinduced alignment of a liquid crystal (LC) on films of azo dyes was studied for the liquid crystal display applications. In order to improve the alignment stability of the photoaligned dye (SD-1), the azo-dye derivative with polymerizable terminal groups was synthesized (SDA-1). The films of SDA-1 exhibit good photoalignment properties and ultraviolet stability after thermal polymerization. We investigated the anchoring coefficient for polar and azimuthal energy for both azo-dyes SD-1 and SDA-1 using a differential method developed by us. The polar and azimuthal anchoring strengths of azo-dye aligning materials are comparable with those of usual polyimide aligning materials. The electro-optic response of a 90 degrees twisted LC cell remains almost the same after heating up to 200 degrees C, i.e., the anchoring energy remains considerably high. PMID:14754220

  17. Expansion of the Scope of AOAC First Action Method 2012.25-Single-Laboratory Validation of Triphenylmethane Dye and Leuco Metabolite Analysis in Shrimp, Tilapia, Catfish, and Salmon by LC-MS/MS.

    PubMed

    Andersen, Wendy C; Casey, Christine R; Schneider, Marilyn J; Turnipseed, Sherri B

    2015-05-01

    Prior to conducting a collaborative study of AOAC First Action 2012.25 LC-MS/MS analytical method for the determination of residues of three triphenylmethane dyes (malachite green, crystal violet, and brilliant green) and their metabolites (leucomalachite green and leucocrystal violet) in seafood, a single-laboratory validation of method 2012.25 was performed to expand the scope of the method to other seafood matrixes including salmon, catfish, tilapia, and shrimp. The validation included the analysis of fortified and incurred residues over multiple weeks to assess analyte stability in matrix at -80°C, a comparison of calibration methods over the range 0.25 to 4 ?g/kg, study of matrix effects for analyte quantification, and qualitative identification of targeted analytes. Method accuracy ranged from 88 to 112% with 13% RSD or less for samples fortified at 0.5, 1.0, and 2.0 ?g/kg. Analyte identification and determination limits were determined by procedures recommended both by the U. S. Food and Drug Administration and the European Commission. Method detection limits and decision limits ranged from 0.05 to 0.24 ?g/kg and 0.08 to 0.54 ?g/kg, respectively. AOAC First Action Method 2012.25 with an extracted matrix calibration curve and internal standard correction is suitable for the determination of triphenylmethane dyes and leuco metabolites in salmon, catfish, tilapia, and shrimp by LC-MS/MS at a residue determination level of 0.5 ?g/kg or below. PMID:26024871

  18. Cyanine dyes in solid state organic heterojunction solar cells

    NASA Astrophysics Data System (ADS)

    Heier, Jakob; Peng, Chuyao; Véron, Anna C.; Hany, Roland; Geiger, Thomas; Nüesch, Frank A.; Vismara, Marcus V. G.; Graeff, Carlos F. O.

    2014-10-01

    Today numerous cyanine dyes that are soluble in organic solvents are available, driven by more than a century of research and development of the photographic industry. Several properties specific to cyanine dyes suggest that this material class can be of interest for organic solar cell applications. The main absorption wavelength can be tuned from the ultra-violet to the near-infrared. The unparalleled high absorption coefficients allow using very thin films for harvesting the solar photons. Furthermore, cyanines are cationic polymethine dyes, offering the possibility to modify the materials by defining the counteranion. We here show specifically how counterions can be utilized to tune the bulk morphology when blended with fullerenes. We compare the performance of bilayer heterojunction and bulk heterojunction solar cells for two different dyes absorbing in the visible and the near-infrared. Light-induced Electron Spin Resonance (LESR) was used to study the charge transfers of light induced excitons between cyanine dyes and the archetype fullerene C60. LESR results show good correlation with the cell performance.

  19. Violets of the section Melanium, their colonization by arbuscular mycorrhizal fungi and their occurrence on heavy metal heaps

    Microsoft Academic Search

    A. S?omka; E. Kuta; G. Szarek-?ukaszewska; B. Godzik; P. Kapusta; G. Tylko; H. Bothe

    2011-01-01

    Violets of the sections Melanium were examined for their colonization by arbuscular mycorrhizal fungi (AMF). Heartsease (Viola tricolor) from several heavy metal soils was AMF-positive at many sites but not at extreme biomes. The zinc violets Viola lutea ssp. westfalica (blue zinc violet) and ssp. calaminaria (yellow zinc violet) were always AMF-positive on heavy metal soils as their natural habitats.

  20. Photochemistry of Cellulose in the Far Ultra-violet

    Microsoft Academic Search

    G. S. Egerton; E. Attle; M. A. Rathor

    1962-01-01

    IT is known that hydrogen, carbon monoxide and carbon dioxide are evolved, and aldehyde and carboxyl groups formed1, during the photolysis of cellulose with short-wave ultra-violet radiation in the absence of oxygen; but the complications produced by the presence of oxygen and water vapour are not fully understood. We have found that temperature markedly affects the nature of the results

  1. Thermoluminescence and Phosphorescence in Polyethylene Under Ultra-Violet Irradiation

    Microsoft Academic Search

    A. Charlesby; R. H. Partridge

    1965-01-01

    The thermoluminescence of polyethylene induced at low temperature by ultra-violet radiation has been studied and compared with that induced by gamma-radiation. Although considerable similarity exists between these two, the total thermoluminescence output under u.v.irradiation is found to be dose rate dependent, whereas under gamma-irradiation it is independent of dose rate. Study of the low temperature u.v. induced phosphorescence of polyethylene,

  2. Optofluidic dye lasers

    Microsoft Academic Search

    Zhenyu Li; Demetri Psaltis

    2008-01-01

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

  3. Blue sensitizers for solar cells: Natural dyes from Calafate and Jaboticaba

    Microsoft Academic Search

    André Sarto Polo; Neyde Yukie Murakami Iha

    2006-01-01

    Blue-violet anthocyanins from Jaboticaba (Myrtus cauliflora Mart) and Calafate (Berberies buxifolia Lam) were employed as TiO2 dye-sensitizers. Solar cells sensitized by Jaboticaba extracts achieved up to Jsc=9.0mAcm?2, Voc=0.59V, Pmax=1.9mWcm?2 and ff=0.54, while for Calafate sensitized cells the values determined were up to Jsc=6.2mAcm?2, Voc=0.47V, Pmax=1.1mWcm?2 and ff=0.36. Other natural dyes were evaluated without significant photocurrent, demonstrating that only selected extracts

  4. Dye Like A Natural

    NSDL National Science Digital Library

    Julie Yu

    2010-01-01

    In this activity, learners stain fabrics--on purpose! Learners explore the art of natural dyeing by using dyes and substrates that are both derived from plant or animal sources as well as mordant solutions. Learners compare the color and effectiveness of different mordant/dye combinations on the different substrates.

  5. Laccase/mediator assisted degradation of triarylmethane dyes in a continuous membrane reactor.

    PubMed

    Chhabra, Meenu; Mishra, Saroj; Sreekrishnan, Trichur Ramaswamy

    2009-08-10

    Laccase/mediator systems are important bioremediation agents as the rates of reactions can be enhanced in the presence of the mediators. The decolorization mechanism of two triarylmethane dyes, namely, Basic Green 4 and Acid Violet 17 is reported using Cyathus bulleri laccase. Basic Green 4 was decolorized through N-demethylation by laccase alone, while in mediator assisted reactions, dye breakdown was initiated from oxidation of carbinol form of the dye. Benzaldehyde and N,N-dimethyl aniline were the major end products. With Acid Violet 17, laccase carried out N-deethylation and in mediator assisted reactions, oxidation of the carbinol form of the dye occurred resulting in formation of formyl benzene sulfonic acid, carboxy benzene sulfonic acid and benzene sulfonic acid. Toxicity analysis revealed that Basic Green 4 was toxic and treatment with laccase/mediators resulted in 80-100% detoxification. The treatment of the textile dye solution using laccase and 2,2'-azino-di-(-ethylbenzothiazoline-6-sulfonic acid) (ABTS) was demonstrated in an enzyme membrane reactor. At a hydraulic retention time of 6h, the process was operated for a period of 15 days with nearly 95% decolorization, 10% reduction in flux and 70% recovery of active ABTS. PMID:19539671

  6. Phenylazoindole dyes 3: Determination of azo-hydrazone tautomers of new phenylazoindole dyes in solution and solid state

    NASA Astrophysics Data System (ADS)

    Babür, Banu; Sefero?lu, Nurgül; Aktan, Ebru; Hökelek, Tuncer; ?ahin, Ertan; Sefero?lu, Zeynel

    2015-02-01

    A new two series of phenylazo indole dyes was synthesized and the structures of the dyes were confirmed by UV-vis, FT-IR, HRMS and 1H/13C NMR spectroscopic techniques. Five of these dyes (I, I?, II?, III and III?) were also characterized in solid state by using single crystal X-ray diffraction studies besides other spectroscopic techniques. The geometries of the azo and hydrazone tautomeric forms of the dyes were optimized by using Density Functional Theory (DFT). In addition, the effects of the donor and acceptor groups on the azo and hydrazone forms of the dyes were evaluated experimentally and theoretically. The results indicate that the phenylazoindole dyes derived from 2-phenyl indole as coupling component exist as azo form in solution, gas phase and solid state.

  7. Decolorization of Anthraquinonic Dyes from Textile Effluent Using Horseradish Peroxidase: Optimization and Kinetic Study

    PubMed Central

    Šekuljica, Nataša Ž.; Prlainovi?, Nevena Ž.; Stefanovi?, Andrea B.; Žuža, Milena G.; ?i?kari?, Dragana Z.; Mijin, Dušan Ž.; Kneževi?-Jugovi?, Zorica D.

    2015-01-01

    Two anthraquinonic dyes, C.I. Acid Blue 225 and C.I. Acid Violet 109, were used as models to explore the feasibility of using the horseradish peroxidase enzyme (HRP) in the practical decolorization of anthraquinonic dyes in wastewater. The influence of process parameters such as enzyme concentration, hydrogen peroxide concentration, temperature, dye concentration, and pH was examined. The pH and temperature activity profiles were similar for decolorization of both dyes. Under the optimal conditions, 94.7% of C.I. Acid Violet 109 from aqueous solution was decolorized (treatment time 15?min, enzyme concentration 0.15?IU/mL, hydrogen peroxide concentration 0.4?mM, dye concentration 30?mg/L, pH 4, and temperature 24°C) and 89.36% of C.I. Acid Blue 225 (32?min, enzyme concentration 0.15?IU/mL, hydrogen peroxide concentration 0.04?mM, dye concentration 30?mg/L, pH 5, and temperature 24°C). The mechanism of both reactions has been proven to follow the two substrate ping-pong mechanism with substrate inhibition, revealing the formation of a nonproductive or dead-end complex between dye and HRP or between H2O2 and the oxidized form of the enzyme. Both chemical oxygen demand and total organic carbon values showed that there was a reduction in toxicity after the enzymatic treatment. This study verifies the viability of use of horseradish peroxidase for the wastewaters treatment of similar anthraquinonic dyes. PMID:25685837

  8. crystals

    NASA Astrophysics Data System (ADS)

    Badalyan, A.; Hovsepyan, R.; Mantashyan, P.; Mekhitaryan, V.; Drampyan, R.

    2014-07-01

    A novel combined interferometric-mask method for the formation of micro- and nanometric scale three-dimensional (3D) rotational symmetry quasi-crystalline refractive lattice structures in photorefractive materials is demonstrated experimentally. The method is based on micrometric scale spatial modulation of the light by amplitude mask in the radial directions and along the azimuthal angle and the use of counter-propagating beam geometry building up Gaussian standing wave, which defines the light modulation in the axial direction with half-wavelength periodicity. 3D intensity pattern can be represented as numerous mask-generated 2D quasi-periodic structures located in each anti-node of the standing wave. The formed 3D intensity distributions of the optical beams can be imparted into the photorefractive medium thus creating the micro- and sub-micrometric scale 3D refractive index volume lattices. The used optical scheme allows also the formation of 2D lattices by removing the back-reflecting mirror. 2D and 3D refractive lattices were recorded with the use of 532 nm laser beam and rotational symmetry mask in doped lithium niobate crystals and were tested by the probe beam far-field diffraction pattern imaging and direct observation by phase microscope. The formed rotational symmetry 3D refractive structures have the periods of 20-60 ?m in the radial directions, 60 ?m along the azimuthal angle and half-wavelength 266 nm in the axial direction.

  9. ZnO nanowires array grown on Ga-doped ZnO single crystal for dye-sensitized solar cells

    PubMed Central

    Hu, Qichang; Li, Yafeng; Huang, Feng; Zhang, Zhaojun; Ding, Kai; Wei, Mingdeng; Lin, Zhang

    2015-01-01

    High quality ZnO nanowires arrays were homoepitaxial grown on Ga-doped ZnO single crystal (GZOSC), which have the advantages of high conductivity, high carrier mobility and high thermal stability. When it was employed as a photoanode in the DSSCs, the cell exhibited a 1.44% power-conversion efficiency under the illumination of one sun (AM 1.5G). The performance is superior to our ZnO nanowires/FTO based DSSCs under the same condition. This enhanced performance is mainly attributed to the perfect interface between the ZnO nanowires and the GZOSC substrate that contributes to lower carrier scattering and recombination rates compared with that grown on traditional FTO substrate. PMID:26099568

  10. ZnO nanowires array grown on Ga-doped ZnO single crystal for dye-sensitized solar cells.

    PubMed

    Hu, Qichang; Li, Yafeng; Huang, Feng; Zhang, Zhaojun; Ding, Kai; Wei, Mingdeng; Lin, Zhang

    2015-01-01

    High quality ZnO nanowires arrays were homoepitaxial grown on Ga-doped ZnO single crystal (GZOSC), which have the advantages of high conductivity, high carrier mobility and high thermal stability. When it was employed as a photoanode in the DSSCs, the cell exhibited a 1.44% power-conversion efficiency under the illumination of one sun (AM 1.5G). The performance is superior to our ZnO nanowires/FTO based DSSCs under the same condition. This enhanced performance is mainly attributed to the perfect interface between the ZnO nanowires and the GZOSC substrate that contributes to lower carrier scattering and recombination rates compared with that grown on traditional FTO substrate. PMID:26099568

  11. Peruvian natural dye plants

    Microsoft Academic Search

    Kay K. Antúnez de Mayolo

    1989-01-01

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

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

    Microsoft Academic Search

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

    2007-01-01

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

  13. [Anaphylaxis to blue dyes].

    PubMed

    Langner-Viviani, F; Chappuis, S; Bergmann, M M; Ribi, C

    2014-04-16

    In medicine, vital blue dyes are mainly used for the evaluation of sentinel lymph nodes in oncologic surgery. Perioperative anaphylaxis to blue dyes is a rare but significant complication. Allergic reactions to blue dyes are supposedly IgE-mediated and mainly caused by triarylmethanes (patent blue and isosulfane blue) and less frequently by methylene blue. These substances usually do not feature on the anesthesia record and should not be omitted from the list of suspects having caused the perioperative reaction, in the same manner as latex and chlorhexidine. The diagnosis of hypersensitivity to vital blue dyes can be established by skin test. We illustrate this topic with three clinical cases. PMID:24834647

  14. Dyeing Wool with Fungi

    NSDL National Science Digital Library

    Sue Assinder

    2002-01-01

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

  15. Tetrazolium Violet Induced Apoptosis and Cell Cycle Arrest in Human Lung Cancer A549 Cells

    PubMed Central

    Zhang, Xiao-Hong; Zhang, Nan; Lu, Jian-Mei; Kong, Qing-Zhong; Zhao, Yun-Feng

    2012-01-01

    Tetrazolium violet is a tetrazolium salt and has been proposed as an antitumor agent. In this study, we reported for the first time that tetrazolium violet not only inhibited human lung cancer A549 cell proliferation but also induced apoptosis and blocked cell cycle progression in the G1 phase. The results showed that tetrazolium violet significantly decreased the viability of A549 cells at 5-15 ?M. Tetrazolium violet -induced apoptosis in A549 cells was confirmed by H33258 staining assay. In A549, tetrazolium violet blocked the progression of the cell cycle at G1 phase by inducing p53 expression and further up-regulating p21/WAF1 expression. In addition, an enhancement in Fas/APO-1 and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), as well as caspase, were responsible for the apoptotic effect induced by tetrazolium violet. The conclusion of this study is that tetrazolium violet induced p53 expression which caused cell cycle arrest and apoptosis. These findings suggest that tetrazolium violet has strong potential for development as an agent for treatment lung cancer. PMID:24116292

  16. 75 FR 25209 - Carbazole Violet Pigment 23 from India: Rescission of Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-07

    ...Administration A-533-838 Carbazole Violet Pigment 23 from India: Rescission of Administrative...antidumping duty order on carbazole violet pigment 23 (CVP 23) from India for the period...initiated the review with respect to Meghmani Pigments (Meghmani) based on its request...

  17. 75 FR 34699 - Carbazole Violet Pigment 23 from India: Rescission of Countervailing Duty Administrative Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ...Administration [C-533-839] Carbazole Violet Pigment 23 from India: Rescission of Countervailing...countervailing duty order on Carbazole Violet Pigment 23(CVP-23) from India. See Antidumping...we received a request from Meghmani Pigments requesting an administrative review...

  18. DISPOSITIF DE MESURE DES TEMPRATURES AU FOUR SOLAIRE PAR PYROMTRIE DANS L'ULTRA-VIOLET

    E-print Network

    Paris-Sud XI, Université de

    des fours solaires présente quelques difficultés par suite de la réflexion d'une partie du rayonnement fonctionnant dans l'ultra-violet (filtre interférentiel), cependant que le rayonnement solaire incident est. D'autre part, c'est dans le domaine de l'ultra-violet que le rayonnement solaire se différencie le

  19. Oxazine laser dyes

    DOEpatents

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

    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##

  20. Tie-Dye Chemistry

    NSDL National Science Digital Library

    Gretchen Cessna

    2001-03-01

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

  1. 75 FR 10759 - Carbazole Violet Pigment 23 from India: Initiation of Antidumping Duty Changed-Circumstances Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-09

    ...Administration [A-533-838] Carbazole Violet Pigment 23 from India: Initiation of Antidumping...antidumping duty order on carbazole violet pigment 23 from India with respect to Meghmani Pigments. EFFECTIVE DATE: March 9, 2010. FOR...

  2. Monolithic dye laser amplifier

    DOEpatents

    Kuklo, T.C.

    1993-03-30

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

  3. Monolithic dye laser amplifier

    DOEpatents

    Kuklo, Thomas C. (Ripon, CA)

    1993-01-01

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

  4. Transient transfection of mammalian cells using a violet diode laser

    NASA Astrophysics Data System (ADS)

    Torres-Mapa, Maria Leilani; Angus, Liselotte; Ploschner, Martin; Dholakia, Kishan; Gunn-Moore, Frank J.

    2010-07-01

    We demonstrate the first use of the violet diode laser for transient mammalian cell transfection. In contrast to previous studies, which showed the generation of stable cell lines over a few weeks, we develop a methodology to transiently transfect cells with an efficiency of up to ~40%. Chinese hamster ovary (CHO-K1) and human embryonic kidney (HEK293) cells are exposed to a tightly focused 405-nm laser in the presence of plasmid DNA encoding for a mitochondrial targeted red fluorescent protein. We report transfection efficiencies as a function of laser power and exposure time for our system. We also show, for the first time, that a continuous wave laser source can be successfully applied to selective gene silencing experiments using small interfering RNA. This work is a major step towards an inexpensive and portable phototransfection system.

  5. Chromonic liquid crystalline properties of dyes

    NASA Astrophysics Data System (ADS)

    Yao, Xuxia; Park, Jung; Srinivasarao, Mohan

    2009-03-01

    As a new class of lyotropic liquid crystals, chromonic liquid crystals (CLCs) can self-assemble into an ordered complex fluid, potentially useful for organic solar cells. Different from common amphiphilic lyotropic mesophases, CLCs have no optimum aggregation size, which implies the order parameter increases with concentration. We used capillary flow and magnetic field to induce alignment in chromonic dyes and studied the aggregation behavior by Vis-spectroscopy, the phase behavior by POM and DSC, and the order distribution by Raman Scattering. We also investigated how the molecular structures influence the structures of mesogens and the morphology in the dried film which will further influence the charge mobility in the solar cells.

  6. 75 FR 36630 - Carbazole Violet Pigment 23 from the People's Republic of China: Final Results of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-28

    ...Administration A-570-892 Carbazole Violet Pigment 23 from the People's Republic of China...antidumping duty order on carbazole violet pigment 23 (CVP 23) from the People's Republic of China (PRC). See Carbazole Violet Pigment 23 From the People's Republic of...

  7. 77 FR 1463 - Carbazole Violet Pigment 23 From the People's Republic of China: Final Rescission of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-10

    ...Administration [A-570-892] Carbazole Violet Pigment 23 From the People's Republic of China...antidumping duty order on carbazole violet pigment 23 (CVP-23) from the People's Republic...1\\ See Carbazole Violet Pigment 23 From the People's Republic of...

  8. 76 FR 55003 - Carbazole Violet Pigment 23 From the People's Republic of China: Preliminary Intent To Rescind...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ...Administration [A-570-892] Carbazole Violet Pigment 23 From the People's Republic of China...antidumping duty order on carbazole violet pigment 23 (CVP 23) from the People's Republic...Antidumping Duty Order: Carbazole Violet Pigment 23 From the People's Republic of...

  9. 75 FR 12497 - Carbazole Violet Pigment 23 from India and the People's Republic of China: Final Results of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ...A-533-838, A-570-892] Carbazole Violet Pigment 23 from India and the People's Republic...antidumping duty orders on carbazole violet pigment 23 (CVP 23) from India and the People's...Antidumping Duty Order: Carbazole Violet Pigment 23 From the People's Republic of...

  10. 75 FR 25840 - Carbazole Violet Pigment 23 from the People's Republic of China: Extension of Time Limit for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-10

    ...Administration [A-570-892] Carbazole Violet Pigment 23 from the People's Republic of China...antidumping duty order on carbazole violet pigment 23 (CVP 23) from the People's Republic...November 30, 2008. See Carbazole Violet Pigment 23 From the People's Republic of...

  11. 75 FR 29718 - Carbazole Violet Pigment 23 From India and the People's Republic of China: Continuation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-27

    ...A-533-838, A-570-892] Carbazole Violet Pigment 23 From India and the People's Republic...antidumping duty orders on carbazole violet pigment 23 (CVP-23) from India and the People's...2, 2009); See also Carbazole Violet Pigment 23 From China and India, 74 FR...

  12. Characteristics of dye-sensitized solar cells using natural dye

    Microsoft Academic Search

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

    2009-01-01

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

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

    Microsoft Academic Search

    Keith R. Millington; Keith W. Fincher; A. Lee King

    2007-01-01

    Many mordant dyes commonly used in the textile industry form coordination complexes at the surface of nanocrystalline TiO2. 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

  14. Dye system for dye laser applications

    DOEpatents

    Hammond, Peter R. (Livermore, CA)

    1991-01-01

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

  15. A high-peak-power UV picosecond-pulse light source based on a gain-switched 1.55 microm laser diode and its application to time-resolved spectroscopy of blue-violet materials.

    PubMed

    Sato, Aya; Kono, Shunsuke; Saito, Kyosuke; Sato, Ki-ichi; Yokoyama, Hiroyuki

    2010-02-01

    We generated sub-kilowatt peak-power and 6-ps duration 390-nm optical pulses via the fourth harmonic generation of amplified optical output from a gain-switched 1.55-microm laser diode. We obtained a power-conversion-efficiency of 12% from 1.55-microm to 390-nm light, and subsequently applied the ultraviolet pulses to time-resolved spectroscopy of blue-violet luminescent materials, including a Coumarine dye solution and nitride semiconductor materials using single-photon and two-photon excitation schemes. PMID:20174080

  16. Photonic band-gap effects upon the light emission from a dye-polymer-opal composite

    Microsoft Academic Search

    S. G. Romanov; T. Maka; C. M. Sotomayor Torres; M. Müller; R. Zentel

    1999-01-01

    A polymeric photonic crystal formed by impregnating an opal with a Coumarin 6 dye containing polymer has been prepared and its emission properties studied by angular-resolved photoluminescence. A strong spectral redistribution of the luminescence intensity was observed in the dye-polymer-opal compared to that of the dye-polymer reference sample. The emission spectrum shows a marked distortion compared with the reference sample,

  17. Photonic band-gap effects upon the light emission from a dye–polymer–opal composite

    Microsoft Academic Search

    S. G. Romanov; T. Maka; C. M. Sotomayor Torres; R. Zentel

    1999-01-01

    A polymeric photonic crystal formed by impregnating an opal with a Coumarin 6 dye containing polymer has been prepared and its emission properties studied by angular-resolved photoluminescence. A strong spectral redistribution of the luminescence intensity was observed in the dye-polymer-opal compared to that of the dye-polymer reference sample. The emission spectrum shows a marked distortion compared with the reference sample,

  18. Comparison of violet versus red laser exposures on visual search performance in humans.

    PubMed

    Previc, Fred H; McLin, Leon N; Novar, Brenda J; Kosnik, William

    2005-01-01

    Previous research suggests that the visual impairment of a violet laser is not highly localized on the retina, because the lens absorbs most short-wavelength visible light and partly retransmits it as a diffuse fluorescence at approximately 500 nm. The present study investigated whether a 405 nm violet diode laser more greatly impairs visual search performance in humans than does a 670 nm red diode laser, depending on target eccentricity. Participants had to locate a square among 15 diamonds spread throughout a visual search display while being exposed to a violet or red laser beam that was either continuous or flickering and presented either on-axis or 33 degrees off-axis. Whereas the continuous on-axis violet and red lasers had comparable effects on search performance when the target was located near the center of the beam, the violet laser disrupted processing of eccentric targets more than did the red laser. The search decrements were reduced for both lasers when the beams were flickered or presented off-axis. Both the bluish appearance and greater spatial spread of effect of the violet laser suggest that the unique impairment caused by a violet laser beam derives from its induced lens fluorescence. PMID:16229647

  19. Trityl dyes patent blue V and brilliant blue G - clinical relevance and in vitro analysis of the function of the outer blood-retinal barrier.

    PubMed

    Mennel, Stefan; Meyer, Carsten H; Schmidt, Jörg C; Kaempf, Stefanie; Thumann, Gabriele

    2008-01-01

    The use of vital dyes during vitrectomy allows easier removal of less recognizable structures like epiretinal membranes or the internal limiting membrane (ILM). In recent years, numerous studies have investigated the use of indocyanine green (ICG), trypan blue (Membrane Blue), triamcinolone, autologous blood and presently trityl dyes such as patent blue V (PBV, Blueron), crystal violet and brilliant blue G (BBG, Brilliant Peel) in chromovitrectomy. Reports on potential risks of these dyes, especially ICG, such as reduced visual acuity, possible visual field defects or alterations of the retinal pigment epithelium (RPE) limited their application. A systematic review of the literature up to July 2007 was performed using Medline (http://www.ncbi.nlm.nih.gov/ PubMed/) where we specifically searched for relevant information regarding the laboratory as well as clinical use of PB and BBG. To evaluate the effect of PB and BBG on the RPE, PB and BBG have been added to an in vitro model of the outer blood-retinal barrier to assess dye-associated barrier properties. Two concentrations of PB (2.4 and 1.2 mg/ml) and BBG (0.25 and 2.4 mg/ml) were investigated. To simulate in vivo conditions of a fluid-filled eye and an air-filled eye the dyes were added either to the culture medium or directly to the RPE cells where they remained for 2.5 min. To determine barrier properties, transepithelial resistance (TER) was measured at 3 days of follow-up. Ultrastructural integrity of RPE cells was evaluated by transmission electron microscopy. Following application of PB, barrier properties in the fluid- as well as in the air-filled eye showed only mild, transient and no significant decrease in TER. BBG did not cause a breakdown of the outer bloodretinal barrier at the concentration of 0.25 mg/ml in the model of the fluid-filled eye. The concentration of 2.4 mg/ml in the model of the fluid-filled eye as well as both concentrations in the model of the air-filled eye showed a minor decrease after 1.5 h, which was no longer observed after 24 h. Transmission electron microscopy did not show any dye-associated ultrastructural alterations to the RPE cells. In clinical use, PB showed only mild staining of epiretinal membranes and moderate staining of the ILM. Although BBG did not stain epiretinal membranes, it represents an appropriate candidate for the future, as BBG has a high affinity for the ILM. The use of trityl dyes in the posterior eye segment seems to be safe concerning damage to the RPE and its barrier function, especially when the dye is applied to the fluid-filled eye. PMID:18535384

  20. Azo Dye Biodecolorization Enhanced by Echinodontium taxodii Cultured with Lignin

    PubMed Central

    Meng, Jing; Yu, Hongbo; Zhang, Xiaoyu

    2014-01-01

    Lignocellulose facilitates the fungal oxidization of recalcitrant organic pollutants through the extracellular ligninolytic enzymes induced by lignin in wood or other plant tissues. However, available information on this phenomenon is insufficient. Free radical chain reactions during lignin metabolism are important in xenobiotic removal. Thus, the effect of lignin on azo dye decolorization in vivo by Echinodontium taxodii was evaluated. In the presence of lignin, optimum decolorization percentages for Remazol Brilliant Violet 5R, Direct Red 5B, Direct Black 38, and Direct Black 22 were 91.75% (control, 65.96%), 76.89% (control, 43.78%), 43.44% (control, 17.02%), and 44.75% (control, 12.16%), respectively, in the submerged cultures. Laccase was the most important enzyme during biodecolorization. Aside from the stimulating of laccase activity, lignin might be degraded by E. taxodii, and then these degraded low-molecular-weight metabolites could act as redox mediators promoting decolorization of azo dyes. The relationship between laccase and lignin degradation was investigated through decolorization tests in vitro with purified enzyme and dozens of aromatics, which can be derivatives of lignin and can function as laccase mediators or inducers. Dyes were decolorized at triple or even higher rates in certain laccase–aromatic systems at chemical concentrations as low as 10 µM. PMID:25285777

  1. 45.4 / V. Chigrinov 45.4: Azo-Dye Alignment for Displays and Photonics

    E-print Network

    of voltage holding ratio (VHR) for the photo-aligned LC cell (>99% at 800 C) and residual DC voltage (45.4 / V. Chigrinov 45.4: Azo-Dye Alignment for Displays and Photonics Vladimir Chigrinov and Hoi Incorporated, Japan Abstract Liquid crystal photo-alignment using azo-dyes for display and photonics

  2. Electron Injection at Dye-Sensitized Semiconductor Electrodes

    NASA Astrophysics Data System (ADS)

    Watson, David F.; Meyer, Gerald J.

    2005-05-01

    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.

  3. Ingrid Violet pouse Lacroix ne le 5 mai 1979, marie, 1 enfant

    E-print Network

    Violet, Ingrid

    Paul Painlevé, UMR 8524 Université Lille 1 T 03 20 43 66 31 B ingrid.violet@univ-lille1.fr Í http://math.univ-lille1.fr/ violet/ Position actuelle Depuis oct. 2007 Maître de conférence, Université Lille 1, Lille. Laboratoire Paul Painlevé, UMR CNRS 8524. Membre de léquipe projet SIMPAF, Inria Lille Nord-Europe.. Cursus

  4. Blue-violet photoluminescence from large-scale highly aligned boron carbonitride nanofibers

    Microsoft Academic Search

    X. D. Bai; E. G. Wang; J. Yu; Hui Yang

    2000-01-01

    We report on the strong blue-violet photoluminescence (PL) at room temperature from the large-scale highly aligned boron carbonitride (BCN) nanofibers synthesized by bias-assisted hot filament chemical vapor deposition. The photoluminescence peak wavelength shifts in the range of 470-390 nm by changing the chemical composition of the BCN nanofibers, which shows an interesting blue and violet-light-emitting material with adjustable optical properties.

  5. Blue–violet photoluminescence from large-scale highly aligned boron carbonitride nanofibers

    Microsoft Academic Search

    X. D. Bai; E. G. Wang; J. Yu; Hui Yang

    2000-01-01

    We report on the strong blue–violet photoluminescence (PL) at room temperature from the large-scale highly aligned boron carbonitride (BCN) nanofibers synthesized by bias-assisted hot filament chemical vapor deposition. The photoluminescence peak wavelength shifts in the range of 470–390 nm by changing the chemical composition of the BCN nanofibers, which shows an interesting blue and violet-light-emitting material with adjustable optical properties.

  6. Electron Spin Resonance Investigations of Ultra-violet and X-irradiated Methionine

    Microsoft Academic Search

    H. Mönig; R. Koch

    1964-01-01

    WE have already reported1 that both ultra-violet and X-rays produce the same electron spin resonance signal in cysteine but that in certain other sulphur-containing compounds2 the two types of radiation produce electron spin resonance signals which are not identical. On exposing bovine serum albumin, homocysteine and methio-nine to ultra-violet following irradiation with X-rays the X-ray signal was transformed. This change

  7. Photoinduced ordering and anchoring properties of azo-dye films.

    PubMed

    Kiselev, Alexei D; Chigrinov, Vladimir; Huang, Dan Ding

    2005-12-01

    We study both theoretically and experimentally the anchoring properties of photoaligning azo-dye films in contact with a nematic liquid crystal depending on the photoinduced ordering of azo-dye molecules. In the mean field approximation, we found that the bare surface anchoring energy depends linearly on the azo-dye order parameter and the azimuthal anchoring strength decays to zero in the limit of vanishing photoinduced ordering. From the absorption dichroism spectra measured in azo-dye films that are prepared from an azo-dye derivative with polymerizable terminal groups we obtain the dependence of the dichroic ratio on the irradiation dose. We also measure the polar and azimuthal anchoring strengths in nematic liquid crystal (NLC) cells aligned by the azo-dye films and derive the anchoring strengths as functions of the dichroic ratio, which is proportional to the photoinduced order parameter. Although linear fitting of the experimental data for both anchoring strengths gives reasonable results, it, predicts vanishing of the azimuthal anchoring strength at some nonzero value of the azo-dye order parameter, in contradiction with theory. By using a simple phenomenological model we show that this discrepancy can be attributed to the difference between the surface and bulk order parameters in the films. The measured polar anchoring energy is found to be an order of magnitude higher than the azimuthal strength. Our theory suggests that the quadrupole term of the spherical harmonics expansion for the azo-dye-NLC intermolecular potential might be of importance for the understanding of this difference. PMID:16485960

  8. High efficient photonic band-edge cholesteric liquid crystal lasers

    Microsoft Academic Search

    Ying Zhou; Yuhua Huang; Zhibing Ge; Shin-Tson Wu

    2007-01-01

    In this paper, we demonstrated a new dye-doped cholesteric liquid crystal (CLC) photonic band edge laser with emission enhanced by an external cholesteric resonator. As one-dimensional photonic crystal, the 5-mum dye-doped cholesteric liquid crystal cell generates circularly polarized laser emission at its photonic band edge. When sandwiched between two 5-mum cholesteric liquid crystal mirrors whose reflection band reflects the laser

  9. New perylene derivative dyes for dye-sensitized solar cells

    Microsoft Academic Search

    Ceylan Zafer; Mahmut Kus; Gulsah Turkmen; Haluk Dincalp; Serafettin Demic; Baha Kuban; Yildirim Teoman; Siddik Icli

    2007-01-01

    We have studied the influence of the spacer alkyl chain length of perylenemonoimide (PMI) dyes on the device performance in dye-sensitized solar cells (DSSCs). We observed that the dyes with longer and brunched alkyl chains exhibit higher efficiencies in DSSCs. In line with these statements we now report the highest efficiency obtained under standard conditions for a perylene imide derivative

  10. Anthraquinone dyes as photosensitizers for dye-sensitized solar cells

    Microsoft Academic Search

    Chaoyan Li; Xichuan Yang; Ruikui Chen; Jingxi Pan; Haining Tian; Hongjun Zhu; Xiuna Wang; Anders Hagfeldt; Licheng Sun

    2007-01-01

    Three anthraquinone dyes with carboxylic acid as anchoring group are designed and synthesized as sensitizers for dye-sensitized solar cells (DSSCs). Preliminary photophysical and photoelectrochemical measurements show that these anthraquinone dyes have very low performance on DSSC applications, although they have broad and intense absorption spectra in the visible region (up to 800nm). Transient absorption kinetics, fluorescence lifetime measurements and density

  11. Dye Removal from Textile Dye Wastewater Using Recycled Alum Sludge

    Microsoft Academic Search

    W Chu

    2001-01-01

    The removal of dyes from textile dying wastewater by recycled alum sludge (RAS) generated by the coagulation process itself was studied and optimized. One hydrophobic and one hydrophilic dye were used as probes to examine the performance of this process. It was found that RAS is a good way of removing hydrophobic dye in wastewater, while simultaneously reducing the fresh

  12. Use of cellulose-based wastes for adsorption of dyes from aqueous solutions.

    PubMed

    Annadurai, Gurusamy; Juang, Ruey-Shin; Lee, Duu-Jong

    2002-06-10

    Low-cost banana and orange peels were prepared as adsorbents for the adsorption of dyes from aqueous solutions. Dye concentration and pH were varied. The adsorption capacities for both peels decreased in the order methyl orange (MO) > methylene blue (MB) > Rhodamine B (RB) > Congo red (CR) > methyl violet (MV) > amido black 10B (AB). The isotherm data could be well described by the Freundlich and Langmuir equations in the concentration range of 10-120 mg/l. An alkaline pH was favorable for the adsorption of dyes. Based on the adsorption capacity, it was shown that banana peel was more effective than orange peel. Kinetic parameters of adsorption such as the Langergren rate constant and the intraparticle diffusion rate constant were determined. For the present adsorption process intraparticle diffusion of dyes within the particle was identified to be rate limiting. Both peel wastes were shown to be promising materials for adsorption removal of dyes from aqueous solutions. PMID:12031611

  13. Water soluble laser dyes

    DOEpatents

    Hammond, Peter R. (Livermore, CA); Feeman, James F. (Wyomissing, PA); Field, George F. (Santa Ana, CA)

    1998-01-01

    Novel water soluble dyes of the formula I are provided ##STR1## wherein R.sup.1 and R.sup.4 are alkyl of 1 to 4 carbon atoms or hydrogen; or R.sup.1 -R.sup.2 or R.sup.2 -R.sup.4 form part of aliphatic heterocyclic rings; R.sup.2 is hydrogen or joined with R.sup.1 or R.sup.4 as described above; R.sup.3 is --(CH.sub.2).sub.m --SO.sub.3.sup.-, where m is 1 to 6; X is N, CH or ##STR2## where Y is 2 --SO.sub.3.sup.- ; Z is 3, 4, 5 or 6 --SO.sub.3.sup.-. The novel dyes are particularly useful as the active media in water solution dye lasers.

  14. Hair cosmetics: dyes.

    PubMed

    Guerra-Tapia, A; Gonzalez-Guerra, E

    2014-11-01

    Hair plays a significant role in body image, and its appearance can be changed relatively easily without resort to surgical procedures. Cosmetics and techniques have therefore been used to change hair appearance since time immemorial. The cosmetics industry has developed efficient products that can be used on healthy hair or act on concomitant diseases of the hair and scalp. Dyes embellish the hair by bleaching or coloring it briefly, for temporary periods of longer duration, or permanently, depending on the composition of a dye (oxidative or nonoxidative) and its degree of penetration of the hair shaft. The dermatologist's knowledge of dyes, their use, and their possible side effects (contact eczema, cancer, increased porosity, brittleness) can extend to an understanding of cosmetic resources that also treat hair and scalp conditions. PMID:24656996

  15. Water soluble laser dyes

    DOEpatents

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

    1998-08-11

    Novel water soluble dyes of the formula 1 are provided by the formula described in the paper wherein R{sup 1} and R{sup 4} are alkyl of 1 to 4 carbon atoms or hydrogen; or R{sup 1}--R{sup 2} or R{sup 2}--R{sup 4} form part of aliphatic heterocyclic rings; R{sup 2} is hydrogen or joined with R{sup 1} or R{sup 4} as described above; R{sup 3} is --(CH{sub 2}){sub m}--SO{sub 3}{sup {minus}}, where m is 1 to 6; X is N, CH or formula 2 given in paper where Y is 2 --SO{sub 3}{sup {minus}} ; Z is 3, 4, 5 or 6 --SO{sub 3}{sup {minus}}. The novel dyes are particularly useful as the active media in water solution dye lasers.

  16. Investigation of ultra violet (UV) resistance for high strength fibers

    NASA Astrophysics Data System (ADS)

    Said, M. A.; Dingwall, Brenda; Gupta, A.; Seyam, A. M.; Mock, G.; Theyson, T.

    Ultra long duration balloons (ULDB), currently under development by the National Aeronautics and Space Administration (NASA), requires the use of high strength fibers in the selected super-pressure pumpkin design. The pumpkin shape balloon concept allows clear separation of the load transferring functions of the major structural elements of the pneumatic envelope, the tendons and the film. Essentially, the film provides the gas barrier and transfers only local pressure load to the tendons. The tendons, in the mean time, provide the global pressure containing strength. In that manner, the strength requirement for the film only depends on local parameters. The tendon is made of p-phenylene-2,6-benzobisoxazole (PBO) fibers, which is selected due to its high strength to weight ratio when compared to other high performance, commercially available, fibers. High strength fibers, however, are known to degrade upon exposure to light, particularly at short wavelengths. This paper reports the results of an investigation of the resistance of four commercial high strength fibers to ultra violet (UV) exposure. The results indicate that exposing high strength fibers in continuous yarn form to UV led to serious loss in strength of the fibers except for Spectra® fibers. The adverse changes in mechanical behavior occurred over short duration of exposure compared to the 100 day duration targeted for these missions. UV blocking finishes to improve the UV resistance of these fibers are being investigated. The application of these specially formulated coatings is expected to lead to significant improvement of the UV resistance of these high performance fibers. In this publication, we report on the mechanical behavior of the fibers pre- and post-exposure to UV, but without application of the blocking finishes.

  17. Synthesis of interpenetrating network hydrogel from poly(acrylic acid-co-hydroxyethyl methacrylate) and sodium alginate: modeling and kinetics study for removal of synthetic dyes from water.

    PubMed

    Mandal, Bidyadhar; Ray, Samit Kumar

    2013-10-15

    Several interpenetrating network (IPN) hydrogels were made by free radical in situ crosslink copolymerization of acrylic acid (AA) and hydroxy ethyl methacrylate in aqueous solution of sodium alginate. N,N'-methylenebisacrylamide (MBA) was used as comonomer crosslinker for making these crosslink hydrogels. All of these hydrogels were characterized by carboxylic content, FTIR, SEM, XRD, DTA-TGA and mechanical properties. Swelling, diffusion and network parameters of the hydrogels were studied. These hydrogels were used for adsorption of two important synthetic dyes, i.e. Congo red and methyl violet from water. Isotherms, kinetics and thermodynamics of dye adsorption by these hydrogels were also studied. PMID:23987343

  18. Tunable ultraviolet solid-state dye laser based on MPMMA doped with pyrromethene 597

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Fan, R. W.; Xia, Y. Q.; Chen, D. Y.

    2011-01-01

    Solid-state dye sample based on modified polymethyl methacrylate (MPMMA) co-doped with pyrromethene 597 (PM597), and coumarin 460 (C460) were prepared. A frequency-doubled pulsed Nd:YAG laser is used to pump solid-state dye sample, and the narrow linewidth dye laser of 94.4 mJ was obtained at 582 nm in an oscillator-amplifier configuration. Using a beta-BaB2O4 (BBO) crystal to frequency double the dye laser into ultraviolet (UV), a tuning range from 279 to 305 nm was demonstrated from a single doped PM597 dye. To the best of our knowledge, the UV tuning range is the best under the same condition so far. The conversion slope efficiency from solid dye laser to UV laser was 8.9% and the highest UV laser output energy reached 6.94 mJ at 291 nm.

  19. Dye filled security seal

    DOEpatents

    Wilson, Dennis C. W. (Tijeras, NM)

    1982-04-27

    A security seal for providing an indication of unauthorized access to a sealed object includes an elongate member to be entwined in the object such that access is denied unless the member is removed. The elongate member has a hollow, pressurizable chamber extending throughout its length that is filled with a permanent dye under greater than atmospheric pressure. Attempts to cut the member and weld it together are revealed when dye flows through a rupture in the chamber wall and stains the outside surface of the member.

  20. Culture of the green microalga Botryococcus braunii Showa with LED irradiation eliminating violet light enhances hydrocarbon production and recovery.

    PubMed

    Atobe, Sueko; Saga, Kiyotaka; Maeyama, Haruko; Fujiwara, Kazuhiro; Okada, Shigeru; Imou, Kenji

    2014-10-01

    The green microalga Botryococcus braunii (B. braunii), race B, was cultured under light-emitting diode (LED) irradiation with and without violet light. This study examined the effect of violet light on hydrocarbon recovery and production in B. braunii. C34 botryococcene hydrocarbons were efficiently extracted by thermal pretreatments at lower temperatures when the alga was cultured without violet light. The hydrocarbon content was also higher (approximately 3%) in samples cultured without violet light. To elucidate the mechanism of effective hydrocarbon recovery and production, we examined structural components of the extracellular matrix (ECM). The amounts of extracellular carotenoids and water-soluble polymers extracted by thermal pretreatment from the ECM were decreased when the alga was cultured without violet light. These results indicate that LED irradiation without violet light is more effective for hydrocarbon recovery and production in B. braunii. Furthermore, structural ECM components are closely involved in hydrocarbon recovery and production in B. braunii. PMID:25069809

  1. Visible light assisted degradation of organic dye using Ag3PO4

    NASA Astrophysics Data System (ADS)

    Dhanabal, R.; Velmathi, S.; Bose, A. Chandra

    2015-06-01

    The study of visible light photodegradation of organic dye Methylene Blue (MB) have been investigated using silver phosphate (Ag3PO4) as a photocatalyst which is good efficient material for photocatalytic reaction. The simple ion-exchange method is used to prepare Ag3PO4. The structure of the material have been confirmed using X-ray diffraction which shows cubic structure of Ag3PO4. The functional group of the Ag3PO4 has been verified by Fourier transform infrared spectroscopy. The bandgap of Ag3PO4 is calculated using kubelka-munk function from the ultra violet-visible diffuse reflectance spectroscopy, the absorption of Ag3PO4 starts from 470 nm. Under simulated visible light irradiation, Ag3PO4 catalyst exhibits good catalytic ability for degrading MB dye.

  2. Decolorization and biodegradation of reactive blue 220 textile dye by Lentinus crinitus extracellular extract.

    PubMed

    Niebisch, Carolina Heyse; Malinowski, Alexandre Knoll; Schadeck, Ruth; Mitchell, David A; Kava-Cordeiro, Vanessa; Paba, Jaime

    2010-08-15

    Studies were carried on the decolorization of the textile dye reactive blue 220 (RB220) by a novel isolate of Lentinus crinitus fungi. The optimal conditions for the production of destaining activity were obtained in media containing intermediate concentrations of ammonium oxalate and glucose (10 g L(-1)) as nitrogen and carbon sources, respectively, at 28 degrees C and pH 5.5. Maximum decolorization efficiency against RB220 achieved in this study was around 95%. Ultra-violet and visible (UV-vis) spectrophotometric analyses, before and after decolorization, suggest that decolorization was due to biodegradation. This effect was associated with a putative low molecular weight laccase (41 kDa) displaying good tolerance to a wide range of pH values, salt concentrations and temperatures, suggesting a potential role for this organism in the remediation of real dye containing effluents. PMID:20452721

  3. Mutagenicity of textile dye products.

    PubMed

    Schneider, Klaus; Hafner, Christoph; Jäger, Ismene

    2004-01-01

    Within an EU-funded research project, 281 textile dye products in use at nine textile finishing companies from eight European countries were assessed for potential mutagenic properties. Most of the dyes belonged to the so-called existing substances. Data sources considered were data published in the literature, unpublished industrial data provided by dye producing companies, and laboratory testing. Data on mutagenicity are virtually absent for many of the dyes. Unpublished test results performed on behalf of the dye manufacturing industry proved to be an important data source that is not accessible under usual circumstances. Four dye stuffs contained in seven dye products in use at the textile finishing companies were judged to be mutagenic, based on published data from the literature. Mutagenicity testing using Salmonella typhimurium, strains TA98 and TA100, revealed positive results for about 28% (15 out of 53) of the dye products investigated. Upon further testing with the mouse lymphoma assay (L5178Y/TK(+/-)) 67% (6 out of 9) of Ames-positive dyes proved to be mutagenic in this mammalian cell test. All data sources combined led to an overall assessment of 14 dye products out of 281 being mutagenic. For 16 there is a suspicion of mutagenicity due to positive responses in one test but 71 of the dye products are without any data on mutagenicity. This paper describes the data aggregation process, evaluation criteria and the overall assessment, and exemplifies controversial evaluations. PMID:15052602

  4. Dye-modified nanochannel materials for photoelectronic and optical devices.

    PubMed

    Calzaferri, Gion; Li, Huanrong; Brühwiler, Dominik

    2008-01-01

    Artificial photonic antenna systems have been realised by incorporating organic dyes into zeolite L. The size and aspect ratio of the cylindrically shaped zeolite crystals can be tuned over a wide range, adding to the versatility of this host material. A 600 nm sized crystal, for example, consists of about 96 000 one-dimensional channels oriented parallel to the cylinder axis. Geometrical constraints imposed by the host structure lead to supramolecular organisation of the guests, allowing high concentrations of non- or only very weakly interacting dye molecules. A special twist is added to these systems by plugging the channel openings with a second type of fluorescent dye, a so-called stopcock molecule. The two types of molecules are precisely tuned to each other; the stopcocks are able to accept excitation energy from the dyes in the channels, but cannot pass it back. The supramolecular organisation of dyes in the zeolite channels corresponds to a first stage of organisation, allowing light-harvesting within the volume of a cylindrical crystal and radiationless energy transport to either the cylinder ends or centre. The second stage of organisation represents the coupling to an external acceptor or donor stopcock fluorophore at the channel entrances, which can then trap or inject electronic excitation energy. The third stage of organisation is realised by interfacing the material to an external device through a stopcock intermediate. We observed that electronic-excitation-energy transfer in dye-zeolite L materials occurs mainly along the channel axis and we have shown that macroscopically organised materials can be prepared. The new materials offer unique possibilities as building blocks for optical, electro-optical and sensing devices. PMID:18626875

  5. Comparison of violet diode laser with CO II laser in surgical performance of soft tissues

    NASA Astrophysics Data System (ADS)

    Hatayama, H.; Kato, J.; Inoue, A.; Akashi, G.; Hirai, Y.

    2007-02-01

    The violet diode laser (405nm) has recently begun to be studied for surgical use and authors reported the soft tissue could be effectively incised by irradiation power of even less than 1W. The wavelength of this laser is highly absorbed by hemoglobin, myoglobin or melanin pigment. Cutting or ablating soft tissues by lower irradiation power might be preferable for wound healing. The CO II laser is known to be preferable for low invasive treatment of soft tissues and widely used. The CO II laser light (10.6?m) is highly absorbed by water and proper for effective ablation of soft tissues. In this paper, we report the comparison of the violet diode laser with the CO II laser in surgical performance of soft tissues. Tuna tissue was used as an experimental sample. In the case of the violet diode laser, extensive vaporization of tissue was observed after the expansion of coagulation. Carbonization of tissue was observed after the explosion. On the other hand, consecutive vaporization and carbonization were observed immediately after irradiation in the case of CO II laser. The violet diode laser could ablate tissue equivalently with the CO II laser and coagulate larger area than the CO II laser. Therefore the violet diode laser might be expectable as a surgical tool which has excellent hemostatis.

  6. Kinetics and thermodynamics of textile dye adsorption from aqueous solutions using babassu coconut mesocarp.

    PubMed

    Vieira, Adriana P; Santana, Sirlane A A; Bezerra, Cícero W B; Silva, Hildo A S; Chaves, José A P; de Melo, Júlio C P; da Silva Filho, Edson C; Airoldi, Claudio

    2009-07-30

    Extracted babassu coconut (Orbignya speciosa) mesocarp (BCM) was applied as a biosorbent for aqueous Blue Remazol R160 (BR 160), Rubi S2G (R S2G), Red Remazol 5R (RR 5), Violet Remazol 5R (VR 5) and Indanthrene Olive Green (IOG) dye solutions. The natural sorbent was processed batchwise while varying several system parameters such as stirring time, pH and temperature. The interactions were assayed with respect to both pseudo-first-order and second-order reaction kinetics, with the latter the more suitable kinetic model. The maximum adsorption was obtained at pH 1.0 for all dyes due to available anionic groups attached to the structures, which can be justified by pH(pzc) 6.7 for the biosorbent BCM. The ability of babassu coconut mesocarp to adsorb dyes gave the order R S2G>VR 5>BR 160>IOG>RR 5, which data were best fit to Freundlich model, but did not well-adjusted for all dyes. The dye/biopolymer interactions at the solid/liquid interface are all spontaneous as given by free Gibbs energy, with exothermic enthalpic values of -26.1, -15.8, -17.8, -15.8 and -23.7 kJ mol(-1) for BR 160, R S2G, RR 5, IOG and VR 5, respectively. In spite of the negative entropic values contribution, the set of thermodynamic data is favorable for all dyes removal. However, the results pointed to the effectiveness of the mesocarp of babassu coconut as a biosorbent for removing textile dyes from aqueous solutions. PMID:19150173

  7. In Situ Mapping of the Molecular Arrangement of Amphiphilic Dye Molecules at the TiO2 Surface of Dye-Sensitized Solar Cells.

    PubMed

    Voïtchovsky, Kislon; Ashari-Astani, Negar; Tavernelli, Ivano; Tétreault, Nicolas; Rothlisberger, Ursula; Stellacci, Francesco; Grätzel, Michael; Harms, Hauke A

    2015-05-27

    Amphiphilic sensitizers are central to the function of dye-sensitized solar cells. It is known that the cell's performance depends on the molecular arrangement and the density of the dye on the semiconductor surface, but a molecular-level picture of the cell-electrolyte interface is still lacking. Here, we present subnanometer in situ atomic force microscopy images of the Z907 dye at the surface of TiO2 in a relevant liquid. Our results reveal changes in the conformation and the lateral arrangement of the dye molecules, depending on their average packing density on the surface. Complementary quantitative measurements on the ensemble of the film are obtained by the quartz-crystal microbalance with dissipation technique. An atomistic picture of the dye coverage-dependent packing, the effectiveness of the hydrophobic alkyl chains as blocking layer, and the solvent accessibility is obtained from molecular dynamics simulations. PMID:25936429

  8. A DNA Crystal Designed to Contain Two Molecules per Asymmetric Unit

    PubMed Central

    Wang, Tong; Sha, Ruojie; Birktoft, Jens; Zheng, Jianping; Mao, Chengde; Seeman, Nadrian C.

    2010-01-01

    We describe the self-assembly of a DNA crystal that contains two tensegrity triangle molecules per asymmetric unit. We have used X-ray crystallography to determine its crystal structure. In addition, we have demonstrated control over the colors of the crystals by attaching either Cy3 dye (pink) or Cy5 dye (blue-green) to the components of the crystal, yielding crystals of corresponding colors. Attaching the pair of dyes to the pair of molecules yields a purple crystal. PMID:20958065

  9. Post-Katrina fecal contamination in Violet Marsh near New Orleans.

    PubMed

    Furey, John S; Fredrickson, Herbert; Foote, Chris; Richmond, Margaret

    2007-06-01

    Fecal material entrained in New Orleans flood waters was pumped into the local environment. Violet Marsh received water pumped from St. Bernard Parish and the Lower Ninth Ward. Sediment core samples were collected from canals conducting water from these areas to pump stations and from locations within Violet Marsh. Viable indicator bacteria and fecal sterols were used to assess the levels of fecal material in sediment deposited after the levee failures and deeper sediments deposited before. Most of the cores had fecal coliform levels that exceed the biosolids criterion. All of the cores had fecal sterols that exceeded the suggested environmental quality criterion. Our data show both a long history of fecal contamination in Violet Marsh and an increase in fecal loading corresponding to the failure of the levee system. The work was performed as part of the Interagency Performance Evaluation Task Force investigation into the consequences of the failures of the New Orleans levee system. PMID:17617670

  10. Performing vaginal lavage, crystal violet staining, and vaginal cytological evaluation for mouse estrous cycle staging identification.

    PubMed

    McLean, Ashleigh C; Valenzuela, Nicolas; Fai, Stephen; Bennett, Steffany A L

    2012-01-01

    A rapid means of assessing reproductive status in rodents is useful not only in the study of reproductive dysfunction but is also required for the production of new mouse models of disease and investigations into the hormonal regulation of tissue degeneration (or regeneration) following pathological challenge. The murine reproductive (or estrous) cycle is divided into 4 stages: proestrus, estrus, metestrus, and diestrus. Defined fluctuations in circulating levels of the ovarian steroids 17-?-estradiol and progesterone, the gonadotropins luteinizing and follicle stimulating hormones, and the luteotropic hormone prolactin signal transition through these reproductive stages. Changes in cell typology within the murine vaginal canal reflect these underlying endocrine events. Daily assessment of the relative ratio of nucleated epithelial cells, cornified squamous epithelial cells, and leukocytes present in vaginal smears can be used to identify murine estrous stages. The degree of invasiveness, however, employed in collecting these samples can alter reproductive status and elicit an inflammatory response that can confound cytological assessment of smears. Here, we describe a simple, non-invasive protocol that can be used to determine the stage of the estrous cycle of a female mouse without altering her reproductive cycle. We detail how to differentiate between the four stages of the estrous cycle by collection and analysis of predominant cell typology in vaginal smears and we show how these changes can be interpreted with respect to endocrine status. PMID:23007862

  11. Microwave induced catalytic degradation of crystal violet in nano-nickel dioxide suspensions

    Microsoft Academic Search

    Huan He; Shaogui Yang; Kai Yu; Yongming Ju; Cheng Sun; Lianhong Wang

    2010-01-01

    Nickel oxide catalyst was obtained by precipitation–oxidation method with the assistance of microwave irradiation. The samples were characterized by X-ray diffraction, Raman spectrophotometer, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, surface area and porosity analyzer. On the basis of the results, the as-prepared product was nano-NiO2 with OH group and active oxygen. The catalytic activity of the as-prepared product might

  12. Enhancing the laser power by stacking multiple dye-doped chiral polymer films

    E-print Network

    Wu, Shin-Tson

    . Ozaki, "High Q defect mode and laser action in one-dimensional hybrid photonic crystal containing, and S. Mashiko, "Phototunable photonic bandgap in a chiral liquid crystal laser device," Appl. Phys in the backward direction than the forward one. This is due to the absorption of the laser dyes

  13. Dyeing of wool with natural anthraquinone dyes from Fusarium oxysporum

    Microsoft Academic Search

    F. A. Nagia; R. S. R. EL-Mohamedy

    2007-01-01

    Two anthraquinone compounds are described which were produced by liquid cultures of Fusarium oxysporum (isolate no. 4), isolated from the roots of citrus trees affected with root rot disease. These anthraquinone compounds are 2-acetyl-3,8-dihydroxy-6-methoxy anthraquinone or 3-acetyl-2,8-dihydroxy-6-methoxy anthraquinone. Dyeing of wool fabrics with these new anthraquinone compounds as natural dyes has been studied. The values of dyeing rate constant, half-time

  14. Fiberized fluorescent dye microtubes

    NASA Astrophysics Data System (ADS)

    Vladev, Veselin; Eftimov, Tinko

    2013-03-01

    In the present work we study the effect of the length of fluorescent dye-filled micro-capillaries on the fluorescence spectra. Two types of micro-capillaries have been studied: a 100 ?m inner diameter fused silica capillary with a transparent coating and one of the holes of a fiber optic glass ferrule with 125 ?m inner diameter. The tubes were filled with solutions of Rhodamine 6G dissolved in ethanol and then in glycerin. Experimental data show that the maximum fluorescence and the largest spectral widths are observed for a sample length of about 0.25 mm for the used concentration. This results show that miniature tunable fiberized dye lasers can be developed using available standard micro-and fibre-optic components.

  15. Painting With Natural Dyes

    NSDL National Science Digital Library

    Barbara Arrowtop (Heart Butte School)

    1999-07-01

    This activity is part of an integrated elementary unit called "Painted Tipis." The unit is best taught in the fall in conjunction with the September celebration "American Indian Heritage Week." It integrates lessons on literature through legends and myths, language (Blackfeet), and mathematics through structural components of the tipi. The activity introduces the students to the art of dyeing as used in ancestral tipi paintings. Historical cultural ties are an integral part of the Native American students learning and this unit provides those connections. The purpose of this lesson is to provide elementary students with the opportunity to explore, identify and locate area plants. The inquiry cooperative learning component of this lesson will be to determine the color (dye) producing possibilities of the plant. Students will also plan and carry out an experiment to produce the dyestuff of the plant as well as create possible mordants, which is a chemical or metallic compound that will "fasten" the color to the fabric.

  16. White light emission from polystyrene under pulsed ultra violet laser irradiation

    PubMed Central

    Kim, Eunkyeom; Kyhm, Jihoon; Kim, Jung Hyuk; Lee, Gi Yong; Ko, Doo-Hyun; Han, Il Ki; Ko, Hyungduk

    2013-01-01

    This paper reports for the first time the luminescent property of polystyrene (PS), produced by pulsed ultra violet laser irradiation. We have discovered that, in air, ultra-violet (UV) irradiated PS nanospheres emit bright white light with the dominant peak at 510?nm, while in vacuum they emit in the near-blue region. From the comparison of PS nanospheres irradiated in vacuum and air, we suggest that the white luminescence is due to the formation of carbonyl groups on the surface of PS by photochemical oxidation. Our results potentially offer a new route and strategy for white light sources. PMID:24247038

  17. Blue-violet photoluminescence from large-scale highly aligned boron carbonitride nanofibers

    NASA Astrophysics Data System (ADS)

    Bai, X. D.; Wang, E. G.; Yu, J.; Yang, Hui

    2000-07-01

    We report on the strong blue-violet photoluminescence (PL) at room temperature from the large-scale highly aligned boron carbonitride (BCN) nanofibers synthesized by bias-assisted hot filament chemical vapor deposition. The photoluminescence peak wavelength shifts in the range of 470-390 nm by changing the chemical composition of the BCN nanofibers, which shows an interesting blue and violet-light-emitting material with adjustable optical properties. The mechanism for the shift of the PL peaks at room temperature is also discussed.

  18. Optical trapping and fluorescence excitation with violet diode lasers and extended cavity surface emitting lasers

    NASA Astrophysics Data System (ADS)

    Lake, Tanya K.; Carruthers, Antonia E.; Taylor, Margaret; Paterson, Lynn; Gunn-Moore, Frank; Allen, John W.; Sibbett, Wilson; Dholakia, Kishan

    2004-02-01

    Violet diode lasers and vertical extended cavity surface emitting lasers are used within an optical trapping system. Two distinct but related studies are performed. Firstly, the optical trapping efficiency in terms of the Q parameter for micron and sub-micron sized particles is determined. Secondly, we use the violet diode laser to observe and fluoresce 4'-6- Diamidino-2-phenylindole (DAPI) stained chromosomes, green fluorescent protein (GFP) transfected neuroblastomas, and fluorescent polymer spheres within an optical tweezers using a 1064nm trap laser. This work paves the way for both reduced trap volumes and for biological tagging, chromosome selection, or observing protein dynamics.

  19. Retinal tolerance to dyes

    PubMed Central

    Lüke, C; Lüke, M; Dietlein, T S; Hueber, A; Jordan, J; Sickel, W; Kirchhof, B

    2005-01-01

    Background: Dye solutions for intraoperative staining of epiretinal membranes and the internal limiting membrane improve the visualisation of these thin structures and facilitate their removal. In the present study the authors investigated the effects of indocyanine green 0.05%, trypan blue 0.15%, and patent blue 0.48% on bovine retinal function. Methods: Bovine retina preparations were perfused with a standard solution and the electroretinogram (ERG) was recorded repeatedly. After recording of stable ERG amplitudes the nutrient solution was substituted by one of the dye solutions. The duration of retinal exposure to a dye solution was varied between 10 seconds and 2 minutes. Thereupon, the preparation was reperfused with standard solution for at least 115 minutes. The percentage of b-wave reduction after exposition was calculated. Results: Reductions of the b-wave amplitude were found for each dye solution tested. The effects after application of patent blue and indocyanine green were completely reversible within the recovery time for an exposure period of 60 and 30 seconds, respectively. The application of trypan blue lead to a loss of the b-wave when the retina was exposed for 15 seconds or longer. This effect was only partly reversible within the recovery time. Conclusion: The ERG showed toxic effects of trypan blue after a short period of retinal exposure. The intraocular application of trypan blue should be limited to selected cases. However, intraocular application of indocyanine green and patent blue in a sufficient concentration and taking account of a short period of retinal exposure seems possible. PMID:16113379

  20. Dye laser tuner

    SciTech Connect

    Arthurs, E.G.; Purdie, A.F.

    1980-11-11

    A laser of the kind in which the lasing medium is a free flowing dye stream incorporates a means of tuning the output wave length of the laser, this means being in the form of a wedged birefringent plate which is driven in a linear mode by a linear translator so that the thickness of the birefringent plate traversed by the intracavity beam of laser light may be varied.

  1. Study of a natural dye solubilisation in o\\/w microemulsions and its dyeing behaviour

    Microsoft Academic Search

    Roshan Paul; Conxita Solans; Pilar Erra

    2005-01-01

    The manufacture of synthetic dyes involves many non eco-friendly chemical procedures. For this reason, the application of natural dyes in textile dyeing is being explored worldwide. The dye exhaustion, fixation and levelness of dyeing depends on several factors such as the properties of fibres, the molecular structure of dyes, and the medium of the dyebath. The solubilisation of insoluble natural

  2. Dye-coated europium monosulfide

    SciTech Connect

    Kar, Srotoswini [Department of Chemistry, Georgetown University, Washington D.C. 20057 (United States); Dollahon, Norman R. [Department of Biology, Villanova University, Villanova, PA 19085 (United States); Stoll, Sarah L., E-mail: sls55@georgetown.ed [Department of Chemistry, Georgetown University, Washington D.C. 20057 (United States)

    2011-05-15

    Nanoparticles of EuS were synthesized using europium dithiocarbamate complexes. The resulting nanoparticles were coated with the dye, 1-pyrene carboxylic acid and the resulting material was characterized using X-ray powder diffraction, TEM, and UV-visible spectroscopy. Fluorescence spectroscopy was used to determine the relative energy of the conduction band edge to the excited state energy of the dye. -- Graphical abstract: Dye sensitized magnetic semiconductor materials were prepared by synthesizing EuS nanoparticles using single source precursors and coating with the dye, 1-pyrene carboxylic acid. Display Omitted highlights: > Synthesized EuS nanoparticles, 11{+-}2.4 nm characterized using XRD, TEM, and UV-vis. spect. > Grafted a dye to the surface and characterized the product using XRD, FTIR, UV-vis., and TEM. > Studied the photophysical properties using fluorescence spectroscopy. > Determined the relative dye excited state to the conduction band of the semiconductor.

  3. 75 FR 23239 - Carbazole Violet Pigment 23 From India: Extension of Time Limit for Final Results of Antidumping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-03

    ...International Trade Administration [A-533-838] Carbazole Violet Pigment 23 From India: Extension of Time Limit for Final Results of...antidumping duty order on CVP 23 from India. See Carbazole Violet Pigment 23 from India: Preliminary Results of Antidumping Duty...

  4. Tunable liquid crystal lasers

    NASA Astrophysics Data System (ADS)

    Woltman, Scott J.

    Liquid crystal lasers are dye-doped distributed feedback lasing systems. Fabricated by coupling the periodic structure of a liquid crystal medium with a fluorescent dye, the emission from these systems is tunable by controlling the liquid crystal system---be it through electric or thermal field effects, photochemical reactions, mechanical deformations, etc. The laser action arises from an extended interaction time between the radiation field, the laser emission, and the matter field, the periodic liquid crystal medium, at the edge of the photonic band gap. In this thesis, several tunable liquid crystal laser systems are investigated: cholesteric liquid crystals, holographic-polymer dispersed liquid crystals and liquid crystal polarization gratings. The primary focus has been to fabricate systems that are tunable through electrical means, as applications requiring mechanical or thermal changes are often difficult to control. Cholesteric liquid crystal lasers are helical Bragg reflectors, with a band gap for circularly polarized light of equivalent handedness to their helix. These materials were doped with a laser dye and laser emission was observed. The use of an in-plane electric field tends to unwind the helical pitch of the film and in doing so tunable emission was demonstrated for ˜15 nm. Holographic-polymer dispersed liquid crystals (H-PDLCs) are grating structures consisting of alternating layers of polymer and liquid crystal, with different indices of refraction. The application of an electric field index matches these layers and switches off the grating. Thus, laser emission can be switched on and off through the use of an electric field. Spatially tunable H-PDLC lasers were fabricated by creating chirped gratings, formed by divergent beams. The emission was shown to tune ˜5 nm as the pump beam was translated across a 1 inch film. Liquid crystal polarization gratings use photo-patterned alignment layers, through a polarization holography exposure, to induce an alignment in a liquid crystal film. Electrically tunable emission was demonstrated in these systems. Applications of liquid crystal lasers include emissive substrates or backplanes for displays or tunable emission sources for biology and medicine. The potential for such applications are discussed.

  5. Locating Electron Swarms in Hydrogen by Far Ultra-Violet Signals

    Microsoft Academic Search

    J. M. Breare; A. von Engel

    1964-01-01

    An electron swarm is released from a pulsed gas discharge and passes through a hydrogen-filled chamber in which a uniform electric field is maintained whereby some electrons excite and ionize gas molecules by collisions. From observations of the ultra-violet signals released by the truncated electron swarm, one can derive the drift velocity of electrons, the diffusion coefficient and the degree

  6. American Institute of Aeronautics and Astronautics Violet: A High-Agility Nanosatellite for Demonstrating

    E-print Network

    Peck, Mason A.

    CMGs, Violet is capable of hosting guest investigators' steering algorithms for a variety of CMG ultraviolet telescope, which includes flight-spare Deep Impact CCDs and serves as a representative payload enables a satellite to slew its payload quickly through large angles, which helps maximize the time during

  7. Photochemical damage to skin fibroblasts caused by protoporphyrin and violet light

    Microsoft Academic Search

    A. A. Schothorst; C. A. C. De Haas; D. Suurmond

    1980-01-01

    Foreskin fibroblasts cultured in a medium containing protoporphyrin and exposed to violet light lose the capacity to proliferate. This phenomenon can be assessed on the basis of the ability of the irradiated cells to form colonies. Potentially lethal injuries can, however, be repaired during post-irradiation incubation under optimal growth conditions. We investigated the photodynamically induced transformations of certain molecular targets

  8. 21 CFR 500.29 - Gentian violet for use in animal feed.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    21 ? Food and Drugs ? 6 ? 2011-04-01 ? 2011-04-01 ? false ? Gentian violet for use in animal feed. ? 500.29 ? Section 500.29 ? Food and Drugs ? FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ? ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ? GENERAL ?...

  9. Proof of ultra-violet finiteness for a planar non-supersymmetric Yang-Mills theory

    E-print Network

    Sudarshan Ananth; Stefano Kovacs; Hidehiko Shimada

    2007-07-31

    This paper focuses on a three-parameter deformation of N=4 Yang-Mills that breaks all the supersymmetry in the theory. We show that the resulting non-supersymmetric gauge theory is scale invariant, in the planar approximation, by proving that its Green functions are ultra-violet finite to all orders in light-cone perturbation theory.

  10. Selection of an Analysis Wavelength: An Interesting Example Involving Solvatochromism and the Zwitterionic Dimroth-Reichardt's Betaine ET-30 Dye

    NASA Astrophysics Data System (ADS)

    Deng, Taihe; Acree, William E., Jr.

    1999-11-01

    A laboratory experiment is designed for studying the solvatochromic behavior of the zwitterionic Dimroth-Reichardt's betaine ET-30 dye. By spectrophotometric measurements, students determine the analysis wavelength for ET-30 dissolved in solvents of varying polarity. The five solvents selected for study give solutions that appear wine-red, violet, blue, green, and yellowish-green. Student observations afford an excellent opportunity for detailed discussions of how solvent polarity affects spectral transitions, which expands the presentation given in most analytical textbooks. Textbook presentations generally represent absorption and emission transitions in the form of a Jablonski diagram, with no discussion of solvatochromism and solvent-dependent wavelength shifts.

  11. Dye labeling retinal ganglion cell axons in live Xenopus tadpoles.

    PubMed

    Ruthazer, Edward S; Schohl, Anne; Schwartz, Neil; Tavakoli, Aydin; Tremblay, Marc; Cline, Hollis T

    2013-08-01

    Individual neurons in the developing nervous system can be visualized by the targeted delivery of a fluorophore. In this article, we describe a method for introducing a fluorescent dye via iontophoresis into retinal ganglion cell (RGC) axons in albino Xenopus laevis tadpoles. Iontophoresis is the enhanced permeation of molecules across biological membranes under the influence of an electrical field. Lipophilic dyes such as DiI are well suited to this method--being insoluble in the aqueous environment of the eye, they precipitate instantaneously, and only cells in contact with the dye crystal are labeled as the dye diffuses through the plasma membrane. A dissection stereomicroscope is used to allow a wide range of approach angles for the micropipette. The goal is to introduce a small bolus of dye into the neural retina where the ganglion cell somata are located and the axons course, with the expectation that it will be taken up by a small enough number of axons to allow individual cells to be distinguished. Because RGC axons will typically be imaged in the tectum far from the injection site, a relatively large injection can be made, increasing the probability of labeling axons without obscuring their visualization at the target. This approach is particularly useful under conditions in which it might be too difficult to perform juxtacellular electroporation because of limited visibility or access. PMID:23906914

  12. Ultra-violet Sensing Characteristic and Field Emission Properties of Vertically Aligned Aluminum Doped Zinc Oxide Nanorod Arrays

    SciTech Connect

    Mamat, M. H.; Malek, M. F.; Musa, M. Z. [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); Khusaimi, Z. [NANO-SciTech Centre (NST), Institute of Science (IOS), Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia); Rusop, M. [NANO-ElecTronic Centre (NET), Faculty of Electrical Engineering, Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia) and NANO-SciTech Centre (NST), Institute of Science (IOS), Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia)

    2011-05-25

    Ultra-violet (UV) sensing behavior and field emission characteristic have been investigated on vertically aligned aluminum (Al) doped zinc oxide (ZnO) nanorod arrays prepared using sol-gel immersion method. Uniform and high coverage density of ZnO nanorod arrays have been successfully deposited on seeded-catalyst coated substrates. The synthesized nanorods have diameter sizes between 50 nm to 150 nm. The XRD spectra show Al doped ZnO nanorod array has high crystallinity properties with the dominancy of crystal growth along (002) plane or c-axis. UV photoresponse measurement indicates that Al doped ZnO nanorod array sensitively detects UV light as shown by conductance increment after UV illumination exposure. The nanorod array shows good field emission properties with low turn on field and threshold field at 2.1 V/{mu}m and 5.6 V/{mu}m, respectively. The result suggested that Al doped ZnO nanorod arrays prepared by low-cost sol-gel immersion method show promising result towards fabrication of multi applications especially in UV photoconductive sensor and field emission displays.

  13. Dye Sensitized Solar Cells

    PubMed Central

    Wei, Di

    2010-01-01

    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. PMID:20480003

  14. Gel Electrophoresis of Dyes

    NSDL National Science Digital Library

    Janice Stephens

    2011-01-01

    In this experiment related to plant biotechnology, learners discover how to prepare and load an electrophoresis gel. They will then run the gels in an electrophoresis system to separate several dyes that are of different molecular sizes and carry different charges. This technique is fundamental to many of the procedures used in biotechnology. This lesson guide includes background information for the educator, safety precautions, and questions with answers for learners. For safety reasons, adult supervision is recommended. Modifications for use with younger learners are described in a related PDF (see related resource).

  15. Effects of pH of Dyes on Characteristics of Dye-Sensitized Solar Cells

    Microsoft Academic Search

    Shoji Furukawa; Hiroshi Iino; Koudai Kukita; Kaoru Kaminosono

    2010-01-01

    Dye-sensitized solar cells were fabricated using natural dyes and synthesized dyes in which rear metal was not contained. Effects of pH of dyes on the characteristics of the dye-sensitized solar cells were also examined. As a result, it was found that the conversion efficiency of the dye-sensitized solar cell fabricated using red-cabbage dye with a pH of 2.5 was 0.10

  16. Synthesis and characterization of triphenylamine-based organic dyes for dye-sensitized solar cells

    Microsoft Academic Search

    Jihyun Heo; Jin-Woo Oh; Ho-Ik Ahn; Su-Bin Lee; Sang-Eun Cho; Mi-Ra Kim; Jin-Kook Lee; Nakjoong Kim

    2010-01-01

    We synthesized three organic dyes (DYE 1, DYE 2, and DYE 3) containing triphenylamine (TPA) moieties as electron donors and cyanoacrylic acid moieties as electron acceptors, designed at the molecular level, and developed them for use in dye-sensitized solar cells (DSSCs). Among all the dyes, DYE 2 exhibited the highest overall solar-energy-to-electricity conversion efficiency of 4.06% with a short-circuit photocurrent

  17. Fluorometric procedures for dye tracing

    USGS Publications Warehouse

    Wilson, James E., Jr.; Cobb, E.D.; Kilpatrick, F.A.

    1984-01-01

    This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The outstanding characteristics of dye tracing are: (1) the low detection and measurement limits, and (2) the simplicity and accuracy of measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a general guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section is included on aerial photography because of its possible use to supplement ground-level fluorometry. (USGS)

  18. Fluorometric procedures for dye tracing

    USGS Publications Warehouse

    Wilson, James F.; Cobb, Ernest D.; Kilpatrick, F.A.

    1986-01-01

    This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section on aerial photography is included because of its possible use to supplement ground-level fluorometry.

  19. Fluorometric procedures for dye tracing

    USGS Publications Warehouse

    Wilson, James F.

    1968-01-01

    This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary background information about fluorescence, dyes, and fluorometers and a description of fluorometric operation and calibration procedures as a guide for laboratory and field use. The background information should be useful to anyone wishing to experiment with dyes, fluorometer components, or procedures different from those described. In addition, a brief section on aerial photography is included because of its possible use to supplement ground-level fluorometry.

  20. Colouring mechanism of dyed KDP crystal by quantum chemistry

    Microsoft Academic Search

    Yusuke Asakuma; Motosuke Nishimura; Qin Li; H. Ming Ang; Moses Tade; Kouji Maeda; Keisuke Fukui

    2007-01-01

    Dye adsorption mechanism, in particular, colouring mechanism of KDP (KH2PO4) crystal was investigated by quantum chemistry in this study. Phenomena, such as different preferentially coloured faces of KDP when co-crystallised with different dyes, are explained by the minimum and maximum values of electrostatic potential (ESP). Furthermore, it is found that the ESP distribution of a dye molecule may not necessarily

  1. Levitated droplet dye laser

    E-print Network

    Azzouz, H; Balslev, S; Johansson, J; Mortensen, N A; Nilsson, S; Kristensen, A

    2006-01-01

    We present the first observation, to our knowledge, of lasing from a levitated, dye droplet. The levitated droplets are created by computer controlled pico-liter dispensing into one of the nodes of a standing ultrasonic wave (100 kHz), where the droplet is trapped. The free hanging droplet forms 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 spectrometer. With this setup we have achieved reproducible lasing spectra in the visible wavelength range from 610 nm to 650 nm. The levitated droplet technique has previously successfully been applied for a variety of bio-analytical applications at single cell level. In combination with the lasing droplets, the capability of this high precision setup has potential applications within highly sensitive intra-cavity absorban...

  2. Levitated droplet dye laser

    NASA Astrophysics Data System (ADS)

    Azzouz, H.; Alkhafadiji, L.; Balslev, S.; Johansson, J.; Mortensen, N. A.; Nilsson, S.; Kristensen, A.

    2006-05-01

    We present the first observation, to our knowledge, of lasing from a levitated, dye droplet. The levitated droplets are created by computer controlled pico-liter dispensing into one of the nodes of a standing ultrasonic wave (100 kHz), where the droplet is trapped. The free hanging droplet forms 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 spectrometer. With this setup we have achieved reproducible lasing spectra in the visible wavelength range from 610 nm to 650 nm. The levitated droplet technique has previously successfully been applied for a variety of bio-analytical applications at single cell level. In combination with the lasing droplets, the capability of this high precision setup has potential applications within highly sensitive intra-cavity absorbance detection.

  3. Tunable photonic devices based on the temperature dependent photonic band gap in chiral nematic liquid crystals

    E-print Network

    Wu, Shin-Tson

    a spatially tunable laser emission by generating a one-dimensional temperature gradient along the dye fluorescence emission of the dye. 1. INTRODUCTION Cholesteric liquid crystal (CLC) is a simple one-dimensional liquid crystals Yuhua Huang, Ying Zhou, and Shin-Tson Wu College of Optics and Photonics, University

  4. Soybean peroxidase-mediated degradation of an azo dye– a detailed mechanistic study

    PubMed Central

    2013-01-01

    Background Peroxidases are emerging as an important class of enzymes that can be used for the efficient degradation of organic pollutants. However, detailed studies identifying the various intermediates produced and the mechanisms involved in the enzyme-mediated pollutant degradation are not widely published. Results In the present study, the enzymatic degradation of an azo dye (Crystal Ponceau 6R, CP6R) was studied using commercially available soybean peroxidase (SBP) enzyme. Several operational parameters affecting the enzymatic degradation of dye were evaluated and optimized, such as initial dye concentration, H2O2 dosage, mediator amount and pH of the solution. Under optimized conditions, 40 ppm dye solution could be completely degraded in under one minute by SBP in the presence of H2O2 and a redox mediator. Dye degradation was also confirmed using HPLC and TOC analyses, which showed that most of the dye was being mineralized to CO2 in the process. Conclusions Detailed analysis of metabolites, based on LC/MS results, showed that the enzyme-based degradation of the CP6R dye proceeded in two different reaction pathways- via symmetric azo bond cleavage as well as asymmetric azo bond breakage in the dye molecule. In addition, various critical transformative and oxidative steps such as deamination, desulfonation, keto-oxidation are explained on an electronic level. Furthermore, LC/MS/MS analyses confirmed that the end products in both pathways were small chain aliphatic carboxylic acids. PMID:24308857

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

    Microsoft Academic Search

    Sancun Hao; Jihuai Wu; Yunfang Huang; Jianming Lin

    2006-01-01

    The dye-sensitized solar cells (DSC) were assembled by using natural dyes extracted from black rice, capsicum, erythrina variegata flower, rosa xanthina, and kelp as sensitizers. The ISC from 1.142mA to 0.225mA, the VOC from 0.551V to 0.412V, the fill factor from 0.52 to 0.63, and Pmax from 58?W to 327?W were obtained from the DSC sensitized with natural dye extracts.

  6. Dielectric and thermal effects on the optical properties of natural dyes: a case study on solvated cyanin.

    PubMed

    Malc?o?lu, Osman Bari?; Calzolari, Arrigo; Gebauer, Ralph; Varsano, Daniele; Baroni, Stefano

    2011-10-01

    The optical properties of the flavylium state of the cyanin dye are simulated numerically by combining Car-Parrinello molecular dynamics and linear-response time-dependent density functional theory calculations. The spectrum of the dye calculated in the gas phase is characterized by two peaks in the yellow and in the blue (green and violet), using a GGA-PBE (hybrid-B3LYP) DFT functional, which would bring about a greenish (bright orange) color incompatible with the dark purple hue observed in nature. Describing the effect of the water solvent through a polarizable continuum model does not modify qualitatively the resulting picture. An explicit simulation of both solvent and thermal effects using ab initio molecular dynamics results instead in a spectrum that is compatible with the observed coloration. This result is analyzed in terms of the spectroscopic effects of the molecular distortions induced by thermal fluctuations. PMID:21905678

  7. Decolorization of textile dyes by fungal pellets

    Microsoft Academic Search

    Ozfer Yesilada; Dilek Asma; Seval Cing

    2003-01-01

    Decolorization of various dyes by pellets of white rot fungi was studied. All fungal pellets used could remove more than 75% of the color of these dyes in 24 h. Effect of various conditions such as initial pH, concentration of dye, amount of pellet, temperature and agitation on Astrazone blue dye decolorization activity of Funalia trogii was tested and the

  8. Dye-sensitized solar cells

    DOEpatents

    Skotheim, Terje A. [Berkeley, CA

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

  9. Dye-sensitized solar cells

    DOEpatents

    Skotheim, T.A.

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

  10. nanostructures for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Rashad, M. M.; Shalan, A. E.

    2014-08-01

    Hierarchical architectures consisting of one-dimensional (1D) nanostructures are of great interest for potential use in energy and environmental applications in recent years. In this work, hierarchical tungsten oxide (WO3) has been synthesized via a facile hydrothermal route from ammonium metatungstate hydrate and implemented as photoelectrode for dye-sensitized solar cells. The urchin-like WO3 micro-patterns are constructed by self-organized nanoscale length 1D building blocks, which are single crystalline in nature, grown along (001) direction and confirm an orthorhombic crystal phase. The obtained powders were investigated by XRD, SEM, TEM and UV-Vis Spectroscopy. The photovoltaic performance of dye-sensitized solar cells based on WO3 photoanodes was investigated. With increasing the calcination temperature of the prepared nanopowders, the light-electricity conversion efficiency ( ?) was increased. The results were attributed to increase the crystallinity of the particles and ease of electron movement. The DSSC based on hierarchical WO3 showed a short-circuit current, an open-circuit voltage, a fill factor, and a conversion efficiency of 4.241 mA/cm2, 0.656 V, 66.74, and 1.85 %, respectively.

  11. Dyeing Properties of Natural Dye Syzygium cuminii on Silk

    NASA Astrophysics Data System (ADS)

    Narayana Swamy, V.; Ninge Gowda, K. N.; Sudhakar, R.

    2014-04-01

    Dyeing behavior of natural dye extracted from the bark of Syzygium cuminii L has been studied on silk fabric. Colour values and colour co-ordinates were examined in terms of K/S and L* a* b* C and h. A range of shades were obtained by using various mordants and mordanting techniques. Dye was tested for some of the eco-parameters using atomic absorption spectrophotometry and GC/MS. The test results were compared with the set standards to determine the eco-friendliness of natural dye. Their concentrations were much below the stipulated limits. Dyed samples were tested for antimicrobial activity against Gram-positive and Gram-negative bacteria and were found to possess antibacterial activity.

  12. Electrochemically self-assembled ZnO/dye electrodes: preparation and time-resolved photoelectrochemical measurements

    NASA Astrophysics Data System (ADS)

    Schlettwein, Derck; Oekermann, Torsten; Yoshida, Tsukasa; Sugiura, Takashi; Minoura, Hideki; Wohrle, Dieter

    2002-11-01

    Dye-modified ZnO thin films were prepared by electrochemically induced crystallization from aqueous mixtures of zinc nitrate and water-soluble dyes. A direct crystallization of semiconductor/ dye composites without heat treatment is seen as a significant advantage of this method. Moreover, characterization of these materials has revealed ordered growth of ZnO crystallites as well as formation of ordered dye assemblies, thus characterizing this method as electrochemical self-assembly. The photoelectrochemical properties of these unique ZnO-dye thin film electrodes were investigated in photocurrent transient measurements in the ms-regime and by steady- state voltammetric measurements. Two sets of electrodes are discussed, employing either metal complexes of tetrasulfophthalocyanines (TSPcMt; Mt = Zn, Al, Si) or the xanthene dye Eosin Y. For aggregates of TSPcMt on ZnO, efficient charge-transfer to the electrolyte is found, leading to low surface charging and low surface recombination of photogenerated holes with electrons from the ZnO, at however, rather low injection efficiencies of electrons into the conduction band of ZnO. This efficiency was higher for adsorbed monomers of TSPcMt leading to a considerably higher quantum efficiency of the photocurrent in spite of increased surface charging and recombination of holes. Higher photocurrents were observed for ZnO sensitized with monomers of Eosin Y caused by both, efficient electron transfer from the dye to ZnO as well as hole transfer from the dye to the electrolyte. Not only dye molecules which were directly accessible from the electrolyte, but also those which were enclosed within matrix cavities proved to be photoelectrochemically active.

  13. Optimization of extraction and dyeing conditions for traditional turmeric dye

    Microsoft Academic Search

    Kiran Sachan; VP Kapoor

    Water soluble yellow dye was extracted from turmeric rhizomes (Curcuma longa L.), collected from Lucknow, Shillong and from local market, through aqueous\\/solvent extraction procedure using vacuum evaporator and spray drying of aqueous extract. Shillong sample was found to contain higher dye content (21.3-27.6%) followed by Lucknow sample (15.5- 18.9%) and market sample (14.0-18.2%). Shillong sample was also been found to

  14. Trend towards low cost, low power, ultra-violet (UV) based biological agent detectors

    NASA Astrophysics Data System (ADS)

    Sickenberger, David

    2005-11-01

    Ultra-violet fluorescence remains a corner stone technique for the detection of biological agent aerosols. Historically, these UV based detectors have employed relatively costly and power demanding lasers that have influenced the exploitation of the technology to wider use. Recent advancements from the Defense Advanced Research Project Agency's (DARPA) Solid-state Ultra Violet Optical Sources (SUVOS) program has changed this. The UV light emitting diode (LED) devices based on Gallium Nitride offer a unique opportunity to produce small, low power, and inexpensive detectors. It may, in fact, be possible to extend the SUVOS technology into detectors that are potentially disposable. This report will present ongoing efforts to explore this possibility. It will present candidate UV fluorescence based detector designs along with the biological aerosol responses obtained from these designs.

  15. RESONANCE LIGHT SCATTERING FOR THE DETERMINATION OF NUCLEIC ACIDS WITH METHYL VIOLET

    Microsoft Academic Search

    Wu Juan Zhang; Hong Ping Xu; Chun Xia Xue; Xing Guo Chen; Zhi De Hu

    2001-01-01

    For the first time, methyl violet (MV) was used to determine nucleic acids with a resonance light scattering (RLS) technique. The interactions of MV with nucleic acids give strong signals of RLS at 327.0, 490.0 and 651.0 nm. Based on this reaction, a new quantitative determination method for nucleic acids in aqueous solutions has been developed. At pH 7.51 and

  16. Acylated cyanidin 3-sophoroside-5-glucoside in purple-violet flowers of Moricandia arvensis (Brassicaceae).

    PubMed

    Tatsuzawa, Fumi; Kato, Kazuhisa; Sato, Motoki; Ito, Shun; Muraoka, Hiroki; Takahata, Yoshihito; Ogawa, Satoshi

    2015-03-01

    A new acylated anthocyanin was isolated as a major pigment, along with a known anthocyanin (Moricandia arvensis anthocyanin 1: MAA-1), from a strain of Moricandia arvensis (Code No. MOR-ARV-3) with purple-violet flowers, and identified as cyanidin 3-O-[2-O-(2-O-(4-O-(6-O-(4-O-(?-glucopyranosyl)-trans-caffeoyl)-?-glucopyranosyl)-trans-sinapoyl)-?-glucopyranoside]-5-O-[6-O-(malonyl)-?-glucopyranoside]. PMID:25924529

  17. Quantitative thermographic analysis method for evaluating the thermal properties of PET irradiated by ultra-violet

    Microsoft Academic Search

    Hae Young Choi; Jung Soon Lee

    2008-01-01

    A thermograph is used to determine the real-time temperature distribution on the skin temperature wearing clothing treated\\u000a by different ultra-violet (UV) energy. The thermogram images of body wearing clothing with the 4-channel PET knit fabric irradiated\\u000a by UV, were compared visually with each other and analyzed quantitatively with image analysis. We analyzed the thermogram\\u000a in a color image. For image

  18. Cavity-enhanced absorption: detection of nitrogen dioxide and iodine monoxide using a violet laser diode

    Microsoft Academic Search

    V. L. Kasyutich; C. S. E. Bale; C. E. Canosa-Mas; C. Pfrang; S. Vaughan; R. P. Wayne

    2003-01-01

    .   We present an application of cavity-enhanced absorption spectroscopy with an off-axis alignment of the cavity formed by two\\u000a spherical mirrors and with time integration of the cavity-output intensity for detection of nitrogen dioxide (NO2) and iodine monoxide (IO) radicals using a violet laser diode at ?=404.278 nm. A noise-equivalent (1?? root-mean-square variation\\u000a of the signal) fractional absorption for one optical

  19. Cavity-enhanced absorption: detection of nitrogen dioxide and iodine monoxide using a violet laser diode

    Microsoft Academic Search

    V. L. Kasyutich; C. S. E. Bale; C. E. Canosa-Mas; C. Pfrang; S. Vaughan; R. P. Wayne

    2003-01-01

    We present an application of cavity-enhanced absorption spectroscopy with an off-axis alignment of the cavity formed by two spherical mirrors and with time integration of the cavity-output intensity for detection of nitrogen dioxide (NO2) and iodine monoxide (IO) radicals using a violet laser diode at lambda=404.278 nm. A noise-equivalent (1sigma? root-mean-square variation of the signal) fractional absorption for one optical

  20. Mode locking in monolithic two-section InGaN blue-violet semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Vasil'ev, P. P.; Sergeev, A. B.; Smetanin, I. V.; Weig, T.; Schwarz, U. T.; Sulmoni, L.; Dorsaz, J.; Lamy, J.-M.; Carlin, J.-F.; Grandjean, N.; Zeng, X.; Stadelmann, T.; Grossmann, S.; Hoogerwerf, A. C.; Boiko, D. L.

    2013-03-01

    Passive mode-locked pulses with repetition frequencies in the range 40 to 90 GHz were observed in blue-violet GaN-based quantum-well lasers without external cavities. The lasers had two-section geometry with built-in saturable absorber section. The individual pulses had durations as short as 3-5 ps at peak powers of around 320 mW.

  1. Optical dialysis adequacy sensor: contribution of chromophores to the ultra violet absorbance in the spent dialysate

    Microsoft Academic Search

    Kai Lauri; Risto Tanner; Merike Luman; J. Jerotskaj; I. Fridolin

    2006-01-01

    Several on-line methods have been developed to standardize the assessment of dialysis adequacy. Earlier studies have demonstrated that on-line monitoring of total ultra violet (UV) absorbance in spent dialysate can be utilized to follow continuously a single hemodialysis session. The aim of this study was to investigate the contribution of different compounds, acting as chromophores, to the UV-absorbance in the

  2. Development of an Ultra-Violet Digital Camera for Volcanic Sulfur Dioxide Imaging

    Microsoft Academic Search

    G. J. Bluth; J. M. Shannon; I. M. Watson; F. J. Prata; V. J. Realmuto

    2006-01-01

    In an effort to improve monitoring of passive volcano degassing, we have constructed and tested a digital camera for quantifying the sulfur dioxide (SO2) content of volcanic plumes. The camera utilizes a bandpass filter to collect photons in the ultra-violet (UV) region where SO2 selectively absorbs UV light. SO2 is quantified by imaging calibration cells of known SO2 concentrations. Images

  3. Development of an ultra-violet digital camera for volcanic SO 2 imaging

    Microsoft Academic Search

    G. J. S. Bluth; J. M. Shannon; I. M. Watson; A. J. Prata; V. J. Realmuto

    2007-01-01

    In an effort to improve monitoring of passive volcano degassing, we have constructed and tested a digital camera for quantifying the sulfur dioxide (SO2) content of volcanic plumes. The camera utilizes a bandpass filter to collect photons in the ultra-violet (UV) region where SO2 selectively absorbs UV light. SO2 is quantified by imaging calibration cells of known SO2 concentrations.Images of

  4. Development of an ultra-violet digital camera for volcanic SO2 imaging

    Microsoft Academic Search

    G. J. S. Bluth; J. M. Shannon; I. M. Watson; A. J. Prata; V. J. Realmuto

    2007-01-01

    In an effort to improve monitoring of passive volcano degassing, we have constructed and tested a digital camera for quantifying the sulfur dioxide (SO2) content of volcanic plumes. The camera utilizes a bandpass filter to collect photons in the ultra-violet (UV) region where SO2 selectively absorbs UV light. SO2 is quantified by imaging calibration cells of known SO2 concentrations. Images

  5. Recent progress of high-power InGaN blue-violet laser diodes

    Microsoft Academic Search

    H. Y. Ryu; K. H. Ha; S. N. Lee; K. K. Choi; T. Jang; J. K. Son; H. G. Kim; J. H. Chae; H. S. Paek; Y. J. Sung; T. Sakong; K. S. Kim; O. H. Nam; Y. J. Park

    2006-01-01

    We report on the development of GaN-based violet laser diodes (LDs) for the high-capacity optical storage application and blue LDs for the laser projection display application. InGaN LDs with emission wavelength of ~405 nm are already being adopted for next-generation optical-storage systems. We present results on >400 mW single-mode output power under pulsed operation which can be employed in 100

  6. Effect of Accelerated Ultra Violet and Thermal Exposure on Nano Scale Mechanical Properties of Nylon Fibers

    Microsoft Academic Search

    Nandula Wanasekara; Vijaya Chalivendra; Paul Calvert

    \\u000a Nano-characterization studies using atomic force microscopy (AFM) was conducted to study the effect of accelerated ultra violet\\u000a (UV) and thermal degradation on mechanical properties of Nylon textile fibers. Nylon fibers were exposed to UV radiation for\\u000a six different hours using Q-UV Panel Weatherometer. The exposed fibers were molded in an epoxy plug for nanaoindentation using\\u000a AFM. Progressive nanoindentation from surface

  7. Spectral enhancement of leucocrystal violet treated footwear impression evidence in blood.

    PubMed

    Spence, Lindsay; Asmussen, Gary

    2003-03-27

    The results presented demonstrate the capacity for spectral enhancement to substantially improve the forensic examination of footwear impressions in blood treated with leucocrystal violet (LCV). The UV-Vis absorption spectra were generated of (i) an aqueous solution of leucocrystal violet, (ii) leucocrystal violet in 3% H(2)O(2), (iii) LCV working solution and (iv) whole blood added to LCV working solution. The resultant fluorescence emission spectra were subsequently generated (lambda(ex)=630nm, lambda(em)=661-900nm). The results indicate that the UV-Vis absorption spectra of an unbuffered solution of whole blood with LCV working solution produces a strong absorbance curve with a maxima at 630nm. Subsequent excitation at this wavelength and generation of the emission spectrum in the fluorescence mode indicates that a solution of whole blood added to LCV working solution is an extremely weak fluorophore. Therefore, to enable an adequate and timely enhancement of blood impression evidence treated with LCV utilising either visible fluorescence or infrared luminescence requires (i) selection of the most appropriate excitation wavelength (lambda(ex)) and emission wavelength (lambda(em)) with extremely narrow band pass filters, which in the absence of substrate matrix interference is excitation at 630nm producing the emission maxima at 665nm and (ii) a visual enhancement system such as a CCD colour IR video camera with image integration. PMID:12711191

  8. A violet emission in ZnS:Mn,Eu: Luminescence and applications for radiation detection

    SciTech Connect

    Ma, Lun; Chen, Wei, E-mail: weichen@uta.edu [Department of Physics and the SAVANT Center, The University of Texas at Arlington, Arlington, Texas 76019-0059 (United States); Jiang, Ke [Center for Biofrontiers Institute, University of Colorado at Colorado Springs, 1420 Austin Bluffs Pkwy., Colorado Springs, Colorado 80918 (United States); Liu, Xiao-tang [Department of Physics and the SAVANT Center, The University of Texas at Arlington, Arlington, Texas 76019-0059 (United States); Department of Applied Chemistry, College of Science, South China Agricultural University, Guangzhou 510642 (China)

    2014-03-14

    We prepared manganese and europium co-doped zinc sulfide (ZnS:Mn,Eu) phosphors and used them for radiation detection. In addition to the red fluorescence at 583?nm due to the d-d transition of Mn ions, an intense violet emission at 420?nm is newly observed in ZnS:Mn,Eu phosphors. The emission is related to Eu{sup 2+} doping but only appears at certain Eu{sup 2+} concentrations. It is found that the intensity of the 420?nm violet fluorescence is X-ray does-dependent, while the red fluorescence of 583?nm is not. The ratio of fluorescence intensities at 420?nm and 583?nm has been monitored as a function of X-ray doses that exposed upon the ZnS:Mn,Eu phosphors. Empirical formulas are provided to estimate the doses of applied X-ray irradiation. Finally, possible mechanisms of X-ray irradiation induced fluorescence quenching are discussed. The intense 420?nm emission not only provides a violet light for solid state lighting but also offers a very sensitive method for radiation detection.

  9. [Several conditions of formation and isolation of violet pigment from culture fluid of Nocardia fructiferi var. ristomycin].

    PubMed

    Toropova, E G; Egorov, N S; Tkhaker, V

    1983-11-01

    A new water-soluble photochromogenic fluorescent violet pigment with the indicator properties was isolated from the culture fluid of Nocardia fructiferi var. ristomycini, strain 76. By its solubility and mobility in various solvent systems and by the absorption spectrum the new pigment is close but not identical to such a pigment as rubrocyanin. The presence of microelements, i.e. iron and magnesium in the medium was shown to be necessary for production of violet pigment. PMID:6651270

  10. Dye molecules in electrolytes: new approach for suppression of dye-desorption in dye-sensitized solar cells

    PubMed Central

    Heo, Nansra; Jun, Yongseok; Park, Jong Hyeok

    2013-01-01

    The widespread commercialization of dye-sensitized solar cells remains limited because of the poor long-term stability. We report on the influence of dye-molecules added in liquid electrolyte on long-term stability of dye-sensitized solar cells. Dye-desorption from the TiO2 surface during long-term cycling is one of the decisive factors that degrade photocurrent densities of devices which in turn determine the efficiencies of the devices. For the first time, desorption of dye from the TiO2 surface could be suppressed by controlling thermodynamic equilibrium; by addition of dye molecules in the electrolyte. The dye molecules in the electrolyte can suppress the driving forces for the adsorbed dye molecules to be desorbed from TiO2 nanoparticles. As a result, highly enhanced device stabilities were achieved due to the reduction of dye-desorption although there was a little decrease in the initial efficiencies.

  11. Development of distributed feedback dye lasers for generation of high-power 193 nm excimer laser short pulses

    Microsoft Academic Search

    Yifeng Cui

    1993-01-01

    The combination of picosecond dye lasers, nonlinear mixing in crystals, and excimer amplifiers offers an attractive way to generate intense diffraction-limited pulses throughout the ultraviolet region. However, it is difficult to generate 193 nm seed pulses because this wavelength cannot be obtained by second harmonic generation method in any known crystals. The thesis will describe a laser system which efficiently

  12. Dye laser amplifier including a dye cell contained within a support vessel

    DOEpatents

    Davin, James (Gilroy, CA)

    1992-01-01

    A large (high flow rate) dye laser amplifier in which a continous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of greater than 30 gallons/minute at a static pressure greater than 150 pounds/square inch and a specifically designed support vessel for containing the dye cell.

  13. High efficiency cholesteric liquid crystal lasers with an external stable resonator

    E-print Network

    Richardson, Martin C.

    chiral nematic liquid crystals as a one-dimensional photonic stopband crystal: experiment and theoryHigh efficiency cholesteric liquid crystal lasers with an external stable resonator Hamidreza cholesteric liquid crystal (CLC) laser performance is demonstrated by utilizing a binary-dye mixture (with 62

  14. Electronic structure measurements of metal-organic solar cell dyes using x-ray absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Johnson, Phillip S.

    The focus of this thesis is twofold: to report the results of X-ray absorption studies of metal-organic dye molecules for dye-sensitized solar cells and to provide a basic training manual on X-ray absorption spectroscopy techniques and data analysis. The purpose of our research on solar cell dyes is to work toward an understanding of the factors influencing the electronic structure of the dye: the choice of the metal, its oxidation state, ligands, and cage structure. First we study the effect of replacing Ru in several common dye structures by Fe. First-principles calculations and X-ray absorption spectroscopy at the C 1s and N 1s edges are combined to investigate transition metal dyes in octahedral and square planar N cages. Octahedral molecules are found to have a downward shift in the N 1s-to-pi* transition energy and an upward shift in C 1s-to-pi* transition energy when Ru is replaced by Fe, explained by an extra transfer of negative charge from Fe to the N ligands compared to Ru. For the square planar molecules, the behavior is more complex because of the influence of axial ligands and oxidation state. Next the crystal field parameters for a series of phthalocyanine and porphyrins dyes are systematically determined using density functional calculations and atomic multiplet calculations with polarization-dependent X-ray absorption spectra. The polarization dependence of the spectra provides information on orbital symmetries which ensures the determination of the crystal field parameters is unique. A uniform downward scaling of the calculated crystal field parameters by 5-30% is found to be necessary to best fit the spectra. This work is a part of the ongoing effort to design and test new solar cell dyes. Replacing the rare metal Ru with abundant metals like Fe would be a significant advance for dye-sensitized solar cells. Understanding the effects of changing the metal centers in these dyes in terms of optical absorption, charge transfer, and electronic structure enables the systematic design of new dyes using less expensive materials.

  15. Metachromasy in clay mineral systems

    Microsoft Academic Search

    C. Dobrogowska; L. G. Hepler; D. K. Ghosh; Sh. Yariv

    1991-01-01

    Adsorption of the metachromic (colour depends on concentration) cationic dyes crystal violet (CV) and ethyl violet (EV) by Na-kaolinite and Na-montmorillonite has been studied by visible spectroscopy and titration calorimetry. In the kaolinite system, metachromasy stems from association of the dye cations on the external surface of the clay. Enthalpies of adsorption at small dye\\/clay ratios are ?3.5 and ?3.8

  16. Novel fluoranthene dyes for efficient dye-sensitized solar cells

    Microsoft Academic Search

    Xuemei Ma; Wenjun Wu; Qiong Zhang; Fuling Guo; Fanshun Meng; Jianli Hua

    2009-01-01

    Three, novel, fluoranthene-based dyes, 2-cyano-3-(5-(7,12-diphenylbenzo[k]fluoranthen-3-yl)thiophen-2-yl)acrylic acid, 2-(5-((5-(7,12-diphenylben-zo[k]fluoranthen-3-yl)thiophen-2-yl)methylene)-4-oxo-2-thioxothiazolidin-3-yl)acetic acid and 2-cyano-3-(4-(2-(7,12-diphenylbenzo[k]fluoranthen-3-yl)ethynyl) phenyl) acrylic acid, were synthesized for application as sensitizers in dye-sensitized solar cells. In each dye, the 7,12-diphenyl-benzo[k]fluoranthene moiety acted as electron donor with phenyl and thiophene units as electron spacers and carboxylic acid as electron acceptor. Tuning of the HOMO and LUMO energy levels was conveniently accomplished by changing

  17. Dyes as tracers for vadose zone hydrology

    NASA Astrophysics Data System (ADS)

    Flury, Markus; Wai, Nu Nu

    2003-03-01

    Dyes are important tracers to investigate subsurface water movement. For more than a century, dye tracers have provided clues about the hydrological cycle as well as flow and transport processes in the subsurface. Groundwater contamination often originates in the vadose zone. Agrochemicals applied to the soil surface, toxic compounds accidentally spilled by human activities, and contaminants released from waste repositories leach through the vadose zone and can ultimately pollute groundwater resources. Dyes are an important tool to assess flow pathways of such contaminants. This review compiles information on dyes used as hydrological tracers, with particular emphasis on vadose zone hydrology. We summarize briefly different human-applied tracers, including nondye tracers. We then provide a historical sketch of the use of dyes as tracers and describe newer developments in visualization and quantification of tracer experiments. Relevant chemical properties of dyes used as tracers are discussed and illustrated with dye intermediates and selected dye tracers. The types of dyes used as tracers in subsurface hydrology are summarized, and recommendations are made regarding the use of dye tracers. The review concludes with a toxicological assessment of dyes used as hydrological tracers. Many different dyes have been proposed as tracers for water movement in the subsurface. All of these compounds, however, are to some degree retarded by the subsurface medium. Nevertheless, dyes are useful tracers to visualize flow pathways.

  18. Spectroscopic properties of phthalocyanine dyes for optical recording medium

    NASA Astrophysics Data System (ADS)

    Shen, Shuyin; Liu, Kai; Xu, Huijun; Gu, Donghong; Tang, Fulong; Chen, Qiying

    1996-09-01

    Phthalocyanine dyes with various central metal atoms and different substituents showing improved spectroscopic properties to match the output of GaAs diode-laser have been synthesized. Smooth thin films have been prepared by spin- coating technique. Solvent-vapor induced crystallization of VOPc(OC3H7)4 has also been studied. The results showed that the VOPc(OC3H7)4 primarily deposited on glass substrate as an amorphous form. However, the dyes were changed to crystalline form by exposure to appropriate solvent vapors. The polymorphs of the VOPc(OC3H7)4 were investigated by visible absorption and IR spectroscopy, X-ray diffraction and high resolution electron microscopy. The optical recording performances of the thin films were also reported.

  19. Ordered dye-functionalized TiO2 nanostructures for photoelectrochemical applications

    Microsoft Academic Search

    Tammy P. Chou; Steven J. Limmer; Guozhong Cao

    2003-01-01

    Nanomaterials are advantageous for photoelectrochemical solar cell devices for high efficient conversion of light to electrical power due to its large surface area at which photoelectrochemical processes take place. One of the current solar cell systems utilizes dye-functionalized mesoporous titania films that consist of an interconnected network of nanometer-sized crystals. This type of structure imparts a large surface area for

  20. Anaerobic\\/aerobic treatment of selected azo dyes in wastewater

    Microsoft Academic Search

    S. Seshadri; P. L. Bishop; A. M. Agha

    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

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

    E-print Network

    McGehee, Michael

    High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells Brian E, TT1, to increase the overall power conversion efficiency of a dye-sensitized solar cell (DSC) from 3 be efficiently implemented in optimized dye-sensitized solar cells, but also highlights the need to design highly

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

    E-print Network

    McGehee, Michael

    Increased light harvesting in dye-sensitized solar cells with energy relay dyes Brian E. Hardin1 factors. However, dye-sensitized solar cells do not completely absorb all of the photons from the visible pathway to develop more efficient dye-sensitized solar cells. D ye-sensitized solar cells (DSCs) work

  3. New fluoranthene-based cyanine dye for dye-sensitized solar cells

    Microsoft Academic Search

    Wenjun Wu; Fuling Guo; Jing Li; Jinxiang He; Jianli Hua

    2010-01-01

    In this paper, a new fluoranthene-based unsymmetrical organic cyanine dye I and the corresponding cyanine dye II containing ethynyl unit for the purpose of comparison were designed and synthesized as sensitizers for the application in dye-sensitized solar cells (DSSCs). The absorption spectra, electrochemical and photovoltaic properties of I and II were extensively investigated. The DSSCs based on the fluoranthene dye

  4. TEXTILE DYEING WASTEWATERS: CHARACTERIZATION AND TREATMENT

    EPA Science Inventory

    The report gives results of an examination of the biological, chemical, and physical treatability of wastewaters from selected typical dye baths. Twenty systems providing a broad cross section of dye classes, fibers, and application techniques, were examined. Wastes, produced usi...

  5. Jupiter's Belt-Zone Boundary in Near-Infrared and Violet Light

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Mosaics of a belt-zone boundary near Jupiter's equator in violet (top panel) and near-infrared (bottom panel) light. The four images that make up each of these mosaics were taken within a few minutes of each other. Sunlight at 757 nanometers (near-infrared) penetrates deep into Jupiter's troposphere before being absorbed or scattered by clouds to the Galileo spacecraft. This wavelength reveals the features of the lower visible cloud deck. Sunlight at 415 nanometers (violet) is a scattered or absorbed to varying degrees in different parts of Jupiter's atmosphere depending on the types and concentrations of cloud particles and chemicals that color Jupiter's atmosphere. The near-infrared mosaic primarily shows cloud features. The violet mosaic has three distinct regions: it is brightest at the latitude of the jet (horizontally across the center of the mosaic), moderately bright north of the jet, and dark and patchy south of the jet.

    North is at the top. The mosaic covers latitudes -13 to +3 degrees and is centered at longitude 282 degrees West. The smallest resolved features are tens of kilometers in size. These images were taken on November 5th, 1996, at a range of 1.2 million kilometers by the Solid State Imaging system aboard NASA's Galileo spacecraft.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  6. Recycling of agricultural solid waste, coir pith: removal of anions, heavy metals, organics and dyes from water by adsorption onto ZnCl2 activated coir pith carbon.

    PubMed

    Namasivayam, C; Sangeetha, D

    2006-07-31

    The abundant lignocellulosic agricultural waste, coir pith is used to develop ZnCl(2) activated carbon and applied to the removal of toxic anions, heavy metals, organic compounds and dyes from water. Sorption of inorganic anions such as nitrate, thiocyanate, selenite, chromium(VI), vanadium(V), sulfate, molybdate, phosphate and heavy metals such as nickel(II) and mercury(II) has been studied. Removal of organics such as resorcinol, 4-nitrophenol, catechol, bisphenol A, 2-aminophenol, quinol, O-cresol, phenol and 2-chlorophenol has also been investigated. Uptake of acidic dyes such as acid brilliant blue, acid violet, basic dyes such as methylene blue, rhodamine B, direct dyes such as direct red 12B, congo red and reactive dyes such as procion red, procion orange were also examined to assess the possible use of the adsorbent for the treatment of contaminated ground water. Favorable conditions for maximum removal of all adsorbates at the adsorbate concentration of 20 mg/L were used. Results show that ZnCl(2) activated coir pith carbon is effective for the removal of toxic pollutants from water. PMID:16406295

  7. Modeling gallium-nitride-based violet lasers for data storage of information technology

    NASA Astrophysics Data System (ADS)

    Shih, Meng-Mu

    2012-03-01

    This work shows the process of computing coupling coefficients of first-order distributed feedback (DFB) metalsemiconductor quantum-well lasers which emit the violet light for data storage of information technology. The optical waveguide structure for such a laser has semiconductor layers and a built-in metal grating layer. The interface between the metal layer and its neighboring semiconductor layer has a sinusoidal corrugation functioning as the grating. To compute the coupling coefficient of the metal-grating waveguide, a model is constructed by Floquet-Bloch formalism (FB). Ray optics technique (RO) is also used to calculate the coupling coefficients. These two methods have close results.

  8. Extreme ultra-violet movie camera for imaging microsecond time scale magnetic reconnection.

    PubMed

    Chai, Kil-Byoung; Bellan, Paul M

    2013-12-01

    An ultra-fast extreme ultra-violet (EUV) movie camera has been developed for imaging magnetic reconnection in the Caltech spheromak/astrophysical jet experiment. The camera consists of a broadband Mo:Si multilayer mirror, a fast decaying YAG:Ce scintillator, a visible light block, and a high-speed visible light CCD camera. The camera can capture EUV images as fast as 3.3 × 10(6) frames per second with 0.5 cm spatial resolution. The spectral range is from 20 eV to 60 eV. EUV images reveal strong, transient, highly localized bursts of EUV radiation when magnetic reconnection occurs. PMID:24387431

  9. Feasibility of solar-pumped dye lasers

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1987-01-01

    Dye laser gains were measured at various pump-beam irradiances on a dye cell in order to evaluate the feasibility of solar pumping. Rhodamine 6G dye was considered as a candidate for the solar-pumped laser because of its high utilization of the solar spectrum and high quantum efficiency. Measurements show that a solar concentration of 20,000 is required to reach the threshold of the dye.

  10. Industrial hygiene concerns of laser dyes

    Microsoft Academic Search

    1990-01-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye`s toxicity or mutagenicity\\/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity\\/carcinogenicity of the solvent

  11. Optofluidic ring resonator dye lasers

    NASA Astrophysics Data System (ADS)

    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.

  12. Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration

    DOEpatents

    Davin, J.

    1992-12-01

    A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of for example 30 gallons/minute, a specifically designed support vessel for containing the dye cell and a screen device for insuring that the dye stream passes into the dye cell in a substantially turbulent free, stagnation-free manner. 9 figs.

  13. Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration

    DOEpatents

    Davin, James (Gilroy, CA)

    1992-01-01

    A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of for example 30 gallons/minute, a specifically designed support vessel for containing the dye cell and a screen device for insuring that the dye stream passes into the dye cell in a substantially turbulent free, stagnation-free manner.

  14. A new method for photodynamic therapy of melanotic melanoma -- effects of depigmentation with violet light photodynamic therapy.

    PubMed

    Ma, Li-Wei; Nielsen, Kristian Pagh; Iani, Vladimir; Moan, Johan

    2007-01-01

    Melanotic melanomas have a poor response to photodynamic therapy (PDT). The reason for this is that melanin absorbs light over the entire wavelength region used for PDT (400-750 nm). Photobleaching of melanin is an approach to overcome this obstacle. In the present work, reflectance spectroscopy was applied to study depigmentation of human and murine skin with different melanin contents, and effects induced by PDT with topical application of methyl 5-aminolevulinate (MAL) on B16F10 melanotic melanomas transplanted to nude mice. Depigmentation and inhibition of tumor growth after violet light (420 nm) exposure, red light (634 nm) exposure, and combinations of both were studied. Reflectance spectroscopy was suitable for evaluation of the pigmentation of both human and murine skin. Skin depigmentation leads to increase in reflectance. PDT with violet light bleached some of the melanin in the skin above the B16F10 melanomas, and possibly also in the upper part of the melanomas. This resulted in a larger growth inhibition of tumors first given PDT with violet light and then with red light compared to treatments using the reverse order of illumination, namely, red light before violet light. It is concluded that violet light PDT can bleach melanin in melanotic tumors and therefore increase their sensitivity to red light PDT. This finding indicates a new PDT modality that can be further developed for treatment of superficial melanotic melanomas and possibly other diseases where pigmentation is a problem. PMID:18197832

  15. Industrial hygiene concerns of laser dyes

    Microsoft Academic Search

    1990-01-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye's toxicity or mutagenicity\\/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity\\/carcinogenicity of the solvent

  16. Degradation of Congo Red Dye by Ozonation

    Microsoft Academic Search

    Arthit Neramittagapong

    The purpose of this study was to investigate the degradation of azo dye in synthetic wastewater by ozonation and to optimize the reaction parameters such as pH, time and type of catalysts which influence the efficiencies of color and COD removal. Congo red dye was selected as model pollutant. Catalytic and non-catalytic ozonation of Congo red dye were carried out

  17. Dye-Sensitized Cuprrous Iodide Photocathode

    NASA Astrophysics Data System (ADS)

    Tennakone, K.; Fernando, C. A. N.; Dewasurendra, M.; Kariappert, M. S.

    1987-04-01

    Copper plates coated with cuprous iodide (p-type semiconductor) are found to adsorb iodides of cationic dyes extremely well. Photocurrent efficiency and stability of dye-sensitized CuI photocathodes in aqueous KI+I2 are studied. Deposition of trace quantities of platinum on top of the dye layer is found to increase the stability and the photocurrent quantum efficiency.

  18. Modeling the efficiency of Frster resonant energy transfer from energy relay dyes in dye-

    E-print Network

    McGehee, Michael

    of dye sensitized solar cells. In this design, unattached relay dyes absorb the high energy photons-Efficiency Solar Cell Based on Dye-Sensitized Colloidal TiO2 Films," Nature 353(6346), 737­740 (1991). 2. M. K in dye-sensitized solar cells with energy relay dyes," Nat. Photonics 3(7), 406­411 (2009). 4. P. R. F

  19. Theory of pulsed dye lasers including dye-molecule rotational relaxation

    Microsoft Academic Search

    Roger A. Haas; Mark D. Rotter

    1991-01-01

    In this paper a phenomenological semiclassical theory of pulsed-laser-pumped dye-laser light amplifiers is presented. The theory accounts for the broadband radiation absorption and emission characteristics of dye molecules in liquid solvents. Dye-molecule fluorescence, vibrational, rotational, and electric polarization relaxation processes are represented by phenomenological relaxation rates. In general, it is found that due to dye-molecule rotational relaxation the laser-pumped dye

  20. Novel iminocoumarin dyes as photosensitizers for dye-sensitized solar cell

    Microsoft Academic Search

    Velappan Kandavelu; Hsin-Sian Huang; Jia-Liang Jian; Thomas C.-K. Yang; Kun-Li Wang; Sheng-Tung Huang

    2009-01-01

    Novel iminocoumarin dyes (2a–c and 3a–c) having carboxyl and hydroxyl anchoring groups onto the dyes skeletons have been designed and synthesized for the application of dye-sensitized nanocrystalline TiO2 solar cells (DSSCs). The photophysical and electrochemical studies showed that these iminocoumarin dyes are suitable as light harvesting sensitizers in DSSC application. The dyes having carboxyl and hydroxyl anchoring groups (2a–c) showed

  1. Efficient dye-sensitized solar cells with triarylamine organic dyes featuring functionalized-truxene unit

    Microsoft Academic Search

    Mao Liang; Meng Lu; Qi-Lin Wang; Wei-Yi Chen; Hong-Yu Han; Zhe Sun; Song Xue

    2011-01-01

    Four triarylamine organic dyes featuring functionalized-truxene unit (MXD1–4) have been designed, synthesized, and characterized. It was found that these dyes favored light harvesting, prevented dye aggregation and suppressed the dark current significantly in dye-sensitized solar cells (DSSCs), leading to enhanced performance compared to the corresponding triphenylamine dye. As a result of retarding charge recombination benefiting from the steric hindrance of

  2. Fluorine-doped zinc oxide thin films: influence of precursor flow rate on violet luminescence

    NASA Astrophysics Data System (ADS)

    Muthukumar, Anusha; Dakshnamoorthy, Arivuoli

    2015-06-01

    Fluorine-doped zinc oxide (FZO) thin films were deposited by the aerosol-assisted chemical vapor deposition method with variable precursor flow rates (0.5-2.5 ml/min). X-ray diffraction patterns revealed the polycrystalline hexagonal wurtzite structure of the derived FZO nanocrystalline thin films. Extensive crystallinity analysis of the film deposited at 1 ml/min was done by grazing incidence X-ray diffraction. Field emission scanning electron microscope images apparent the gradual evolution from spherical grains and hexagonal platelet like surface morphology with increased flow rate. Optical transparency and photoluminescence (PL) are strongly influenced by flow rate. PL intensity and transparency increase with decreased flow rate. The optical bandgap was tuned significantly by increase in flow rate and especially tuned the PL emission from violet to UV. High intense violet PL observed at flow rate of 1 ml/min and radiative transition of electrons from zinc vacancies level to the conduction band were found. Crystallinity, growth rate and roughness increase with increased flow rate.

  3. Industrial hygiene concerns of laser dyes

    SciTech Connect

    Miller, G.

    1990-11-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye`s toxicity or mutagenicity/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity/carcinogenicity of the solvent used. Working from this information, we have proposed three control classes -- limited, moderate, and strict -- for work performed with dyes in each class. This paper describes the considerations that went into preparing our guidelines and summarizes the precautions themselves.

  4. Dye-sensitized solar cells

    Microsoft Academic Search

    Michael Grätzel

    2003-01-01

    The dye-sensitized solar cells (DSC) provides a technically and economically credible alternative concept to present day p–n junction photovoltaic devices. In contrast to the conventional systems where the semiconductor assume both the task of light absorption and charge carrier transport the two functions are separated here. Light is absorbed by a sensitizer, which is anchored to the surface of a

  5. The chromonic phases of dyes

    Microsoft Academic Search

    T. K. Attwood; J. E. Lydon; F. Jones

    1986-01-01

    It has been shown that the lyotropic liquid-crystalline phases formed by certain dyes are structurally analogous to the chromonic N and M liquid-crystalline phases previously thought to be unique to certain anti-asthmatic\\/anti-allergic drugs. We suspect that these two groups of compounds will prove to be representatives of a large new class of mesogenic materials.

  6. Red, violet and upconversion luminescence of Eu/Sm codoped sol gel SiO2-TiO2

    NASA Astrophysics Data System (ADS)

    Azzouz, I. M.; Klein, Lisa C.

    2012-12-01

    Rare earth (Eu/Sm) doped silica-titania composite systems were sensitized by sol-gel method in solid and powder forms. The crystalline phase has been identified for the annealed samples at 1000 °C by X-ray diffraction (XRD). The bonding formation of the host matrix was examined by Fourier transform infrared (FTIR). The fingerprint transition lines of Eu3+ ions, with the main emission line at 616 nm, are recorded for the samples. Improvement in Eu3+ luminescence has been recorded by adding Sm3+ and by samples. Violet emission is observed under UV irradiation. Violet-blue upconversion luminescence is recorded at room temperature.

  7. Improving optical absorptivity of natural dyes for fabrication of efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hemmatzadeh, Reza; Mohammadi, Ahmad

    2013-11-01

    Efficient and cheap dye-sensitized solar cells (DSSCs) were fabricated using natural dyes from Pastinaca sativa and Beta vulgaris. Natural dyes are environmentally and economically superior to ruthenium-based dyes because they are nontoxic and cheap. However, the conversion efficiency of dye-sensitized solar cells based on natural dyes is low. One way to improve the DSSC performance is to enhance the absorptivity of extracted dyes. We investigated the influence of various factors in the extraction process, such as utilization of different extraction approaches, the acidity of extraction solvent, and different compounds of solvents on the optical absorption spectra. It was found that we could considerably enhance the optical absorptivity of dye and consequently the performance of DSSC by choosing a proper mixture of ethanol and water for extracting solvent and also the acidity of dye solution.

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

    NASA Technical Reports Server (NTRS)

    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.

  9. Characteristics of a broadband dye laser using Pyrromethene and Rhodamine dyes.

    PubMed

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

    2011-02-20

    A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full width at half-maximum from 592 to 610?nm was created for the use in a dual-pump broadband coherent anti-Stokes Raman spectroscopy (CARS) system called width increased dual-pump enhanced CARS (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 was 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 and Pyrromethene dyes 597 and 650, as well as mixtures of these dyes. PMID:21343970

  10. Light Controlled Capillarity of Liquid Crystals on Photo Anisotropic Surfaces

    Microsoft Academic Search

    Guillaume Goubert; Tigran V. Galstian

    2010-01-01

    We report the observation and experimental study of an anisotropic photo controlled capillarity effect in liquid crystal cells. The photo sensitive substrates of the cell are composed of reactive mesogen host that is doped by guest azobenzene dye. We first describe the study of photo induced phenomena in those substrates, then the capillary propagation of the liquid crystal that is

  11. Sensitivity enhancement in photonic crystal slab Mohamed El Beheiry,1

    E-print Network

    Fan, Shanhui

    by quality factor reductions, which are common to fabricated photonic crystal nano- structures. Finally, we in a microfluidic device. ©2010 Optical Society of America OCIS codes: (050.5298) Photonic crystals; (130-Jaricot, R. Nitschke, and T. Nann, "Quantum dots versus organic dyes as fluorescent labels," Nat. Methods 5

  12. Treatment of Azo Dye-Containing Wastewater Using Integrated Processes

    Microsoft Academic Search

    Xujie Lu; Rongrong Liu

    \\u000a Azo dyes are the most widely used dyes in textile industry. During the dyeing process, the degree of exhaustion of dyes is\\u000a never complete, resulting in azo dye-containing effluents. The biodegradation of azo dyes is difficult due to their complex\\u000a structure and synthetic nature. The removal of azo dyes from industry effluents is desirable not only for aesthetic reasons\\u000a but

  13. DCM-based organic dyes with electron donating groups for dye-sensitized solar cells.

    PubMed

    Kim, Joo Young; Yoon, Seung Soo; Kim, Young Sik

    2014-07-01

    Herein, 4-(dicyanomethylene)-2-methyl-6-[p-(dimethylamino)styryl]-4H-pyran (DCM)-based dyes with electron donating groups were designed and their electronic and optical properties were investigated theoretically for dye-sensitized solar cells (DSSCs). Among the dyes, the D1 and D2 dyes were composed of single electron donating group and the D3 and D4 dyes composed of dual donating group. We performed DFT/TDDFT calculations to get insight into the factors responsible for photovoltaic properties as dye sensitizers. It showed that all the dyes in this work are available as dye sensitizers from the energy consideration compared to TiO2 electrode and iodide electrolyte. It also showed that the D3 and D4 dyes produced additional absorption bands by the introduction of dual donor in absorption spectra and the absorption band of the D4 dye is more red-shifted than that of the D3 dye. It is attributed to the fact that the M2 (a coumarin derivative) moiety with stronger electron withdrawing ability stabilized its LUMO level. In terms of molar extinction coefficient and panchromatic feature, we suggest that the D4 dye would show better performance than other dyes in the present study as a dye sensitizer for DSSCs. PMID:24758003

  14. Time-resolved photoelectrochemical measurements and photovoltaic efficiency of electrochemically self-assembled ZnO-dye electrodes

    NASA Astrophysics Data System (ADS)

    Schlettwein, Derck; Oekermann, Torsten; Tsukasa, Yoshida; Sugiura, Takashi; Minoura, Hideki; Woehrle, Dieter

    2002-02-01

    Dye-modified ZnO thin films were prepared by electrochemically induced crystallization from aqueous mixtures of zinc nitrate and water-soluble dyes. A direct crystallization of semiconductor/ dye composites without heat treatment is seen as a significant advantage of this method. Moreover, characterization of these materials has revealed ordered growth of ZnO crystallites as well as formation of ordered dye assemblies, thus characterizing this method as electrochemical self-assembly. The photoelectrochemical properties of these unique ZnO-dye thin film electrodes were investigated in photocurrent transient measurements in the ms-regime and by steady- state voltammetric measurements. Two sets of electrodes are discussed, employing either metal complexes of tetrasulfophthalocyanines (TSPcMt; Mt = Zn, Al, Si) or the xanthene dye Eosin Y. For aggregates of TSPcMt on ZnO, efficient charge-transfer to the electrolyte is found, leading to low surface charging and low surface recombination of photogenerated holes with electrons from the ZnO, at however, rather low injection efficiencies of electrons into the conduction band of ZnO. This efficiency was higher for adsorbed monomers of TSPcMt leading to a considerably higher quantum efficiency of the photocurrent in spite of increased surface charging and recombination of holes. Higher photocurrents were observed for ZnO sensitized with monomers of Eosin Y caused by both, efficient electron transfer from the dye to ZnO as well as hole transfer from the dye to the electrolyte. Not only dye molecules which were directly accessible from the electrolyte, but also those which were enclosed within matrix cavities proved to be photoelectrochemically active.

  15. Infrared liquid crystal polymer micropolarizer.

    PubMed

    Hsu, Wei-Liang; Balakrishnan, Kaushik; Ibn-Elhaj, Mohammed; Pau, Stanley

    2014-08-10

    The ability to create arbitrary patterned linear and circular infrared (IR) liquid crystal polymer (LCP) polarizers is demonstrated. The operating wavelength of the thin-film polarizer ranges from 700 to 4200 nm. The linear micropolarizer is fabricated using IR dichroic dye as a guest in LCP host with feature size as small as 4 ?m. The circular micropolarizer is fabricated using cholesteric LCPs with feature size as small as 6.2 ?m. PMID:25320936

  16. Studies on decolorization of reactive blue 19 textile dye by Coprinus plicatilis

    PubMed Central

    2014-01-01

    Background Studies were carried on the decolorization of the textile dye reactive blue 19 (RB 19) by a novel isolate of Coprinus plicatilis (C. plicatilis) fungi. We describe an in vitro optimization process for decolorization and its behavior under different conditions of carbon and nitrogen sources, pH, temperature and substrate concentration. Results The optimal conditions for decolorization were obtained in media containing intermediate concentrations of ammonium oxalate and glucose (10 g/L) as nitrogen and carbon sources, respectively, at 26°C and pH?=?5.5. Maximum decolorization efficiency against RB 19 achieved in this study was around 99%. Ultra-violet and visible (UV-vis) spectrophotometric analyses, before and after decolorization, suggest that decolorization was due to biodegradation. Conclusions This effect was associated with laccase enzyme displaying good tolerance to a wide range of pH values, salt concentrations and temperatures, suggesting a potential role for this organism in the remediation of real dye containing effluents. In conclusion, laccase activity in C. plicatilis was firstly described in this study. PMID:24565535

  17. Field response of some asparagus varieties to rust, Fusarium crown root rot, and violet root rot.

    PubMed

    Fiume, F; Fiume, G

    2003-01-01

    Research was carried out to evaluate the behaviour of some asparagus genotypes against three most important fungal diseases: 1) asparagus rust caused by Puccinia asparagi D.C.; 2) Fusarium crown and root rot caused by Fusarium oxysporum (Schlecht.) f.sp. asparagi (Cohen & Heald) and Fusarium proliferatum (Matstush.) Nirenberg; 3) violet root rot caused by Rhizoctonia violacea Tul. The object of this research was also to found an eventual correlation between the plant susceptibility to asparagus rust and the sensibility to Fusarium crown root rot and violet root rot attacks. Resistant genotypes to rust should be less susceptible to attacks from F. oxysporum f.sp. asparagi, F. proliferatum and R. violacea, a fungal complex causing the plant decline. Asparagus genotypes were compared in a randomized complete block experiment design, replicated four times, in order to search that ones showing the best behaviour to escape the diseases. Phytopathological observations were carried out on November when the control plots showed 100% infected plants. The pathogens were isolated and identified. The diseased plants were registered. According to symptom evaluation scales, all the plants were grouped into infection classes, calculating frequency and McKinney index. Wishing to learn something about the infection trend of F. oxysporum f.sp. asparagi or R. violacea in relation to P. asparagi attack, the relative curvilinear regressions were calculated. The Italian cultivars "Marte" and "Grande" showed significantly the best behaviour in terms of resistance to asparagus rust, exhibiting 37% and 42% of diseased plants. The McKinney index was 9.1% and 15.6%, respectively. The susceptible plots showed 100% of infected plants and different McKinney index: 46% for "Eros", about 60% for "H 519", "Atlas" and "Golia", over 70% for the remainder. "Marte" and "Grande" showed good tolerance to F. oxysporum f.sp. asparagi and to R. violacea exhibiting up to 100% of healthy plants. The regression between plants affected by asparagus rust and those diseased by Fusarium crown root rot showed a linear equation with a regression coefficient b = 1.186 and a correlation coefficient R2 = 0.98. The regression between infection caused by rust and that caused by violet root rot exhibited a regression coefficient b = 1.03 and a coefficient of correlation R2 = 0.9. "Marte" and "Grande" exhibited the best behaviour against the rust attacks. Plants without rust were tolerant to pathogens causing plant decline. PMID:15151301

  18. Visualization of regional cerebrospinal fluid flow with a dye injection technique in focal arachnoid pathologies.

    PubMed

    Yamaguchi, Satoshi; Hida, Kazutoshi; Takeda, Masaaki; Mitsuhara, Takafumi; Morishige, Mizuki; Yamada, Naoto; Kurisu, Kaoru

    2015-05-01

    Surgical lysis of the thickened arachnoid membrane is the first choice of treatment in spinal arachnoid pathologies that cause flow disturbances or blockage of CSF. However, it is important to consider that while extensive lysis of the arachnoid may temporarily provide a wide pathway for CSF, an extensive lytic procedure may later cause secondary adhesion. Thus, it is ideal for the proper extent of the arachnoid lysis to be determined after careful analysis of regional CSF flow. The authors report their limited experience with intraoperative visualization of CSF flow in spinal arachnoid pathologies. Two patients with a dorsal arachnoid web (DAW) with cervical syringomyelia and 1 patient with focal adhesive arachnoiditis causing edema of the spinal cord were surgically treated at the authors' institution between 2007 and 2013. In all cases, the presence of a DAW or focal adhesive arachnoiditis was suspected from the findings on MRI, namely 1) an indentation on the upper thoracic spinal cord and 2) syringomyelia and/or edema of the spinal cord above the indentation. Exploratory surgery disclosed a transversely thickened arachnoid septum on the dorsal side of the indented cord. To prove blockage of the CSF by the septum and to decide on the extent of arachnoid lysis, regional CSF flow around the arachnoid septum was visualized by subarachnoid injection of gentian violet solution close to the web. Injected dye stagnated just close to the arachnoid septum in all cases, and these findings documented CSF blockage by the septum. In 2 cases, a 2-minute observation showed that the injected dye stayed close to the web without diffusion. The authors performed not only resection of the web itself but also lysis of the thickened arachnoid on both sides of the spinal cord to make a CSF pathway on the ventral side. In the third case, the dye stagnated close to the web at first but then diffused through the nerve root to the ventral CSF space. The lysis procedure was completed after exclusive removal of the dorsal web. Postoperative MR images confirmed reduction of the syrinx and/or improvement of the edema in all cases, suggesting that the extent of arachnoid lysis was optimal in each case. No adverse effect was observed after subarachnoid injection of gentian violet. The authors believe that their technique of visualizing regional CSF flow will be helpful to decide the optimal extent of lysis in some local arachnoid pathologies. PMID:25679234

  19. One-dimensional birefringent photonic crystal laser

    Microsoft Academic Search

    Sun Woong Kim; Seung Seok Oh; Jin Ho Park; Eun Ha Choi; Yoon Ho Seo; Guang Sup Cho

    2008-01-01

    We studied the polarized laser emission from an anisotropic one-dimensional (1D) birefringent photonic crystal (PC) laser. An active medium layer, which consisted of an epoxy resin doped with fluorescent dye, was sandwiched between two anisotropic 1D PC films. It was shown that efficient laser emissions were generated by optical pumping at relatively low lasing thresholds. The wavelengths of the emitted

  20. Enhanced biosensing using photonic crystal fibers

    Microsoft Academic Search

    M. T. Myaing; J. Y. Ye; T. B. Norris; T. Thomas; A. Kotylar; A. Patri; W. J. Wadsworth; R. M. Percival; G. Bouwmans; J. C. Knight; P.St.J. Russell

    2003-01-01

    A double-clad photonic crystal fiber was used to improve detection efficiency over a regular single mode fiber in a two-photon fluorescence detection scheme where the dye was excited and the fluorescence was detected back through the same fiber.

  1. Two-Photon Absorption Spectrum of a Single Crystal Cyanine-like Honghua Hu,

    E-print Network

    Van Stryland, Eric

    Two-Photon Absorption Spectrum of a Single Crystal Cyanine-like Dye Honghua Hu, Dmitry A. Fishman Vegas, New Mexico 87701, United States *S Supporting Information ABSTRACT: The two-photon absorption (2PA) spectrum of an organic single crystal is reported. The crystal is grown by self

  2. Nano-fluidic dye laser

    E-print Network

    Gersborg-Hansen, M; Gersborg-Hansen, Morten; Kristensen, Anders

    2006-01-01

    This letter describes the design and operation of a single mode polymer-based nano-fluidic dye laser. The device relies on light-confinement in a nano-structured polymer film where an array of nano-fluidic channels is filled by capillary action with a liquid dye solution which has a refractive index lower than that of the polymer. In combination with a third order distributed feed-back (DFB) grating, formed by the array of nano-fluidic channels, this yields a low threshold for lasing. The laser is straight-forward to integrate on Lab-on-a-Chip micro-systems, e.g. for novel sensor concepts, where coherent, tunable light in the visible range is desired.

  3. 75 FR 62765 - Carbazole Violet Pigment 23 From India: Final Results of Antidumping Duty Changed-Circumstances...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-13

    ...Administration [A-533-838] Carbazole Violet Pigment 23 From India: Final Results of Antidumping...as amended (the Act), that Meghmani Pigments is the successor-in-interest to Alpanil...we preliminarily found that Meghmani Pigments is the successor-in-interest to...

  4. HPLC Determination and MS Confirmation of Malachite Green, Gentian Violet, and Their Leuco Metabolites in Catfish Muscle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Residues of malachite green (MG), gentian violet (GV), and their leuco metabolites in catfish muscle were individually determined by HPLC using visible and fluorescence detectors. This detection scheme obviated a PbO2 column that converts leuco forms to chromatic forms for visible detection, thus el...

  5. Electrospun mixed oxide photocatalysts to decompose dyes in water

    NASA Astrophysics Data System (ADS)

    Divya, Sherlyn

    In this work, four catalysts have been studied for their photocatalytic efficiency by testing each with methylene blue dye solution. Three catalysts were synthesized by the electrospinning method and then compared with the fourth commercially available catalyst for their photocatalytic activity. The basic metal oxide studied was titanium dioxide. Nanocomposite mats of pure titania, copper doped titania and copper doped degussa P25 titania, were synthesized using the electrospinning method. The pure titania and copper doped titania nanocomposites possessed the anatase phase which was obtained by annealing the as-spun nanocomposites at 4500C. All the catalysts were analyzed for their photocatalytic activity both under ultra-violet light and under visible light. The aim of this work was to synthesize titania photocatalysts, demonstrate their photocatalytic activity with methylene blue solution under UV-light and visible light and compare their activities with the commercial titanium dioxide (degussa P25). It is important to synthesize visible light active photocatalysts as these could be activated under a wide spectrum of natural sunlight unlike the degussa titanium dioxide. Doping was incorporated in order to narrow the band gap energy of the photocatalyst for achieving higher efficiency especially under visible light irradiation. The morphology and size of the synthesized photocatalysts were studied by characterizing them with Scanning Electron Microscopy, Energy Dispersive X-Ray Spectroscopy, Transmission Electron Microscopy and X-Ray Diffraction. The photocatalytic activity tests were carried out using UV-Vis Spectroscopy. It was found that the electrospun pure titania and copper doped titania fibers were activated under the visible light spectrum unlike the degussa titanium dioxide. The copper doped titania provided to be the most efficient photocatalyst under visible light radiation and the importance of this finding can be extended for treating industrial wastewaters by just exposing it to natural sunlight in the presence of this photocatalyst.

  6. Acylated anthocyanins from the blue-violet flowers of Anemone coronaria.

    PubMed

    Saito, Norio; Toki, Kenjiro; Moriyama, Hidekazu; Shigihara, Atsushi; Honda, Toshio

    2002-06-01

    Five polyacylated anthocyanins were isolated from blue-violet flowers of Anemone coronaria 'St. Brigid'. They were identified as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its demalonylated form, delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its cyanidin analog as well as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-(tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]. PMID:12031427

  7. Violet electroluminescence from p-GaN thin film/n-GaN nanowire homojunction

    NASA Astrophysics Data System (ADS)

    Ahn, Jaehui; Mastro, Michael A.; Hite, Jennifer; Eddy, Charles R.; Kim, Jihyun

    2010-03-01

    The difficulty associated with the precise positioning of nanowires has been one of the most significant issues hindering nanoelectronic integration. In this paper, we employed dielectrophoretic force to manipulate n-type GaN nano- and microwires onto a p-type GaN thin film to form a pristine p-n homojunction. The GaN wires were attracted to the n-type Ohmic metal in a direction parallel to the electric field, which was consistent with our simulation results. Violet electroluminescence emanated from the point of the n-GaN wire in contact with the p-GaN thin film. This p-n homojunction device displayed forward conduction above 6-9 V and current rectifying behavior down to a -20 V reverse bias. The current-voltage characteristics are distinctive of a p-n homojunction formed without deleterious damage or contamination.

  8. Bias Selectable Dual Band AlGaN Ultra-violet Detectors

    NASA Technical Reports Server (NTRS)

    Yan, Feng; Miko, Laddawan; Franz, David; Guan, Bing; Stahle, Carl M.

    2007-01-01

    Bias selectable dual band AlGaN ultra-violet (UV) detectors, which can separate UV-A and UV-B using one detector in the same pixel by bias switching, have been designed, fabricated and characterized. A two-terminal n-p-n photo-transistor-like structure was used. When a forward bias is applied between the top electrode and the bottom electrode, the detectors can successfully detect W-A and reject UV-B. Under reverse bias, they can detect UV-B and reject UV-A. The proof of concept design shows that it is feasible to fabricate high performance dual-band UV detectors based on the current AlGaN material growth and fabrication technologies.

  9. Detection of biological warfare agents using ultra violet-laser induced fluorescence LIDAR

    NASA Astrophysics Data System (ADS)

    Joshi, Deepti; Kumar, Deepak; Maini, Anil K.; Sharma, Ramesh C.

    This review has been written to highlight the threat of biological warfare agents, their types and detection. Bacterial biological agent Bacillus anthracis (bacteria causing the disease anthrax) which is most likely to be employed in biological warfare is being discussed in detail. Standoff detection of biological warfare agents in aerosol form using Ultra violet-Laser Induced Fluorescence (UV-LIF) spectroscopy method has been studied. Range-resolved detection and identification of biological aerosols by both nano-second and non-linear femto-second LIDAR is also discussed. Calculated received fluorescence signal for a cloud of typical biological agent Bacillus globigii (Simulants of B. anthracis) at a location of ˜5.0 km at different concentrations in presence of solar background radiation has been described. Overview of current research efforts in internationally available working UV-LIF LIDAR systems are also mentioned briefly.

  10. Gentian Violet: A 19th Century Drug Re-Emerges in the 21st Century

    PubMed Central

    Maley, Alexander M.; Arbiser, Jack L.

    2013-01-01

    Gentian violet (GV) has a long and varied history as a medicinal agent. Historically used as an anti-bacterial and anti-fungal, recent reports have shown its utility as an anti-typranosomal, anti-viral and anti-angiogenic agent. The objective of this paper is to summarize evidence regarding the efficacy, and safety of GV use in dermatology. Recent discoveries have found novel targets of GV, namely NADPH oxidase in mammalian cells and thioredoxin reductase 2 in bacterial, fungal, and parasitic cells. These discoveries have expanded the use of GV in the 21st century. Given that GV is well tolerated, effective and inexpensive, its use in dermatology is predicted to increase. PMID:24118276

  11. Dye-Sensitized Solar Cells

    NSDL National Science Digital Library

    This lesson from The Lawrence Hall of Science was taught in spring 2012 and teaches students about nano and environmental technologies. Students will create "dye-sensitized solar cells (DSSC) using nano-crystalline titanium dioxide." This page includes links to the Source Articles for the Hands-on Module and Project Staff Write-ups of the Hands-on Module. Additionally, five documents provide lecture and lab materials for instructor use.

  12. Fabrication of SnO2-Reduced Graphite Oxide Monolayer-Ordered Porous Film Gas Sensor with Tunable Sensitivity through Ultra-Violet Light Irradiation

    PubMed Central

    Xu, Shipu; Sun, Fengqiang; Yang, Shumin; Pan, Zizhao; Long, Jinfeng; Gu, Fenglong

    2015-01-01

    A new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO2-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO4 aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO2. The growing and the as-formed SnO2, just like other photocatalytic semiconductor, could be excited to produce electrons and holes under UV irradiation. Electrons reduced GO and holes adsorbed corresponding negative ions, which changed the properties of the composite film. This film was directly used as gas-sensor and was able to display high sensitivity in detecting ethanol gas. More interestingly, on the basis of SnO2-induced photochemical behaviours, this sensor demonstrated tunable sensitivity when UV irradiation time was controlled during the fabrication process and post in water, respectively. This study provides efficient ways of conducting the in situ fabrication of a semiconductor-reduced graphite oxide film device with uniform surface structure and controllable properties. PMID:25758292

  13. Dye laser traveling wave amplifier

    NASA Technical Reports Server (NTRS)

    Davidson, F.; Hohman, J.

    1985-01-01

    Injection locking was applied to a cavity-dumped coaxial flashlamp pumped dye laser in an effort to obtain nanosecond duration pulses which have both high energy and narrow-linewidth. In the absence of an injected laser pulse, the cavity-dumped dye laser was capable of generating high energy (approx. 60mJ) nanosecond duration output pulses. These pulses, however, had a fixed center wavelength and were extremely broadband (approx. 6nm FWHM). Experimental investigations were performed to determine if the spectral properties of these outputs could be improved through the use of injection-locking techniques. A parametric study to determine the specific conditions under which the laser could be injection-locked was also carried out. Significant linewidth reduction to 0.0015nm) of the outputs was obtained through injection-locking but only at wavelengths near the peak lasing wavelength of the dye. It was found, however; that by inserting weakly dispersive tuning elements in the laser cavity, these narrow-linewidth outputs could be obtained over a wide (24nm) tuning range. Since the tuning elements had low insertion losses, the tunability of the output was obtained without sacrificing output pulse energy.

  14. Predicting dye biodegradation from redox potentials.

    PubMed

    Zille, Andrea; Ramalho, Patricia; Tzanov, Tzanko; Millward, Roy; Aires, Veronika; Cardoso, Maria Helena; Ramalho, Maria Teresa; Gübitz, Georg M; Cavaco-Paulo, Artur

    2004-01-01

    Two biological approaches for decolorization of azo sulfonated dyes have been compared: reductive decolorization with the ascomycete yeast Issatchenkia occidentalis and enzymatic oxidative decolorization with Trametes villosa laccase alone or in the presence of the mediator 1-hydroxybenzotriazole. The redox potential difference between the biological cofactor involved in the reductive activity of growing cells and the azo dye is a reliable indication for the decolorization ability of the biocatalyst. A linear relationship exists between the redox potential of the azo dyes and the decolorization efficiency of enzyme, enzyme/mediator, and yeast. The less positive the anodic peak of the dye, the more easily it is degraded oxidatively with laccase. The more positive the cathodic peak of the dye, the more rapidly the dye molecule is reduced with yeast. PMID:15458349

  15. Inner-Sphere Electron-Transfer Single Iodide Mechanism for Dye Regeneration in Dye-Sensitized Solar Cells

    E-print Network

    Goddard III, William A.

    the regeneration of the oxidized dye in dye-sensitized solar cells, the redox couple of I- /I3 - reduces the photo dye- sensitized solar cell (DSSC) in 1991,1 DSSCs have been considered as promising alternativesInner-Sphere Electron-Transfer Single Iodide Mechanism for Dye Regeneration in Dye-Sensitized Solar

  16. Anthocyanin dyes in titanium dioxide nanoparticle-dye sensitized solar cells

    Microsoft Academic Search

    Hailey Cramer; Daniel Choi; Mark Griep; Shashi P. Karna

    2011-01-01

    Dye-sensitized solar cells are a class of thin-film solar cells, which can be made using low-cost materials and natural dyes. They can potentially achieve the same efficiency compared to bulky silicon photovoltaic cells, while providing many other advantages. In this research, anthocyanin dyes taken from different fruits were used in titanium dioxide dye-sensitized solar cells. The unique ability of anthocyanin

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

    Microsoft Academic Search

    Brian E. Hardin; Jun-Ho Yum; Eric T. Hoke; Young Chul Jun; Peter Pe?chy; Toma?s Torres; Mark L. Brongersma; Michael Gra?tzel; Michael D. McGehee

    2010-01-01

    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 (ETE) of 96% inside TT1-covered, mesostructured TiO2 films. Further performance increases were limited by the solubility of DCM

  18. Low-cost dyes based on methylthiophene for high-performance dye-sensitized solar cells

    Microsoft Academic Search

    Zongfang Tian; Meihua Huang; Bin Zhao; Hui Huang; Xiaoming Feng; Yujuan Nie; Ping Shen; Songting Tan

    2010-01-01

    Three donor–acceptor, ?-conjugated (D–?–A) dyes containing methylthiophene or vinylene methylthiophene as ?-conjugated spacer were utilised in dye-sensitized nanocrystalline TiO2 solar cells. The relationship between the structure of the dyes and their photophysical, electrochemical and photovoltaic properties was investigated systematically. The vinyl unit, introduced as the ?-conjugated spacer, leads to unfavorable back-electron transfer and decrease of the open-circuit voltage. A dye-sensitized

  19. Tetrahydroquinoline dyes with different spacers for organic dye-sensitized solar cells

    Microsoft Academic Search

    Ruikui Chen; Xichuan Yang; Haining Tian; Licheng Sun

    2007-01-01

    Novel organic dyes (C1-1, C1-5 and C2-1) with a tetrahydroquinoline moiety as the electron donor, different thiophene-containing electron spacers and a cyanoacrylic acid moiety as the electron acceptor have been designed and synthesized for the application in dye-sensitized solar cells (DSSCs). An interesting relationship between the dye structures, properties, and the performance of DSSCs based on these tetrahydroquinoline dyes is

  20. Heterogeneous Catalytic Ozonation of Aqueous Reactive Dye

    Microsoft Academic Search

    Kintoo Yong; Jiangning Wu; Susan Andrews

    2005-01-01

    The aqueous solution of a model reactive dye, C.I. Reactive Blue 5, was ozonated in the presence of a heterogeneous catalyst, CuS. It was found that CuS was very effective for catalyzing the decolorization so that both treatment time and ozone consumption were significantly reduced. For 1 g\\/L of the reactive dye, the stoichiometric ratios of ozone to dye in

  1. Electrochromism of an aggregating thiapyrylium dye

    Microsoft Academic Search

    A. P. Marchetti; M. Scozzafava; R. H. Young

    1988-01-01

    Electrochromism (electric-field-modulated absorption) spectra are reported for a thiapyrylium dye in a polycarbonate host. When the dye is homogeneously dissolved in the polymer, excitation to the first excited singlet state changes its dipole moment by approximately 6 D (2×10?29 C m). When the dye is aggregated with the host polymer, the structure of the aggregate is believed to consist of

  2. Chromonic liquid crystals: properties and applications as functional materials.

    PubMed

    Tam-Chang, Suk-Wah; Huang, Liming

    2008-05-01

    Chromonic liquid crystals (or chromonics) are formed by the self-organization of aromatic compounds with ionic or hydrophilic groups in aqueous solutions. This review summarizes the research on chromonic liquid crystals in the last two decades. The research embraced the studies of commercially available chromonic dyes and drugs, the syntheses and investigations of molecularly designed mesogens, the invention of novel processes for aligning chromonic liquid crystals, and the development of new applications as functional materials and biosensors. PMID:18536789

  3. Liquid crystal as laser medium with tunable gain spectra.

    PubMed

    Blinov, L M; Cipparrone, G; Lazarev, V V; Pagliusi, P; Rugiero, T

    2008-04-28

    Amplified spontaneous emission intensity and gain spectra in polarized light have been measured in a dye doped nematic liquid crystal for different orientation of its optical axis and pump intensity. A possibility for switching the gain of the liquid crystal by an external electric field is shown experimentally. The liquid crystal materials with field controlled gain can be used in microlasers and light micro-amplifiers in both planar and waveguiding geometry. PMID:18545366

  4. Spectroscopic Investigation of Ce(3+) Doped Fluoride Crystals

    NASA Technical Reports Server (NTRS)

    Reinhart, Donald H.; Armagan, Guzin; Marsh, Waverly; Barnes, James; Chai, B. H. T.

    1995-01-01

    Doping of the trivalent rare-earth cerium ion into fluoride crystals is of interest in producing turnable ultra-violet solid state lasers. These lasers are desirable for many applications in medicine, industry, and scientific research, including remote sensing. High absorption and stimulated emission cross sections of the dipole allowed 4f-5d transitions show promise in cerium as a laser ion in crystals. Several research groups have already reported the observation of stimulated emission of cerium in LiYF4, LiSrAlF6, and LiCaAlF6. However, the color center formation in the crystals due to the excited state absorption of ultra-violet pump light adds difficulty to achieving laser action. We have investigated the spectroscopic properties of cerium such as absorption and emission spectra, and lifetimes in four different fluoride crystals, including LiCaAlF6, LiSrAlF6, KyF4 and LiYF4. We have derived the polarized absorption and stimulated emission cross sections from transmission and fluorescence emission measurements for each of the host crystals. we have measured the lifetime of the lowest 5d level; moreover, investigated the temperature dependence of this lifetime and color center formation. Our results on absorption and stimulated emission cross sections for LiCaAlF6 and LiSrAlF6 are similar to the results already published.

  5. Preliminary investigation of the effects of dye concentration on the output of a multiwavelength dye laser

    NASA Technical Reports Server (NTRS)

    Clark, I. O.; Burney, L. G.

    1974-01-01

    The effects of dye concentration on the output wavelength and energy of a multiwavelength dye laser were investigated. The dyes tested were Coumarin 2 in methyl alcohol and Rhodomine 6G, Acridine Red, and 7-diethylamino-4-methyl Coumarin (7DA 4MC) in ethyl alcohol.

  6. Organic dyes incorporating low-band-gap chromophores for dye-sensitized solar cells.

    PubMed

    Velusamy, Marappan; Justin Thomas, K R; Lin, Jiann T; Hsu, Ying-Chan; Ho, Kuo-Chuan

    2005-05-12

    Versatile dyes based on benzothiadiazole and benzoselenadiazole chromophores have been developed that perform efficiently in dye-sensitized solar cells. Power conversion efficiency of 3.77% is realized for a dye in which charge recombination is probably hindered by the nonplanar charge-separated structure. PMID:15876014

  7. Industrial hygiene concerns of laser dyes

    SciTech Connect

    Miller, G.

    1990-11-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye's toxicity or mutagenicity/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity/carcinogenicity of the solvent used. Working from this information, we have proposed three control classes -- limited, moderate, and strict -- for work performed with dyes in each class. This paper describes the considerations that went into preparing our guidelines and summarizes the precautions themselves.

  8. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains for...purposes are mixtures of synthetic or natural dyes or nondye chemicals in...

  9. LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Study of relaxation times of polymethine dyes used for passive mode locking of solid-state lasers emitting between 750 and 850 nm

    NASA Astrophysics Data System (ADS)

    Grigonis, R.; Derevyanko, Nadezhda A.; Ishchenko, Aleksandr A.; Sirutkaitis, V. A.

    2001-11-01

    The relaxation times ? of the bleached states of polymethine dyes absorbing light in the 750 — 850-nm are determined by the direct pump — probe method. The effect of the dye structure and the solvent type on the relaxation time is discussed. The role of different intra- and intermolecular interactions in the relaxation of excited electronic states of the dyes is analysed. Polymethine dyes are found (with ?=11 — 75 ps) that are promising for passive mode locking in Cr3+:LiCaAlF6, Cr3+:KZnF3, and Cr3+:LiSrAlF6 crystal lasers.

  10. Estimation of Fluorescent Dye Amount in Tracer Dye Test

    NASA Astrophysics Data System (ADS)

    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 appropriate amount of tracers was found according to the flowrate of the spring. The amount of dye is very important for the consistency of the results and the applicability of the tests. For example if the amount of tracer that is estimated is found to be inadequate, any field readings and data could be lost. Most importantly tracer dye is costly and hard to prepare, transport and will follow a torturous path through the cave to the underground river.

  11. Dyeing of jute with binary mixtures of jackfruit wood and other natural dyes — Study on colour performance and dye compatibility

    Microsoft Academic Search

    Ashis Kumar Samanta; Priti Agarwal; Siddhartha Datta

    manjistha (MJ), red sandal wood (RSW), mariegold (MG), sappan wood (SW) and babool (BL), have been used to dye bleached jute fabric pre-mordanted with 20% myrobolan followed by 20% aluminium sulphate. Binary combinations of JFW with each of the five natural dye extracts have been evaluated for colour strength (K\\/S value) and its coefficient of variation, brightness index (BI), changes

  12. Theory of pulsed dye lasers including dye-molecule rotational relaxation

    SciTech Connect

    Haas, R.A.; Rotter, M.D. (Department of Applied Science, University of California, Davis-Livermore, L-794, P.O. Box 808, Livermore, California 94550 (US) Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550)

    1991-02-01

    In this paper a phenomenological semiclassical theory of pulsed-laser-pumped dye-laser light amplifiers is presented. The theory accounts for the broadband radiation absorption and emission characteristics of dye molecules in liquid solvents. Dye-molecule fluorescence, vibrational, rotational, and electric polarization relaxation processes are represented by phenomenological relaxation rates. In general, it is found that due to dye-molecule rotational relaxation the laser-pumped dye medium is optically anisotropic. The pump- and dye-laser beams propagate through the dye medium as essentially transverse electromagnetic waves whose amplitude and polarization state changes. The theory is applicable to pulse durations {tau}{approx lt}10--100 ns including the ultrashort pulse regime. The regime {tau}{approx gt}1 ps in which the pump- and dye-laser pulse lengths are long compared to the dye-molecule vibrational and electric polarization relaxation times is considered in detail. Amplification of partially polarized quasimonochromatic light is described by a self-consistent set of equations for the components of the pump- and dye-laser light coherency matrices and the orientation populations of the lowest vibronic levels of the dye molecule's {ital S}{sub 0} and {ital S}{sub 1} electronic states.

  13. High efficiency dye laser with low fluorescence yield pyrromethene dyes: experimental and theoretical studies

    NASA Astrophysics Data System (ADS)

    Jagtap, K. K.; Maity, D. K.; Ray, A. K.; Dasgupta, K.; Ghosh, S. K.

    2011-06-01

    A combined experimental and theoretical study of the photo-physical, laser properties and molecular structures of three relatively recent Pyrromethene (PM) class dyes, PM597, PM580 and PM567, have been carried out. Laser characteristics of these three PM dyes were compared with three other widely used Rhodamine (RH) class dyes, RH6G, RHB and KRS, using a narrow-band dye laser setup, transversely pumped by the second harmonic (532 nm) of a Q-switched Nd-YAG laser. In addition to generating comparative data of these dyes for optimal use in dye lasers, we observed that unlike the RH dyes, the PM dyes show high efficiencies and wide tunability, despite the low fluorescence yield and high rate of non-radiative decay. Particularly, PM597 dye, in spite of a very low quantum yield of fluorescence (?=0.42), high non-radiative decay rate, and a large distortion from planarity in its excited state, when used in a laser cavity it exhibited similar laser efficiency and a beneficially wider tuning curve in comparison to other two PM dyes. Theoretical studies were carried out applying density functional theory and time-dependent density functional theory (DFT/TDDFT) to obtain new information on ground and the first excited state geometrical parameters of the PM dyes. Good correlation between calculated molecular properties and experimental results was observed for the evolution of the longest wavelength absorption maximum.

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

    NASA Astrophysics Data System (ADS)

    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.

  15. On the correlation between dye coverage and photoelectrochemical performance in dye-sensitized solar cells.

    PubMed

    Johansson, Viktor; Ellis-Gibbings, Lilian; Clarke, Trevor; Gorlov, Mikhail; Andersson, Gunther G; Kloo, Lars

    2014-01-14

    Concentration depth profiles of the ruthenium based dyes Z907 and N719 adsorbed onto titania are measured directly and used for determining the adsorption isotherm of the dyes. Dye layers formed by both grow in islands on the titania which do not cover the entire titania surface even at the maximum coverage. Impedance spectroscopy in conjunction with the adsorption isotherms shows that recombination losses mainly appear between the dye and the electrolyte solution. The short circuit current and the efficiency increase linearly with the dye coverage. The open circuit voltage slightly increases with increasing dye coverage which is interpreted as most likely to be a consequence of the higher charge in the particles upon higher dye loading on the TiO2 surface. PMID:24263223

  16. Dyeing behaviour of gamma irradiated cotton fabric using Lawson dye extracted from henna leaves (Lawsonia inermis)

    NASA Astrophysics Data System (ADS)

    Rehman, Fazal-ur; Adeel, Shahid; Qaiser, Summia; Ahmad Bhatti, Ijaz; Shahid, Muhammad; Zuber, Mohammad

    2012-11-01

    Dyeing behavior of gamma irradiated cotton fabric using Lawson dye extracted from henna leaves has been investigated. Cotton and dye powder are irradiated to different absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. The dyeing parameters such as dyeing time, electrolyte (salt) concentration and mordant concentrations using copper and iron as mordants are optimized. Dyeing is performed using un-irradiated and irradiated cotton with dye solutions and their color strength values are evaluated in CIE Lab system using Spectraflash -SF650. Methods suggested by International Standard Organization (ISO) have been employed to investigate the colourfastness properties such as colourfastness to light, washing and rubbing of irradiated dyed fabric. It is found that gamma ray treatment of cotton dyed with extracts of henna leaves has significantly improved the color strength as well as enhanced the rating of fastness properties.

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

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

  18. Reduction of azo dyes by desulfovibrio desulfuricans

    Microsoft Academic Search

    E. S. Yoo; J. Libra; U. Wiesmann

    2000-01-01

    Azo dyes are widely used in textile finishing, and have become of concern in wastewater treatment because of their color, bio-recalcitrance, and potential toxicity to animals and humans. Thus, wastewater with azo dyes must be decolorized and furthermore mineralized in appropriate systems combining biological and chemical processes. In this study, the potential for sulfate reducing bacteria (SRB) to decolorize azo

  19. Use of slag for dye removal

    SciTech Connect

    Ramakrishna, K.R.; Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

    1998-09-01

    Adsorption techniques employing activated carbon have been found to be reasonably effective in the removal of some of the ionic impurities in water. However, economic considerations may require the use of inexpensive sorbents which are either naturally available or available as waste products from manufacturing processes. Slag is one such waste product obtained during the manufacture of steel, and the present study investigates dye removal characteristics of slag from colored waters. Aqueous solutions prepared from commercial grade acid, basic, and disperse dyes were used in this study, and batch pH, kinetic, and isotherm studies were undertaken on a laboratory scale. The data were evaluated for applicability to the Langmuir, Freundlich, and BET isotherm models, and the removal capacity of slag was compared with that of granular activated carbon. Results indicated approximately 94% removal of the disperse dye by slag, compared with a removal of approximately 49% achieved by activated carbon. Removal of acid dyes (dyes containing anionic groups) was reasonably good (approximately 47 and 74%), though not as good as obtained using activated carbon (approximately 100%). Column studies were conducted with a disperse dye (nonionic, slightly soluble in water), and analysis of data showed a sorption capacity of 1.3 mg of disperse dye per gram of slag. However, effluent dye concentrations were found to be higher than the permissible levels for discharge to receiving waters.

  20. ORGANIC DYES AND PIGMENTS DATA BASE

    EPA Science Inventory

    The objective of this research program was to compile a data base covering all the commercially significant dyes and pigments produced or imported in the United States. The Organic Dyes and Pigments Data Base (ODPDB) contains the following data elements: chemical-related data (co...

  1. Removal of cationic dyes by kaolinite

    Microsoft Academic Search

    M. Hamdi Karao?lu; Mehmet Do?an; Mahir Alkan

    2009-01-01

    The removal of cationic dyes such as maxilon yellow 4GL (MY 4GL) and maxilon red GRL (MR GRL) on kaolinite from aqueous solutions has been studied according to the adsorption method. The adsorbed amount of dyes on kaolinite surface was investigated as a function of pH, ionic strength, temperature, acid activation, and calcination temperature. It was found that: (i) the

  2. Quirks of dye nomenclature. 2. Congo red.

    PubMed

    Cooksey, C J

    2014-07-01

    The history, origin, identity, chemistry and uses of Congo red are described. Originally patented in 1884, Congo red soon found applications in dyeing cotton, as a pH indicator for chemists and as a biological stain. Unlike the majority of the 19th century synthetic dyes, it still is available commercially. PMID:24520883

  3. Fungal decolorization of dye wastewaters: a review

    Microsoft Academic Search

    Yuzhu Fu; T Viraraghavan

    2001-01-01

    In recent years, there has been an intensive research on fungal decolorization of dye wastewater. It is becoming a promising alternative to replace or supplement present treatment processes. This paper examines various fungi, living or dead cells, which are capable of decolorizing dye wastewaters; discusses various mechanisms involved; reports some elution and regeneration methods for fungal biomass; summarizes the present

  4. Response of Hydrilla to selected dyes

    Microsoft Academic Search

    John Barltrop; Barbara B. Martin; Dean F. Martin

    1982-01-01

    The perennial submersed noxious aquatic plant Hydrilla verticillata (Royle) was treated with well water solutions of methylene blue, hematoporphyrin, and Eosin Y, and compared with control systems. Statistically significant reductions in growth were observed for treatments with all three dyes at initial dye concentrations of 10 M. Typically, reductions in growth of 30 percent on a relative basis for the

  5. Snow Crystals

    NSDL National Science Digital Library

    Kenneth Libbrecht

    1999-02-01

    This site is all about snow crystals and snowflakes. The many facets of snow crystals are described here, along with attempts to understand their formation. This site includes collections of super-high-resolution snow crystal photos, as well as links to learn about snow crystal classifications and how to make snow crystal fossils. Included in the study of how snow crystals form, these researchers have created snow crystals in the laboratory. Their snow crystal galleries include selections of images and movies of laboratory-grown snow crystals, as well as information on how to make your own snow crystals. The snow crystal primer describes what snow crystals are, how they form, and why they form the way they do. There is also a section on snow crystal physics.

  6. Covalent anthocyanin-flavonol complexes from the violet-blue flowers of Allium 'Blue Perfume'.

    PubMed

    Saito, Norio; Nakamura, Maiko; Shinoda, Koichi; Murata, Naho; Kanazawa, Toshinari; Kato, Kazuhisa; Toki, Kenjiro; Kasai, Hiroko; Honda, Toshio; Tatsuzawa, Fumi

    2012-08-01

    Three covalent anthocyanin-flavonol complexes (pigments 1-3) were extracted from the violet-blue flower of Allium 'Blue Perfume' with 5% acetic acid-MeOH solution, in which pigment 1 was the dominant pigment. These three pigments are based on delphinidin 3-glucoside as their deacylanthocyanin and were acylated with malonyl kaempferol 3-sophoroside-7-glucosiduronic acid or malonyl-kaempferol 3-p-coumaroyl-tetraglycoside-7-glucosiduronic acid in addition to acylation with acetic acid. By spectroscopic and chemical methods, the structures of these three pigments 1-3 were determined to be: pigment 1, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-?-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-(3(III)-O-(?-glucopyranosyl(V))-?-glucopyranosyl(III))-4(II)-O-(trans-p-coumaroyl)-6(II)-O-(?-glucopyranosyl(IV))-?-glucopyranoside(II))-7-O-(?-glucosiduronic acid(VI)))) malonate; pigment 2, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-?-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-?-glucopyranosyl(III))-?-glucopyranoside(II))-7-O-(?-glucosiduronic acid(VI)))); and pigment 3, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-?-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-(3(III)-O-(?-glucopyranosyl(V))-?-glucopyranosyl(III))-4(II)-O-(cis-p-coumaroyl)-6(II)-O-(?-glucopyranosyl(IV))-?-glucopyranoside(II))-7-O-(?-glucosiduronic acid(VI)))) malonate. The structure of pigment 2 was analogous to that of a covalent anthocyanin-flavonol complex isolated from Allium schoenoprasum where delphinidin was observed in place of cyanidin. The three covalent anthocyanin-flavonol complexes (pigment 1-3) had a stable violet-blue color with three characteristic absorption maxima at 540, 547 and 618nm in pH 5-6 buffer solution. From circular dichroism measurement of pigment 1 in the pH 6.0 buffer solution, cotton effects were observed at 533 (+), 604 (-) and 638 (-) nm. Based on these results, these covalent anthocyanin-flavonol complexes were presumed to maintain a stable intramolecular association between delphinidin and kaempferol units closely related to that observed between anthocyanin and hydroxycinnamic acid residues in polyacylated anthocyanins. Additionally, an acylated kaempferol glycoside (pigment 4) was isolated from the same flower extract, and its structure was determined to be kaempferol 3-O-sophoroside-7-O-(3-O-(malonyl)-?-glucopyranosiduronic acid). PMID:22704652

  7. Multicolor fluorescence enhancement from a photonics crystal surface

    PubMed Central

    Pokhriyal, A.; Lu, M.; Huang, C. S.; Schulz, S.; Cunningham, B. T.

    2010-01-01

    A photonic crystal substrate exhibiting resonant enhancement of multiple fluorophores has been demonstrated. The device, fabricated uniformly from plastic materials over a ?3×5 in.2 surface area by nanoreplica molding, utilizes two distinct resonant modes to enhance electric field stimulation of a dye excited by a ?=632.8 nm laser (cyanine-5) and a dye excited by a ?=532 nm laser (cyanine-3). Resonant coupling of the laser excitation to the photonic crystal surface is obtained for each wavelength at a distinct incident angle. Compared to detection of a dye-labeled protein on an ordinary glass surface, the photonic crystal surface exhibited a 32× increase in fluorescent signal intensity for cyanine-5 conjugated streptavidin labeling, while a 25× increase was obtained for cyanine-3 conjugated streptavidin labeling. The photonic crystal is capable of amplifying the output of any fluorescent dye with an excitation wavelength in the 532 nmdyes within a single imaged area, such as gene expression microarrays. PMID:20957067

  8. Nonlinear dye response under nitrogen laser pumping

    NASA Astrophysics Data System (ADS)

    Milani, Marziale; Ferraro, Lorenzo

    2002-03-01

    Nitrogen lasers have been used since many years to make dye solutions to lase. A nitrogen laser (337.1 nm) TEA at atmospheric pressure has been built in our laboratory. It has been characterized and used to pump cells of different sizes containing different dyes: Rhodamine 6G, Coumarin 440, DOTCI and pyranine. As a preliminary result it has been shown that pyranine can lase, and this happens at very low threshold. Moreover, we have found that, independently on the dye concentration in the solvent, the dyes under consideration can be grouped into two major classes of behavior: Rhodamine 6G and DOTCI can lase both axially and transversally; Coumarin 440 and pyranine can lase only axially. Other intriguing features will be discussed and attention will be devoted to simultaneous multiple beam generation, superfluorescence and distributed axial pumping of dye solutions.

  9. Blue-violet photoluminescence from amorphous Si-in-SiNx thin films with external quantum efficiency in percentages

    Microsoft Academic Search

    L. B. Ma; R. Song; Y. M. Miao; C. R. Li; Y. Q. Wang; Z. X. Cao

    2006-01-01

    Bright blue-violet photoluminescence centered at 428 nm was obtained in amorphous Si-in-SiNx thin films prepared in a cyclic growth mode on cool substrates by plasma-enhanced chemical vapor deposition, in which the typical size of the silicon particles has been brought down to ?1.80 nm and the number density amounts to 1.07×1013 cm2. A maximum external quantum efficiency over 3.0% was

  10. Blue-violet photoluminescence from amorphous Si-in-SiNx thin films with external quantum efficiency in percentages

    Microsoft Academic Search

    L. B. Ma; R. Song; Y. M. Miao; C. R. Li; Y. Q. Wang; Z. X. Cao

    2006-01-01

    Bright blue-violet photoluminescence centered at 428 nm was obtained in amorphous Si-in-SiNx thin films prepared in a cyclic growth mode on cool substrates by plasma-enhanced chemical vapor deposition, in which the typical size of the silicon particles has been brought down to ~1.80 nm and the number density amounts to 1.07×1013 cm2. A maximum external quantum efficiency over 3.0% was

  11. Vertical cavity violet light emitting diode incorporating an aluminum gallium nitride distributed Bragg mirror and a tunnel junction

    Microsoft Academic Search

    M. Diagne; Y. He; H. Zhou; E. Makarona; A. V. Nurmikko; J. Han; K. E. Waldrip; J. J. Figiel; T. Takeuchi; M. Krames

    2001-01-01

    We have designed and implemented a vertical cavity violet light emitting diode which features an optical resonator composed of an in situ grown GaN\\/AlGaN DBR and a high reflectivity dielectric mirror. The active InGaN MQW medium is grown directly atop the AlGaN DBR and the structure includes an intracavity lateral current spreading layer based on a p++\\/n++ InGaN\\/GaN tunnel junction.

  12. Microwave-assisted synthesis of platinum nanoparticles and their catalytic degradation of methyl violet in aqueous solution

    NASA Astrophysics Data System (ADS)

    Pal, Jolly; Deb, Manas Kanti; Deshmukh, Dhananjay Kumar; Sen, Bhupendra Kumar

    2014-01-01

    A green synthesis of polyvinylpyrrolidone stabilized platinum nanoparticles (PtNPs) has been done by microwave irradiation in the presence of glucose. The formation process of the PtNPs is pursued by UV-visible spectroscopy. The morphology of the PtNPs was characterized by transmission electron microscopy and X-ray diffraction techniques. Catalytic activity of the above PtNPs has been substantiated through photodecolorization of aqueous methyl violet solution.

  13. Crystal Creations.

    ERIC Educational Resources Information Center

    Whipple, Nona; Whitmore, Sherry

    1989-01-01

    Presents a many-faceted learning approach to the study of crystals. Provides instructions for performing activities including crystal growth and patterns, creating miniature simulations of crystal-containing rock formations, charcoal and sponge gardens, and snowflakes. (RT)

  14. Planar super-oscillatory lens for sub-diffraction optical needles at violet wavelengths

    NASA Astrophysics Data System (ADS)

    Yuan, Guanghui; Rogers, Edward T. F.; Roy, Tapashree; Adamo, Giorgio; Shen, Zexiang; Zheludev, Nikolay I.

    2014-09-01

    Planar optical lenses are fundamental elements of miniaturized photonic devices. However, conventional planar optical lenses are constrained by the diffraction limit in the optical far-field due to the band-limited wavevectors supported by free-space and loss of high-spatial-frequency evanescent components. As inspired by Einstein's radiation `needle stick', electromagnetic energy can be delivered into an arbitrarily small solid angle. Such sub-diffraction optical needles have been numerically investigated using diffractive optical elements (DOEs) together with specially polarized optical beams, but experimental demonstration is extremely difficult due to the bulky size of DOEs and the required alignment precision. Planar super-oscillatory lenses (SOLs) were proposed to overcome these constraints and demonstrated that sub-diffraction focal spots can actually be formed without any evanescent waves, making far-field, label-free super-resolution imaging possible. Here we extend the super-oscillation concept into the vectorial-field regime to work with circularly polarized light, and experimentally demonstrate, for the first time, a circularly polarized optical needle with sub-diffraction transverse spot size (0.45?) and axial long depth of focus (DOF) of 15? using a planar SOL at a violet wavelength of 405 nm. This sub-diffraction circularly polarized optical needle has potential applications in circular dichroism spectroscopy, super-resolution imaging, high-density optical storage, heat-assisted magnetic recording, nano-manufacturing and nano-metrology.

  15. Theoretical study of the dissociation energy and the red and violet band systems of CN

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1987-01-01

    The dissociation energy (D sub O) of CN is determined to be 7.65 + or - 0.06 eV. This corresponds to delta H sub f (CN) = 105.3 + or - 1.5 kcal/mole, in excellent agreement with Engleman and Rouse (1975), but considerably larger than the recent value deduced from shock-tube studies by Colket (1984). The result is obtained not only from extensive ab initio MRCI calculations using a very large Gaussian basis set, but also from extrapolation of the directly computed value by comparison of computed and experimental results fo NO, C2, and N2. As an additional calibration of the methods, the D sub O value for CN was computed from the corresponding value for CN(-) using the experimental electron affinity data. The lifetime of the nu prime = 0 level of the violet (B 2 sigma + yields X 2 sigma +) system was computed to be 62.4 ns, in good agreement with both experiment and previous calculations. Lifetimes for the red (A 2 pi yields X 2 sigma +) system decrease with increasing nu prime, which is consistent both with the recent experiment and calculations. While the computed lifetimes are significantly longer that those obtained from the experiment, they are shorter than those deduced from an analysis of the solar spectrum. However the D sub O and f (sub OO) are consistent with Lambert's model for the solar spectrum.

  16. A model for multilayer analysis in a coated extreme ultra-violet lithography projection system

    NASA Astrophysics Data System (ADS)

    Wang, Jun; Jin, Chun-shui; Wang, Li-ping; Xie, Yao

    2014-12-01

    Reflection-enhancing multilayer coating is one of the key technologies in Extreme Ultra-Violet Lithography (EUVL). The typical thickness of the Mo/Si multilayer coatings generally adopted in EUVL is about 300 nm, which is much greater than the operating wavelength of 13.5 nm. The EUV is reflected completely back to the vacuum before punching the substrate. This changes the actual reflective surface by dozens of waves and creates extra aberrations. In this study, an equivalent working surface model for multilayer analysis based on the energy conservation principle was developed. Under the premise of the same energy modulation function for real and model film systems, each multilayer film coated optical element with complex energy propagation is transformed into a single surface. Optical design software can be used to assess these virtual surface in terms of estimation and optimization. Finally, the model was applied to a same Schwarzschild system but with different coating solutions. And the best solution was confirmed in which the coating-induced aberrations could be compensated for by image defocus.

  17. Violet Polymer Light Emitting Devices (pled's) Based on Pyrrolopyridazine Triester - N-Vinyl Carbazole) (pvk).

    NASA Astrophysics Data System (ADS)

    Lee, Moon Ky; Kim, Chang-Hwan; Naik, Akshay; Shinar, Joseph; Cheng, Yang; Wudl, Fred

    2002-03-01

    Violet spun-coated PLED's based on PPZ-doped PVK (PPZ:PVK) are described. The photoluminescence (PL) of the PPZ-oil derivative and the electroluminescence (EL) of the devices, with either an indium tin oxide (ITO) anode or an ITO/poly(3,4-ethylene dioxy-2,4-thiophene)-polystyrene sulfonate (PEDOT-PSS) anode, peak at 428 nm. Although absolute PL quantum yield ?_PL measurements on the PPZ-oil yielded ?_PL ? 40fabricate devices by vacuum sublimation of PPZ failed. However, the ITO/PEDOT-PSS/PPZ:PVK/Ca devices yielded a luminance of 34 Cd/m^2 at a bias of 16 V, which corresponds to 3000 Cd/m^2 at 555 nm. In comparison, the luminance of similar devices without the PEDOT-PSS layer was weaker by a factor of 6. As the unencapsulated devices degraded, the 430 nm emission band weakened and a red band, peaking at 610 nm, grew. However, the growth of this red emission band was also observed in undoped ITO/PEDOT-PSS/PVK/Ca devices, and it is therefore not attributable to the PPZ dopant. ^*Ames Laboratory is operated by Iowa State University for the USDOE under Contract W-7405-Eng-82.

  18. Dispersive kinetics of nonphotochemical hole burning and spontaneous hole filling: Cresyl Violet in polyvinyl films

    SciTech Connect

    Shu, L.; Small, G.J. (Department of Chemistry and Ames Laboratory U.S. Department of Energy, Iowa State University, Ames, Iowa 50011 (United States))

    1992-05-01

    The dispersive kinetics of nonphotochemical burning and spontaneous filling of the zero-phonon hole of Cresyl Violet in polyvinyl alcohol at 1.6 K are analyzed in terms of the standard external two-level system (TLS{sub {ital ezt}}) model for probe--glass systems and a distribution function for the tunnel frequency derived from a normal distribution function for the tunnel parameter {lambda}. Average values for the relaxation rates for burning and filling are determined. It is shown that the dominant mechanism for filling is not global spectral diffusion but rather antihole reversion. A high degree of positive correlation between the rates of burning and filling associated with the TLS{sub {ital ext}} is found. A new methodology that permits a more physically reasonable interpretation of spontaneous hole-filling kinetics is described. It is based on the hypothesis that only a fraction of burned sites, on reversion to the ground state, yield sites with resonance frequencies that lie within the hole profile.

  19. Simultaneous determination of malachite green, gentian violet and their leuco metabolites in catfish or trout tissue by high-performance liquid chromatography with visible detection

    Microsoft Academic Search

    Larry G. Rushing; Harold C. Thompson

    1997-01-01

    A sensitive analytical procedure for the determination of residues of leucomalachite green (LMG)-malachite green (MG) and leucogentian violet (LGV)-gentian violet (GV) in catfish or trout tissue is presented. Frozen (?20°C) fish fillets were cut into small pieces and blended in a Waring blender. A 20-g amount of homogenized fish tissue was extracted with acetonitrile-buffer, partitioned against methylene chloride, and cleaned

  20. ZnO Nanotube Based Dye-Sensitized Solar Cells

    E-print Network

    ZnO Nanotube Based Dye-Sensitized Solar Cells Alex B. F. Martinson,, Jeffrey W. Elam, Joseph T templated by anodic aluminum oxide for use in dye-sensitized solar cells (DSSCs). Atomic layer deposition of the best dye- sensitized solar cells (DSSCs) is the product of a dye with moderate extinction

  1. An expert system for the dyeing recipes determination

    Microsoft Academic Search

    R. Convert; L. Schacher; P. Viallier

    2000-01-01

    This article deals with the modelization of the reasoning of an expert in dyeing. The dyeing operation is one of the latest stage in the whole textile process which alters the intrinsic properties of the articles. At present, there are expert systems for dyeing industries. Most of them have been developed by dyes and chemical auxiliary suppliers, and these tools

  2. Ecofriendly ultrasonic natural dyeing of cotton fabric with enzyme pretreatments

    Microsoft Academic Search

    Padma S. Vankar; Rakhi Shanker

    2008-01-01

    Ecofriendly ultrasonic textile dyeing with natural dyes such as Acacia catechu and Tectona grandis show better and faster dye uptake after enzyme pretreatment on cotton fabric, and results of dyeing are better than metal mordanted fabric. It is observed that there is marked improvement in wash-fastness and light-fastness. The role of enzyme pretreatment is primarily for better absorbency, adherence and

  3. Removal of Congo Red dye by adsorption onto phyrophyllite

    Microsoft Academic Search

    Muhammad Bachri Amran; Muhammad Ali Zulfikar

    2010-01-01

    Synthetic dye?containing wastewaters from textile, paper, plastic and leather?tanning industries are a most common organic pollutant. Such dyes may be toxic not only to aquatic life, but also to human beings. Consequently, dye removal from wastewater significantly benefits the environment. The aim of this study was to investigate the effectiveness of phyrophyllite as an adsorbent for Congo Red dye from

  4. Ultrasound for wool dyeing and finishing.

    PubMed

    McNeil, S J; McCall, R A

    2011-01-01

    The effects of ultrasound at 35-39 kHz on several wool dyeing and finishing processes have been investigated as a way of reducing environmental impact. Ultrasound improved the effectiveness of cleaning scoured wool in water and to a lesser extent in water-nonionic surfactant. Scanning electron microscopy did not indicate any surface damage. Fluorescence microscopy revealed increased levels of sulphydryl groups on the wool surface suggesting ultrasound caused the removal of thioester-bound lipids. Ultrasound pre-treatment increased the effectiveness of subsequent oxidative-reductive bleaching, but had no effect on the uptake of acid levelling and acid milling dyes. The pre-treatment retarded the uptake of reactive dye, possibly by increasing the crystallinity of the fibre or removing surface bound lipids. Ultrasound did not improve dyeing under conditions that are currently used in industry, but did show potential to reduce the chemical and energy requirements of dyeing wool with reactive and acid milling dyes, but not acid levelling dyes. PMID:20675174

  5. Electronic structure of Fe- vs. Ru-based dye molecules

    SciTech Connect

    Johnson, Phillip S.; Himpsel, F. J. [Department of Physics, University of Wisconsin-Madison, 1150 University Ave., Madison, Wisconsin 53706 (United States); Cook, Peter L. [Natural Sciences Department, University of Wisconsin-Superior, Belknap and Catlin, Superior, Wisconsin 54880 (United States); Zegkinoglou, Ioannis [Department of Physics, University of Wisconsin-Madison, 1150 University Ave., Madison, Wisconsin 53706 (United States); Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Garcia-Lastra, J. M. [Dpto. Fisica de Materiales, Nano-Bio Spectroscopy Group and ETSF Scientific Development Centre, Centro de Fisica de Materiales CSIC-UPV-MPC and DIPC, Universidad del Pais Vasco, Av. Tolosa 72, E-20018 San Sebastian (Spain); Department of Physics, Center for Atomic-scale Materials Design, DTU, DK-2800 Kongens Lyngby (Denmark); Rubio, Angel [Dpto. Fisica de Materiales, Nano-Bio Spectroscopy Group and ETSF Scientific Development Centre, Centro de Fisica de Materiales CSIC-UPV-MPC and DIPC, Universidad del Pais Vasco, Av. Tolosa 72, E-20018 San Sebastian (Spain); Ruther, Rose E. [NSF Center for Sustainable Materials Chemistry, Oregon State University, Corvallis, Oregon 97331-4003, USA and University of Oregon, Eugene, Oregon 97403-1253 (United States); Hamers, Robert J. [Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave., Madison, Wisconsin 53706 (United States)

    2013-01-28

    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, octahedral N cage, such as tris(bipyridines) and tris(phenanthrolines), exhibit a systematic downward shift of the N 1s-to-{pi}* transition when Ru is replaced by Fe. This shift is explained by an extra transfer of negative charge from the metal to the N ligands in the case of Fe, which reduces the binding energy of the N 1s core level. The C 1s-to-{pi}* transitions show the opposite trend, with an increase in the transition energy when replacing Ru by Fe. Molecules with the metal in a fourfold, planar N cage (porphyrins) exhibit a more complex behavior due to a subtle competition between the crystal field, axial ligands, and the 2+ vs. 3+ oxidation states.

  6. Electronic structure of Fe- vs. Ru-based dye molecules.

    PubMed

    Johnson, Phillip S; Cook, Peter L; Zegkinoglou, Ioannis; García-Lastra, J M; Rubio, Angel; Ruther, Rose E; Hamers, Robert J; Himpsel, F J

    2013-01-28

    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, octahedral N cage, such as tris(bipyridines) and tris(phenanthrolines), exhibit a systematic downward shift of the N 1s-to-?* transition when Ru is replaced by Fe. This shift is explained by an extra transfer of negative charge from the metal to the N ligands in the case of Fe, which reduces the binding energy of the N 1s core level. The C 1s-to-?* transitions show the opposite trend, with an increase in the transition energy when replacing Ru by Fe. Molecules with the metal in a fourfold, planar N cage (porphyrins) exhibit a more complex behavior due to a subtle competition between the crystal field, axial ligands, and the 2+ vs. 3+ oxidation states. PMID:23387617

  7. Novel aminobenzanthrone dyes for amyloid fibril detection

    NASA Astrophysics Data System (ADS)

    Vus, Kateryna; Trusova, Valeriya; Gorbenko, Galyna; Kirilova, Elena; Kirilov, Georgiy; Kalnina, Inta; Kinnunen, Paavo

    2012-04-01

    A series of novel fluorescent aminobenzanthrone dyes have been tested for their ability to identify and characterize the oligomeric and fibrillar aggregates of lysozyme. The parameters of the dye binding to native, oligomeric and fibrillar protein have been calculated from the results of fluorimetric titration. Furthermore, several additional quantities reflecting the preference of the probe to either pre-fibrillar or fibrillar protein aggregates, have been evaluated. Based on the comparative analysis of the recovered parameters, AM4 was recommended for selective detection of protein pre-fibrillar assemblies, while the dyes AM1, AM2, AM3 were selected as the most prospective amyloid tracers.

  8. Decolourisation of Red 5 MB dye by microbes isolated from textile dye effluent.

    PubMed

    Subashini, P; Hiranmaiyadav, R; Premalatha, M S

    2010-07-01

    One of the major environmental problems is the presence of dye materials in textile wastewater, which need to be removed before releasing into the environment. Some dyes are toxic and carcinogenic in nature. The discharge of the textile effluent into rivers and lakes leads to higher BOD causing threat to aquatic life. Development of efficient dye degradation requires suitable strain and its use under favorable condition to realize the degradation potential. In this study, three microorganisms were isolated from the Red 5 MB dye containing textile wastewater. They were identified and tested for the dye decolourisation provided with different sugars as carbon source. The percentage of dye decolorized by Bacillus subtilis, Aspergillus flavus and Aspergillus fumigatus were found to be about 40%, 75% and 53.8% respectively. PMID:21391393

  9. Crystal fields of porphyrins and phthalocyanines

    NASA Astrophysics Data System (ADS)

    Johnson, P. S.; Boukahil, I.; Himpsel, F. J.; Kennedy, C.; Jersett, N.; Cook, P. L.; Garcia-Lastra, J. M.

    2014-03-01

    Polarization-dependent X-ray absorption spectroscopy at the N 1s and metal 2p edges is combined with density functional and atomic multiplet calculations to determine the crystal field parameters 10Dq, Ds, and Dt of transition metal (Mn, Fe, Co, Ni) phthalocyanines and octaethylporphyrins. Octaethyl porphyrins are observed to lie flat on Si with native oxide, while phthalocyanines lie on edge. Strong polarization dependence is found at all edges, which facilitates a unique determination of the crystal field parameters. Crystal field values from PBE density functional calculations provide helpful starting values, which are refined by fitting atomic multiplet calculations to the data. Since the crystal field affects electron-hole separation in solar cells, the systematic set of crystal field parameters obtained here can be useful for optimizing dyes for solar cells.

  10. Optimization of alkaline extraction of natural dye from Henna leaves and its dyeing on cotton by exhaust method

    Microsoft Academic Search

    Shaukat Ali; Tanveer Hussain; Rakhshanda Nawaz

    2009-01-01

    The alkaline conditions for extraction of natural dye from Henna leaves were optimized and the resulting extract was used to further optimize its dyeing conditions on cotton by exhaust method. Dyeings without any mordant were compared with those obtained with premordanting and postmordanting with alum and iron. It was found that dyeings produced with alkaline extracts of Henna leaves have

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

    Microsoft Academic Search

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

    2010-01-01

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

  12. Designing dye-nanochannel antenna hybrid materials for light harvesting, transport and trapping.

    PubMed

    Calzaferri, Gion; Méallet-Renault, Rachel; Brühwiler, Dominik; Pansu, Robert; Dolamic, Igor; Dienel, Thomas; Adler, Pauline; Li, Huanrong; Kunzmann, Andreas

    2011-02-25

    We discuss artificial photonic antenna systems that are built by incorporating chromophores into one-dimensional nanochannel materials and by organizing the latter in specific ways. Zeolite L (ZL) is an excellent host for the supramolecular organization of different kinds of molecules and complexes. The range of possibilities for filling its one-dimensional channels with suitable guests has been shown to be much larger than one might expect. Geometrical constraints imposed by the host structure lead to supramolecular organization of the guests in the channels. The arrangement of dyes inside the ZL channels is what we call the first stage of organization. It allows light harvesting within the volume of a dye-loaded ZL crystal and also the radiationless transport of energy to either the channel ends or center. One-dimensional FRET transport can be realized in these guest-host materials. The second stage of organization is realized by coupling either an external acceptor or donor stopcock fluorophore at the ends of the ZL channels, which can then trap or inject electronic excitation energy. The third stage of organization is obtained by interfacing the material to an external device via a stopcock intermediate. A possibility to achieve higher levels of organization is by controlled assembly of the host into ordered structures and preparation of monodirectional materials. The usually strong light scattering of ZL can be suppressed by refractive-index matching and avoidance of microphase separation in hybrid polymer/dye-ZL materials. The concepts are illustrated and discussed in detail on a bidirectional dye antenna system. Experimental results of two materials with a donor-to-acceptor ratio of 33:1 and 52:1, respectively, and a three-dye system illustrate the validity and challenges of this approach for synthesizing dye-nanochannel hybrid materials for light harvesting, transport, and trapping. PMID:21337487

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

    Microsoft Academic Search

    N. M. Gómez-Ortíz; I. A. Vázquez-Maldonado; A. R. Pérez-Espadas; G. J. Mena-Rejón; J. A. Azamar-Barrios; G. Oskam

    2010-01-01

    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 1H-NMR, FTIR spectroscopy, and UV–Vis spectrophotometry. Solar cells were prepared using TiO2

  14. The improved performance of dye sensitized solar cells by bifunctional aminosilane modified dye sensitized photoanode

    Microsoft Academic Search

    Jing Zhang; Guangtao Yang; Qiang Sun; Jun Zheng; Peiqing Wang; Yuejin Zhu; Xingzhong Zhao

    2010-01-01

    The dye sensitized photoanode is modified by the bifunctional 3-aminopropyltriethoxysilane (APTS). The attenuated total reflection–Fourier transform infrared spectroscopy, the UV-IR spectroscopy, the dye adsorption amount, and the electrochemical impedance spectroscopy were carried out to examine the modification effect. The experiments indicated that the APTS with amino endgroup and triethoxysilane group deprotonated the surface of the dye sensitized photoanode and formed

  15. A new class of organic dyes based on acenaphthopyrazine for dye-sensitized solar cells

    Microsoft Academic Search

    Zhixia Kong; Huizhi Zhou; Jingnan Cui; Tingli Ma; Xichuan Yang; Licheng Sun

    2010-01-01

    A new class of organic dyes based on acenaphthopyrazine derivatives, containing pyrazine group as the electron acceptor and o-dicarboxyl acids as the anchoring groups were designed and synthesized for application in dye-sensitized solar cells (DSCs). These dyes have short synthesis routes and are easily adsorbed on the surface of TiO2. Under illumination of simulated AM1.5 solar light (100mWcm?2), a total

  16. Synthesis and application of novel crosslinking polyamine dyes with good dyeing performance

    Microsoft Academic Search

    Yingling Li; Shufen Zhang; Jinzong Yang; Song Jiang; Qian Li

    2008-01-01

    Novel crosslinking dyes were synthesized using tetraethylenepentamine. A series of novel red polyamine crosslinking dyes D1–D7 based on benzoyl H-acid sulfonamide were prepared via the reaction of it with diazo salts of aniline, p-toluidine, o-methoxyaniline, p-aminophenol, p-nitraniline, m-aminobenzene sulfonic acid, 1-aminonaphthalene-5-sulfonic acid, respectively. Two novel polyamine crosslinking dyes were synthesized via the reactions of tetraethylenepentamine with C.I. Reactive Red 2

  17. Studies on Dyeing Performance of Novel Acid Azo Dyes and Mordent Acid Azo Dyes Based on 2,4-Dihydroxybenzophenone

    Microsoft Academic Search

    BHARAT C. DIXIT; HITENDRA M. PATEL; DHIRUBHAI J. DESAI; RITU B. DIXIT

    Novel acid azo and mordent acid azo dyes have been prepared by the coupling of diazo solution of different aminonaphthol sulphonic acids and aromatic amino acids with 2,4-dihydroxybenzophenone. The resultant dyes were characterized by elemental analysis as well as IR and 1H NMR spectral studies. The UV-visible spectral data have also been discussed in terms of structure property relationship. The

  18. Dye-sensitized solar cells using natural dyes as sensitizers from Malaysia local fruit `Buah Mertajam'

    NASA Astrophysics Data System (ADS)

    Hambali, N. A. M. Ahmad; Roshidah, N.; Hashim, M. Norhafiz; Mohamad, I. S.; Saad, N. Hidayah; Norizan, M. N.

    2015-05-01

    We experimentally demonstrate the high conversion efficiency, low cost, green technology and easy to fabricate dye-sensitized solar cells (DSSCs) using natural anthocyanin dyes as sensitizers. The DSSCs was fabricated by using natural anthocyanin dyes which were extracted from different parts of the plants inclusive `Buah Mertajam', `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. The natural anthocyanin dyes that found in flower, leaves and fruits were extracted by the simple procedures. This anthocyanin dye is used to replace the expensive chemical synthetic dyes due to its ability to effectively attach into the surface of Titanium dioxide (TiO2). A natural anthocyanin dyes molecule adsorbs to each particle of the TiO2 and acts as the absorber of the visible light. A natural anthocyanin dye from Buah Mertajam shows the best performance with the conversion efficiency of 5.948% and fill factor of 0.708 followed by natural anthocyanin dyes from `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. Buah Mertajam or scientifically known as eriglossum rubiginosum is a local Malaysia fruit.

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

    PubMed

    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

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

    NASA Astrophysics Data System (ADS)

    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.

  1. Theoretical insight into the interaction between Gallium Di-Corrole dyes and iodine in dye-sensitized solar cells (DSCs)

    NASA Astrophysics Data System (ADS)

    Zhu, Chun; Liang, Jin-Xia

    2015-06-01

    The effects of iodine species on the performance of Gallium Di-Corrole (2-10-B1) dye in dye-sensitized solar cells have been investigated by density functional theory calculations. Calculations show that there are strong interactions between iodine (I-, I2- or I3-) and 2-10-B1 dye, but weak interaction between iodine molecule (I2) and the dye. For these iodine ions, the most stable adsorption site of 2-10-B1 dye is the center metal Ga. When an iodine ion is adsorbed on Ga atom of 2-10-B1 dye, the charge of the dye is better separated. Moreover, partial negative charge of iodine ion is transferred to the dye to facilitate the dye regeneration. And the absorption spectrum of the dye is broadened and red-shifted.

  2. Structural identification and bioactivities of red-violet pigments present in Basella alba fruits.

    PubMed

    Lin, Shu-Mei; Lin, Bo-Hong; Hsieh, Wan-Mei; Ko, Huey-Jiun; Liu, Chi-Dong; Chen, Lih-Geeng; Chiou, Robin Y-Y

    2010-10-13

    Mature Basella alba L. fruit, with dark blue skin and deep red-violet flesh, is a potential source of natural colorants. Its pigment components and bioactivities deserve particular attention and investigation. In this study, fruit flesh was extracted with 80% methanol (containing 0.2% formic acid) and subjected to solid-phase extraction, semipreparative HPLC isolation, mass spectrophotometric analysis, and structural elucidation. The major red pigment was identified as gomphrenin I. Its quantity increased with the increase of fruit maturity. The gomphrenin I extract yield from ripe fruits was 36.1 mg/100 g of fresh weight. In addition to gomphrenin I, betanidin-dihexose and isobetanidin-dihexose were also detected. The antioxidant activities of gomphrenin I determined by Trolox equivalent antioxidant capacity (TEAC), ?,?-diphenyl-?-picrylhydrazyl (DPPH) radical scavenging activity, reducing power, and antioxidative capacity assays were equivalent to 534 ?M Trolox, 103 ?M butylated hydroxytoluene (BHT), 129 ?M ascorbic acid, and 68 ?M BHT at 180, 23, 45, and 181 ?M, respectively. The anti-inflammatory function was tested at concentrations of 25, 50, and 100 ?M in murine macrophages stimulated with lipopolysaccharide (LPS). The results revealed that gomphrenin I suppressed LPS-induced nitric oxide (NO) production in a dose-dependent manner and decreased PGE(2) and IL-1? secretions at the highest concentration tested. The transcriptional inhibitory activities of gomphrenin I on the expression of inflammatory genes encoding iNOS, COX-2, IL-1?, TNF-?, and IL-6 were also observed. It is of merit to identify gomphrenin I as a principal pigment of B. alba fruits and as a potent antioxidant and inflammatory inhibitor. These findings suggest that B. alba fruit is a rich source of betalains and has value-added potential for use in the development of food colorants and nutraceuticals. PMID:20839771

  3. Electrical conduction mechanisms and dielectric constants of nanostructured methyl violet 2B thin films

    NASA Astrophysics Data System (ADS)

    Zeyada, H. M.; Makhlouf, M. M.

    2015-06-01

    The uniform thin films of methyl violet 2B, MV2B, with thicknesses ranged from 96 to 300 nm, have been successfully prepared by spin coating technique. X-ray diffraction showed that the powder and pristine thin film of MV2B have amorphous structure. The amorphous pristine films become polymorphous nanocrystallites after annealing at 433 K. The electrical properties of MV2B thin films have been studied. There are a number of operational environments where the performance of MV2B thin films is likely to be affected significantly on their electrical properties and dielectric constants such as the differences of film thicknesses, temperatures and frequencies. It was found that the DC conductivity of MV2B films increases with increasing temperature. The extrinsic conduction mechanism is operating in temperature range of 288-360 K with activation energy of 0.16 eV, and the conduction in extrinsic region is explained via applying Mott model for variable range hopping. The intrinsic conduction mechanism is operating in temperatures >360 K with activation energy of 0.91 eV. The conduction in intrinsic region is explained by applying band to band transitions theory. The AC electrical conductivity and dielectric relaxation of MV2B thin films in the temperature range 365-473 K and in frequency range 0.1-100 kHz has been also studied. It has been shown that theoretical curves generated from correlated barrier hopping, CBH, model gives the best fitting with experimental results. Analysis of these results proved that conduction occurs by phonon-assisted hopping between localized states and it is performed by bipolaron hopping mechanism. The temperature and frequency dependence of both the real and imaginary parts of dielectric constant have been investigated.

  4. Jupiter's Equatorial Region in the Near-Infrared and Violet (Time set 2)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Mosaics of an equatorial 'hotspot' on Jupiter at 756 nanometers (top) and 410 nanometers (bottom). The mosaics cover an area of 34,000 kilometers by 11,000 kilometers. The dark region near the center of each mosaic is an equatorial 'hotspot' similar to the Galileo Probe entry site. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance.

    The 756 nanometer (nm) near-infrared continuum filter shows the features of Jupiter's main visible cloud deck. Light at 410 nm is affected by the sizes and compositions of cloud particles, as well as the trace chemicals that give Jupiter's clouds their colors. Near-infrared continuum images are used to study cloud patterns and motions. Violet images contain additional information about cloud color and cloud particles.

    North is at the top. The mosaics cover latitudes 1 to 10 degrees and are centered at longitude 336 degrees West. The smallest resolved features are tens of kilometers in size. These images were taken on December 17, 1996, at a range of 1.5 million kilometers by the Solid State Imaging system aboard NASA's Galileo spacecraft.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  5. Blue-Violet Laser Modification of Titania Treated Titanium: Antibacterial and Osteo-Inductive Effects

    PubMed Central

    Kawano, Takanori; Prananingrum, Widyasri; Ishida, Yuichi; Goto, Takaharu; Naito, Yoshihito; Watanabe, Megumi; Tomotake, Yoritoki; Ichikawa, Tetsuo

    2013-01-01

    Background Many studies on surface modifications of titanium have been performed in an attempt to accelerate osseointegration. Recently, anatase titanium dioxide has been found to act as a photocatalyst that expresses antibiotic properties and exhibits hydrophilicity after ultraviolet exposure. A blue-violet semiconductor laser (BV-LD) has been developed as near-ultraviolet light. The purpose of this study was to investigate the effects of exposure to this BV-LD on surface modifications of titanium with the goal of enhancing osteoconductive and antibacterial properties. Methods The surfaces of pure commercial titanium were polished with #800 waterproof polishing papers and were treated with anatase titania solution. Specimens were exposed using BV-LD (? = 405 nm) or an ultraviolet light-emitting diode (UV-LED, ? = 365 nm) at 6 mW/cm2 for 3 h. The surface modification was evaluated physically and biologically using the following parameters or tests: surface roughness, surface temperature during exposure, X-ray diffraction (XRD) analysis, contact angle, methylene blue degradation tests, adherence of Porphyromonas gingivalis, osteoblast and fibroblast proliferation, and histological examination after implantation in rats. Results No significant changes were found in the surface roughness or XRD profiles after exposure. BV-LD exposure did not raise the surface temperature of titanium. The contact angle was significantly decreased, and methylene blue was significantly degraded. The number of attached P. gingivalis organisms was significantly reduced after BV-LD exposure compared to that in the no exposure group. New bone was observed around exposed specimens in the histological evaluation, and both the bone-to-specimen contact ratio and the new bone area increased significantly in exposed groups. Conclusions This study suggested that exposure of titanium to BV-LD can enhance the osteoconductivity of the titanium surface and induce antibacterial properties, similar to the properties observed following exposure to UV-LED. PMID:24358355

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

    Microsoft Academic Search

    Sunsanee Komboonchoo; Thomas Bechtold

    2009-01-01

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

  7. Removal of dyes from water using chitosan hydrogel/SiO2 and chitin hydrogel/SiO2 hybrid materials obtained by the sol-gel method.

    PubMed

    Copello, Guillermo J; Mebert, Andrea M; Raineri, M; Pesenti, Mariela P; Diaz, Luis E

    2011-02-15

    This work describes the synthesis of chitosan hydrogel/SiO(2) and chitin hydrogel/SiO(2) hybrid mesoporous materials obtained by the sol-gel method for their use as biosorbents. Their adsorption capabilities against four dyes (Remazol Black B, Erythrosine B, Neutral Red and Gentian Violet) were compared in order to evaluate chitin as a plausible replacement for chitosan considering its efficiency and lower cost. Both chitin and chitosan were used in the form of hydrogels. This allowed full compatibility with the ethanol release from tetraethoxysilane. The hybrid materials were characterized by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), Nitrogen Adsorption Isotherms and (13)C solid-state Nuclear Magnetic Resonance. Adsorption experimental data were analyzed using Langmuir, Freundlich and Dubinin-Radushkevich isotherm models along with the evaluation of adsorption energy and standard free energy (?G(0)). The adsorption was observed to be pH dependent. The main mechanism of dye adsorption was found to be a spontaneous charge associated interaction, except for EB adsorption on chitin/SiO(2) matrix, which showed to involve a lower energy physical adsorption interaction. Aside from highly charged dyes the chitin containing matrix has similar or higher adsorption capacity than the chitosan one. PMID:21163576

  8. Thermal treatment of dyes from military munitions

    SciTech Connect

    NONE

    1996-09-01

    Los Alamos National Laboratory has developed thermal treatment equipment to treat Navy smoke and dye compounds. Navy smokes were burned in the Los Alamos Controlled Air Incinerator (CAI) in the early 1980s. These test results were used in the development of a portable system consisting of a Thermal Treatment Unit (TTU), feed preparation and pumping skid, utility skid, and control trailer. This equipment was started up at Navy facilities at China Lake, CA where several destruction removal efficiency tests were completed in 1993 burning smoke compositions. The equipment was set up at the Nevada Test Site (NTS) in 1996 where tests were completed burning green Navy spotting dyes. Operating and test results from the NTS efforts resulted in clearer understanding of equipment deficiencies, dye characteristics and composition, and secondary wastes generated. Future tests, scheduled for July, 1996 will demonstrate higher bum rates, better pH measurement and control, and stack emission test results for other colored dyes.

  9. Tested Demonstrations: Dyeing of Anodized Aluminum.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Provides a list of needed materials, required preparations, and instructions for demonstrating the dyeing of anodized aluminum. Discusses the chemistry involved and gives equations for reactions occurring at the anode and cathode. (JM)

  10. Determination of dyes in diesel fuels

    SciTech Connect

    Sweeney, E.G.; Schmidt, C.H.; Zimin, A.; Caputo, P.A.; Anderson, P.M.

    1994-10-01

    On November 24, 1993, the Internal Revenue Service issued a `Notice of Proposed Rule Making` relating taxation of on-road diesel fuels and policing by means of a dyeing program. Based on the proposed regulation, various qualitative and quantitative methods were developed by two laboratories to identify and determine concentration of various dyes in No. 1 and No. 2 diesel fuels. A simple qualitative method was devised which consists of extracting the dye out of the fuel and identifying dye composition by thin layer chromatography. Quantitative methods were also developed based on spectrophometric evaluation of dyed fuel. The quantitative methods are designed for use with low cost single beam spectrophometers. Independent results based on a nine terminal sampling program are included. 5 refs., 2 figs., 13 tabs.

  11. Solid state dye laser for medical applications

    NASA Astrophysics Data System (ADS)

    Aldag, Henry R.

    1994-06-01

    The development of solid state dye lasers could lead to a major breakthrough in the cost and compactness of a medical device. Advantages include: elimination of the flow system for the gain medium; ease with which to implement wavelength agility or the replacement of a degraded rod or sheet; and toxicity and flammability become a non-issue. Dye lasers have played a role in cardiology, dermatology, and urology. Of these cardiology is of interest to Palomar. The Palomar Model 3010 flashlamp-pumped dye laser medical device was used during phase 1 FDA clinical trials to break-up blood clots that cause heart attacks, a process known as coronary laser thrombolysis. It is the objective of this research and development effort to produce solid matrix lasers that will replace liquid dye lasers in these medical specialties.

  12. Interaction between lyotropic chromonic liquid crystals and polymers

    NASA Astrophysics Data System (ADS)

    Yao, Xuxia; Park, Jung; Srinivasarao, Mohan

    2010-03-01

    Lyotropic chromonic liquid crystals (LCLCs) consist of various dyes, drugs, etc., so their importance is self-evident. The interaction of chromonic molecules and polymers is involved in their real applications, such as the dyeing process of fibers, textiles and food, and the functionalization of drugs in vivo. In our research, polymer dispersed LCLC droplets and polymer coated LCLC cells have been fabricated. Effect of interaction was observed by optical texture of LCLCs, as the different polymers induce different director configuration of LCLCs. A textile dye-Benzopurpurine 4B, food dye-Sunset Yellow FCF, and drug-Disodium Cromoglycate mixed with water soluble polymers, proteins and textile polymers have been all studied and compared.

  13. Effect of common reactive dye auxiliaries on the ozonation of dyehouse effluents containing vinylsulphone and aminochlorotriazine dyes

    Microsoft Academic Search

    Idil Arslan; Isil Akmehmet Balcioglu

    2000-01-01

    Ozonation of the commercially important reactive dyes Procion yellow HE4R (Reactive Yellow 84) and Remazol Black SB (Reactive Black 5) in actual dye rinse waters and simulated exhausted dye bath liquors has been studied. The effect of common dye auxiliaries (NaCl and Na2CO3) as well as the initial dye concentration on advanced oxidation kinetics was investigated. Decolourization was complete within

  14. Test strips detect different CO2 concentrations in closed compartments

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Four different test strips, using crystal violet for one pair of strips and basic fuchsin as a dye for the second pair, give unambiguous colorimetric indications of four different concentrations of carbon dioxide in the atmosphere of a closed compartment. Tetraethylene pentamine is used as a dye decoloring agent.

  15. Dye sensitized solar cells on paper substrates

    Microsoft Academic Search

    Bo Wang; Lei L. Kerr

    2011-01-01

    This article reports for the first time in the literature, a dye sensitized solar cells with 1.21% efficiency (Voc=0.56V, Jsc=6.70mA\\/cm2 and F.F.=0.33) on paper substrates. The current dye sensitized solar cell technology is based on fluorine doped SnO2 (FTO) coated glass substrates. The problem with the glass substrate is its rigidity and heavy weight. Making DSSCs on paper opens the

  16. Solid state dye lasers with scattering feedback

    NASA Astrophysics Data System (ADS)

    Costela, A.; Cerdán, L.; García-Moreno, I.

    2013-11-01

    Over the last decade, significant advances have been made toward the development of practical, tunable solid state dye lasers, which resulted in improved lasing efficiency with reduced dye photodegradation. To achieve this goal, a “chemical” approach was followed, where attention was focused onto the particular dye/host interaction and compatibility, specifically choosing already existing hosts for a given dye, synthesizing new dyes and/or matrices, or chemically modifying existing ones. Nevertheless, this approach was limited by a single fact learnt from the experience: there is no universal matrix which optimizes the efficiency and photostability of all dyes. This limitation could be overcome by following a “physical” approach, where the emission properties of the active medium are tailored by means of physical and structural modifications of the dye host. Following this approach, in this paper recent theoretical and experimental work is reviewed where it is demonstrated that following a simultaneous “physical” and “chemical” approach to tailor the emission properties of the host materials for solid state dye lasers, may lead, under specific circumstances, to the improvement of both the laser efficiency and photostability. In particular, it is demonstrated that optical scattering is not always detrimental either to conventional bulk lasers (laser rods or colloidal suspensions) or to integrated devices, but may give place, on the contrary, to dramatic improvements in the laser operation of organic (hybrid) laser rods, and to alternative ways of obtaining laser light from integrated devices based on the phenomenon of coherent random lasing, where feedback is provided by light scattering in an appropriate medium, without the need to manufacture complex periodic structures in the substrate. The processing and pumping flexibility of these materials, together with their low cost and capability of efficient emission across the whole visible spectrum makes them very attractive for the fabrication and development of coherent light sources suitable for integration in optoelectronic and disposable spectroscopic and sensing devices.

  17. Decolorization of Azo Dyes by Immobilized Bacteria

    Microsoft Academic Search

    Rashmi Khan; Uttam Chand Banerjee

    \\u000a Synthetic organic dyes are essential for satisfying the ever growing demand in terms of quality, variety, and speed of coloration\\u000a of large number of substances. Because of the xenobiotic nature of dyes, they are toxicant to biological system and causes\\u000a serious damage to environment. Ever-increasing concerns about color in the effluent lead to the worldwide efforts to build\\u000a up effective

  18. Spectral broadening in a microdroplet dye laser

    NASA Astrophysics Data System (ADS)

    Knospe, Anders G.; Kwok, Alfred S.

    2004-05-01

    We have observed broadening of the lasing spectrum of 60-?m diameter micrdroplet dye lasers. The spectral width of microdroplet dye lasers consisting of Rhodamine 6G or Pyrromethene 597 is essentially constant when water is used as a solvent but broaden by >30% at high input-laser intensities when ethanol is used as solvent. Spectral broadening is preceded by stimulated Raman scattering of ethanol in the microdroplets as the input-laser intensity increases.

  19. Sweeteners, flavorings, and dyes in antibiotic preparations.

    PubMed

    Kumar, A; Weatherly, M R; Beaman, D C

    1991-03-01

    Even though a variety of adverse effects caused by sweeteners, flavorings, and dyes in susceptible individuals have been reported, there is no good single reference with information about these substances in pediatric antimicrobials. Data on sweeteners, flavorings, and dyes in 91 antimicrobial preparations were collected. Sucrose was present in 74 (85%) of 87 preparations, followed by saccharin in 30 (34%) preparations. Mannitol, lactose, and sorbitol were each present in 7 preparations. None of the preparations were free of sweeteners. Thirty-four (37%) of 91 preparations did not specify the flavoring content. While cherry was the most common flavoring used, there were 25 other flavorings. Thirteen different dyes and coloring agents were used in these antimicrobials. Red dye no. 40 was present in 45% of preparations. Tables detailing sweeteners, flavorings, and dyes in different groups of antimicrobials (amoxicillin, ampicillin, cephalosporins, erythromycin, penicillins, sulfonamides, and others) and adverse effects reported with these inert ingredients are presented. These tables should be helpful to physicians in selecting an antimicrobial containing a different sweetener and/or dye when an adverse reaction occurs. PMID:2000275

  20. Oxidative degradation of azo dyes using tourmaline.

    PubMed

    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 H?O? 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 O?(·-) 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. PMID:23876254

  1. 38.2 / V. Chigrinov 38.2: Azodye Aligning Layers for Liquid Crystal Cells

    E-print Network

    38.2 / V. Chigrinov 38.2: Azodye Aligning Layers for Liquid Crystal Cells Vladimir Chigrinov, Elena as the anchoring of the rubbed PI layer. VHR value of the photo-aligned LC cell was also found to be very high (98 The photo-induced alignment of liquid crystal onto a photochemical stable azo dye film is studied

  2. Compact Ozone Differential Absorption Lidar (DIAL) Transmitter Using Solid-State Dye Polymers

    NASA Technical Reports Server (NTRS)

    Jones, Alton L., Jr.; DeYoung, Russell J.; Elsayid-Ele, Hani

    2001-01-01

    A new potential DIAL laser transmitter is described that uses solid-state dye laser materials to make a simpler, more compact, lower mass laser system. Two solid-state dye laser materials were tested to evaluate their performance in a laser oscillator cavity end pumped by a pulsed Nd:YAG laser at 532 nm. The polymer host polymethyl-methacrylate was injected with a pyrromethene laser dye, PM 580, or PM 597. A narrowband laser oscillator cavity was constructed to produce visible wavelengths of 578 and 600 nm which were frequency doubled into the UV region (299 or 300 nm) by using a BBO crystal, resulting in a maximum energy of 11 mJ at a wavelength of 578 nm when pumped by the Nd:YAG laser at an energy of 100 mJ (532 nm). A maximum output energy of 378 microJ was achieved in the UV region at a wavelength of 289 nm but lasted only 2000 laser shots at a repetition rate of 10 Hz. The results are promising and show that a solid-state dye laser based ozone DIAL system is possible with improvements in the design of the laser transmitter.

  3. Pulsed Discharge Plasma over a Water Surface Induces Decoloration of Dyes

    NASA Astrophysics Data System (ADS)

    Wahyudiono; Machmudah, Siti; Goto, Motonobu

    2013-06-01

    It was well known that plasma can be defined as a partially ionized gas composed of ions, electrons and neutral species. Recently, plasma-water interaction has attracted growing interest as it may provide experimental chemists with a quite unique reaction medium. In this work, decoloration of dyes in water as a reaction media and the effects of various parameters with pulsed high-voltage discharge plasma are studied. Such as plasma applied under hydrothermal conditions generates high-energy electrons, ions, and radicals, which in turn may generate new reaction fields, leading to effective organic compounds oxidation for both homogeneous and heterogeneous reactions. Here, we utilize pulse discharge plasma over water surface to study the decoloration of Orange G, Orange II, Congo Red, and Naphthol Blue Black. They were directly fed as starting materials without additives. The experiments were conducted under argon atmospheric at 313 K using a batch type reactor. The products were directly analyzed by UV-Vis (ultra violet-visible) spectrophotometer V-550. The decoloration rate increased with increasing peak pulse voltage and pulse numbers, presumably due to the increased electric field energy. Based on these results, the present system may be promising.

  4. Dye laser amplifier including a specifically designed diffuser assembly

    DOEpatents

    Davin, James (Gilroy, CA); Johnston, James P. (Stanford, CA)

    1992-01-01

    A large (high flow rate) dye laser amplifier in which a continuous replened supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a relatively high flow rate and a specifically designed diffuser assembly for slowing down the flow of dye while, at the same time, assuring that as the dye stream flows through the diffuser assembly it does so in a stable manner.

  5. Influence of index contrast in two dimensional photonic crystal lasers

    Microsoft Academic Search

    Mette Marie Jørgensen; Sidsel Rübner Petersen; Mads Brøkner Christiansen; Thomas Buß; Cameron L. C. Smith; Anders Kristensen

    2010-01-01

    The influence of index contrast variations for obtaining single-mode operation and low threshold in dye doped polymer two dimensional photonic crystal (PhC) lasers is investigated. We consider lasers made from Pyrromethene 597 doped Ormocore imprinted with a rectangular lattice PhC having a cavity in the middle of the crystal structure. We demonstrate that the index contrast, neff,high\\/neff,low, is an essential

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

    PubMed

    Mohammadi, Narges; Wang, Feng

    2014-03-01

    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 and red-shifted absorption spectra for both of the new candidate dyes. In particular, the new S9-D1 dye is found to have significant reduced HOMO-LUMO energy gap, greater push-pull character and higher wavelengths of absorption when compared to the reference dye. Such findings suggest that the new dyes are promising and suitable for optoelectronic applications. PMID:24595721

  7. A ‘Magnetic’ Gram Stain for Bacterial Detection

    PubMed Central

    Budin, Ghyslain; Chung, Hyun Jung; Lee, Hakho

    2012-01-01

    Magnetic stain. Bacteria are often classified into Gram-positive and Gram-negative strains by their visual staining properties using crystal violet (CV), a triarylmethane dye. Here we show, that bioorthogonal modification of crystal violet with transcyclooctene (TCO) can be used to render Gram-positive bacteria magnetic with magneto-nanoparticles-Tetrazine (MNP-Tz). This allows for class specific automated magnetic detection, magnetic separation or other magnetic manipulations. PMID:22744868

  8. One-copper laccase-related enzyme from Marasmius sp.: purification, characterization and bleaching of textile dyes.

    PubMed

    Schückel, Julia; Matura, Anke; van Pée, Karl-Heinz

    2011-03-01

    In the culture filtrate of a Marasmius sp. strain isolated in Indonesia during a screening for fungi with the ability to decolorize textile dyes, two laccase-related enzymes (laccase-related enzyme I and II) were detected. Laccase-related enzyme I was purified to homogeneity by ion exchange and hydrophobic interaction chromatography. The native enzyme was shown to have a molecular mass of 53 kDa, an N-terminal amino acid sequence characteristically seen in laccases and an isoelectric point of pH 3.8. The enzyme accepts typical laccase substrates including 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), syringaldazine and guaiacol, but has no tyrosinase activity. The pH optimum is at pH 3.0 for ABTS and at 6.0 for syringaldazine and the enzyme is stable up to pH 10. The UV/vis spectrum of the laccase-related enzyme is non-typical for laccases and metal content analysis revealed that the enzyme contains only a single copper atom per enzyme molecule. This suggests that this enzyme could be related to the group of the so-called "white" laccases, however, no zinc or any other metal ion could be detected in this enzyme, suggesting that the enzyme is a unique laccase-related enzyme. Comparison of the bleaching activity of the whole fungus with that of the isolated laccase-related enzyme showed that this enzyme is the major bleaching enzyme produced by this Marasmius sp. strain and was able to bleach violet, red, orange and yellow dyes in addition to a number of blue dyes. PMID:22112912

  9. Violet Light Down-Regulates the Expression of Specific Differentiation Markers through Rhodopsin in Normal Human Epidermal Keratinocytes

    PubMed Central

    Kim, Hyoung-June; Son, Eui Dong; Jung, Ji-Yong; Choi, Hyun; Lee, Tae Ryong; Shin, Dong Wook

    2013-01-01

    Several recent reports have demonstrated that photoreceptors are expressed in human skin. The rod and cone photoreceptor-like proteins are expressed in human skin and rhodopsin, long wavelength-opsin, and short wavelength-opsin are also present in cultured murine melanocytes. Furthermore, the photopigment rhodopsin is expressed in human melanocytes and is involved in ultraviolet A phototransduction which induces early melanin synthesis. In this study, we investigated whether rhodopsin is expressed and plays any physiological roles in the normal human epidermal keratinocytes (NHEKs). We found that rhodopsin was expressed and localized on the plasma membrane in NHEKs, and only violet light among several wavelengths within the visible range significantly increased the expression of rhodopsin mRNA. We further found that rhodopsin over-expression decreased the mRNA expression levels of keratinocyte differentiation markers, such as keratin-1 and keratin-10, and violet light also decreased the mRNA expression levels of keratinocyte differentiation markers and these decreased expression levels were recovered by a rhodopsin-directed siRNA. Moreover, we further demonstrated that violet light significantly decreased the phosphorylation levels of cAMP responsive element-binding protein (CREB) and that it more effectively decreased the phosphorylation of CREB when rhodopsin was over-expressed. In addition, we observed that pertussis toxin, a G?i protein inhibitor, restored the rhodopsin-induced decrease in the differentiation markers in NHEKs. Taken together, these results suggest that rhodopsin down-regulates the expression levels of specific keratinocyte differentiation markers via the G?i signaling pathway in NHEKs. PMID:24069221

  10. WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 8. PHTHALOCYANINE DYES AND PIGMENTS

    EPA Science Inventory

    A preliminary study of the manufacture of phthalocyanine dyes and pigments was conducted to determine if process waste streams might contain hazardous material. The study first identifies the dyes and pigments that belong to this segment of the industry, the amounts produced, and...

  11. INVESTIGATION OF SELECTED DYE CARRIERS USED IN COMMERCIAL DYEING OF HYDROPHOBIC FIBERS

    EPA Science Inventory

    The report gives results of an evaluation of toxicities of dyebath discharges from atmospheric dyeing of polyester fiber/fabric with three commercial dye carriers: trichlorobenzine (TCB), biphenyl (BP), and 0-phenyl phenol (OPP). First, criteria were established to rank the prior...

  12. Status of natural dyes and dye-yielding plants in India

    Microsoft Academic Search

    R. Siva

    Although plants exhibit a wide range of co lours, not all of these pigments can be used as dyes. Some do not di ssolve in water, some cannot be adsor bed on-to fibres, whereas others fade when washed or exposed to air or sunlight. It remains a mystery, why plants reward us with vibrant dyes. India has a rich biodiversity

  13. Highly intense violet-blue light emission at room temperature in structurally disordered SrZrO3 powders

    NASA Astrophysics Data System (ADS)

    Longo, V. M.; Cavalcante, L. S.; de Figueiredo, A. T.; Santos, L. P. S.; Longo, E.; Varela, J. A.; Sambrano, J. R.; Paskocimas, C. A.; De Vicente, F. S.; Hernandes, A. C.

    2007-02-01

    Violet-blue photoluminescence was produced at room temperature in a structurally disordered SrZrO3 perovskite structure with a 350.7nm excitation line. The intensity of this emission was higher than that of any other perovskites previously studied. The authors discuss the role of structural order-disorder that favors the self-trapping of electrons and charge transference, as well as a model to elucidate the mechanism that triggers photoluminescence. In this model the wide band model, the most important events occur before excitation.

  14. Evaluation of the Effects of the Ultra-Violet Radiation of Antarctica on Bovine Corneas and Lenses by Raman Spectroscopy

    NASA Astrophysics Data System (ADS)

    Yamamoto, Tatsuyuki; Imura, Satoshi; Yamamoto, Naoyuki

    2010-08-01

    The Raman spectra of bovine corneas and lenses irradiated to the ultra violet radiation at Syowa station of Antarctica were observed. The bovine crystallin occurred photo-induced cataract by the exposure to the solar radiation of mid-summer at Antarctica. Photo-induced decrease of Raman signals assigned to Trp residues suggests that the structural change of crystallin is correlated with the decomposition of them. The Raman spectra of the collagen of cornea showed little change, however FT-IR measurements showed that the IamideII/IamideI decreased much by the exposure to the solar radiation of mid-summer at Antarctica.

  15. Characterizing volcanic emissions using ground-based infrared and ultra-violet camera systems (Invited)

    NASA Astrophysics Data System (ADS)

    Prata, F.; Kern, C.; Burton, M. R.; Platt, U.

    2013-12-01

    In the last few years ground-based imaging cameras operating in the infrared and ultra-violet wavebands have been deployed at volcanoes across the world to measure volcanic emissions. Novel UV fast-sampling (~1-10 hz) camera systems employing high quantum efficiency detectors, narrowband filters, and incorporating multiple cameras or filter wheels have been devised to characterize SO2 emissions from volcanoes. Infrared systems using uncooled microbolometer detectors, employing filter wheels carrying interference filters to isolate radiation in the 8-12 ?m waveband have also been developed to measure SO2 and ash particles. The advantages and limitations of these systems for characterizing volcanic emissions are explored here. UV systems have superior accuracy for measuring SO2 fluxes compared to IR systems, while IR systems can measure in low light conditions and at night and can identify ash particles in the presence of SO2 gas. Calibration procedures differ markedly between the two systems and we describe how these can be done in a systematic and uniform manner so that retrieved parameters can be compared. The retrieval algorithms are also described and a common protocol is suggested for the more widely used UV camera systems. The important aspects of the radiative transfer for UV and IR light are compared and contrasted, and limitations are highlighted. Of the many useful aspects that these systems offer to volcanology, the ability to monitor emissions in real-time, at high sampling rates continuously is perhaps the most valuable. We show that such data can be incorporated into plume dispersion models to forecast the movement of hazardous ash and gas, provide timely warnings of increased activity at remote and dangerous volcanoes, and also be used to validate satellite-based retrievals of ash and SO2. These new camera systems are not yet standardized for volcanology as they are undergoing rapid development at a time when the enabling technology is also rapidly improving. There is still much to be learned and discovered concerning the optimal way to utilize these systems at volcanoes and on how the data can be combined with other types of measurements, e.g. seismic and infrasound, to provide improved monitoring of volcanic emissions.

  16. Molecular design and photovoltaic performance of organic dyes containing phenothiazine for dye-sensitized solar cells.

    PubMed

    Jo, Hyo Jeong; Nam, Jung Eun; Sim, Kyoseung; Kim, Dae-Hwan; Kim, Jae Hong; Kang, Jin-Kyu

    2014-10-01

    We synthesized novel organic photosensitizers based on fluorine-substituted phenothiazine with thiophene bridge units in the chromophore for application in dye-sensitized solar cells (DSSCs). Furthermore, organic dyes with different acceptors exhibited higher molar extinction coefficients, and better light absorption at longer wavelengths. The photovoltaic properties of organic dyes composed of different acceptors in their chromophores were measured to identify their effects on the DSSC performance. The organic dye, PFSCN2 containing multi-cyanoacrylic acid as the electron acceptor, showed a power conversion efficiency of 4.67% under AM 1.5 illumination (100 mW/cm2). The retarded recombination kinetics from TiO2 electrode to electrolyte enhanced the electron life time of the organic dye, PFSCN2 in the photoanode of the DSSC. This was confirmed with impedance analysis. PMID:25942898

  17. Fiber optics interface for a dye laser oscillator and method

    DOEpatents

    Johnson, Steve A. (Tracy, CA); Seppala, Lynn G. (Pleasanton, CA)

    1986-01-01

    A dye laser oscillator in which one light beam is used to pump a continuous tream of dye within a cooperating dye chamber for producing a second, different beam is generally disclosed herein along with a specific arrangement including an optical fiber and a fiber optics interface for directing the pumping beam into the dye chamber. The specific fiber optics interface illustrated includes three cooperating lenses which together image one particular dimension of the pumping beam into the dye chamber from the output end of the optical fiber in order to insure that the dye chamber is properly illuminated by the pumping beam.

  18. Fiber optics interface for a dye laser oscillator and method

    DOEpatents

    Johnson, S.A.; Seppala, L.G.

    1984-06-13

    A dye laser oscillator in which one light beam is used to pump a continuous stream of dye within a cooperating dye chamber for producing a second, different beam is generally disclosed herein along with a specific arrangement including an optical fiber and a fiber optics interface for directing the pumping beam into the dye chamber. The specific fiber optics interface illustrated includes three cooperating lenses which together image one particular dimension of the pumping beam into the dye chamber from the output end of the optical fiber in order to insure that the dye chamber is properly illuminated by the pumping beam.

  19. Unexpected radiation hazard in dyes of textiles.

    PubMed

    Abdel Ghany, Hayam A; Ibrahim, Eman M

    2014-01-01

    Textile dyes are among the most problematic pollutants because of their toxicity on several organisms and ecosystems. Many of the chemicals used in the textile industry may represent some health concerns. The determination of the radioactivity in textile dyes is therefore very important for both human health and environment. The study was designated to determine, for the first time, the values of (238)U, (232)Th and (40)K in nine different dyes employed in the textile industry using gamma spectrometry with a Hyper Pure Germanium (HPGe) detector. The mean activity concentrations of (238)U, (232)Th and (40)K were 29.37?±?4.48, 1.15?±?0.13 and 565?±?4 Bq/kg, respectively. The calculated radium equivalents for all samples were lower than the maximum admissible value (370 Bq/kg). The absorbed dose rates due to the natural radioactivity of the investigated samples ranged from 2.94?±?0.05 to 166?±?3 nGy/h. So, the absorbed dose rates for all samples of textile dyes were lower than the international recommended value (55 nGy/h) except the yellow dye (166?±?3 nGy/h), which recorded a significant radiological hazard. The external hazard index was also calculated. Conclusively, the results have indicated that the textile dyes may possess a measurable amount of radioactivity that should be taken into account. Therefore, safety rules and precautions should be applied for dyes used in the textile industry and for people working in this field. PMID:25322918

  20. Synthesis and characterization of Mg-based amorphous alloys and their use for decolorization of Azo dyes

    NASA Astrophysics Data System (ADS)

    Iqbal, M.; Wang, W. H.

    2014-06-01

    Mg-based alloys are light weight and have wide range of applications in the automotive industry. These alloys are widely used because of their very attractive physical and mechanical properties and corrosion resistance. The properties and applications can be further improved by changing the nature of materials from crystalline to amorphous. In this study, melt spun ribbons (MSRs) of Mg70Zn25Ca5 Mg68Zn27Ca5 alloys were prepared by melt spinning technique by using 3-4N pure metals. Characterization of the samples was done by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and energy dispersive x-ray analyzer (EDAX). Microstructural investigations were conducted by using scanning electron microscopy (SEM), atomic force microscopy (AFM) as well as optical and stereo scan microscopy techniques. DSC results showed multistage crystallization. Activation energy was found to be 225 kJ/mol by Kissinger method indicating good thermal stability against crystallization. XRD, DSC, SEM and EDS (energy dispersive spectroscopy) results are agreed very well. In order to study decolorization, the MSRs of Mg70Zn25Ca5 Mg68Zn27Ca5 alloys were treated repeatedly with various azo dyes at room temperature. In order to compare the results, MSRs of amorphous Zr- and Ni-based metallic glasses were also treated. Reaction of MSRs with azo dyes results in their decolorization in a few hours. Decolorization of azo dyes takes place by introducing amorphous MSRs which results in breaking the -N=N- bonds that exist in dye contents. It is concluded that Mg-based alloys are useful for paint and dye industries and will be beneficial to control water pollution. Comparison of results showed that Mg-based alloys are more efficient than Zr- and Ni-based amorphous alloys for decolorization of azo dyes.