Science.gov

Sample records for carmine organic dyes

  1. Indigo Carmine Dye-Polymer Nanocomposite Films For Optical Limiting Applications

    NASA Astrophysics Data System (ADS)

    Sreeja, S.; Mayadevi, S.; Suresh, S. R.; Frobel, P. G. Louie; Smijesh, N.; Philip, Reji; Muneera, C. I.

    2011-10-01

    Nanocomposite films of an organic dye-polymer (Indigo Carmine-PVA) system were fabricated and their optical limiting behaviour was investigated under excitation with 532 nm laser pulses of 5 ns temporal width using the open aperture Z-scan technique. The samples displayed optical limiting behavior under the experimental conditions. The Atomic Force Microscopic (AFM) analysis of the surface topography revealed homogeneous distribution of nanoclustered aggregates grown within the polymer matrix and an average roughness of ˜2.02 nm for the surface. The estimated values of the effective nonlinear absorption coefficient, ?eff (˜10-7-10-8 cm/W) marked up to the highest reported ones in literature in the nanosecond regime. The results indicate that these nanocomposite films are potential materials for optical limiting devices used for the protection of human eyes and other delicate optical sensors from laser induced optical damage.

  2. Determination of carmine food dye (E120) in foodstuffs by stripping voltammetry.

    PubMed

    Alghamdi, Ahmad H; Alshammery, Hamed M; Abdalla, Mohamed A; Alghamdi, Ali F

    2009-01-01

    The behavior of the food colorant agent carmine (E120) was studied by square-wave adsorptive stripping voltammetry (SW-AdSV) at the hanging mercury drop electrode. It was observed that carmine gave a sensitive stripping voltammetric peak at -350 mV in pH 3 acetate buffer. The cyclic voltammetric technique was also used to characterize the electrochemical reduction process of carmine. The adsorptive voltammetric signal was evaluated with respect to various experimental conditions, and the optimized values were supporting electrolyte, acetate buffer; buffer acidity, pH 3; dye concentration, 3 x 10(-7) M; accumulation time, 150 s; accumulation potential, -0.2 V; scan rate, 300 mV/s; pulse amplitude, 185 mV; SW frequency, 20 Hz; working electrode area, 0.6 mm2; and convection rate, 2600 rpm. The SW-AdSV peak currents depended linearly on the concentration of carmine from 5 x 10(-8) to 1.25 x 10(-7) mol/L (r = 0.99). A detection limit of 1.43 x 10(-9) mol/L with an RSD of 2.2% and a mean recovery of 97.9% were obtained. Possible interferences by several substances usually present in food products such as food additive dyes (E102, E100, E123, E127, and E129), artificial sweeteners, preservatives, and antioxidants were also evaluated. The proposed electrochemical procedure was successfully applied to the determination of carmine food dye in spiked commercially available ice cream and soft drinks. PMID:19916383

  3. An Indigo Carmine-Based Hybrid Nanocomposite with Supramolecular Control of Dye Aggregation and Photobehavior.

    PubMed

    Costa, Ana L; Gomes, Ana C; Pillinger, Martyn; Gonçalves, Isabel S; de Melo, J Sérgio Seixas

    2015-08-17

    Zn-Al layered double hydroxides (LDHs) containing solely indigo carmine (IC) or 1-hexanesulfonate (HS) anions, or a mixture of the two with different HS/IC molar ratios, were prepared by the direct synthesis method and characterized by various techniques. Hydrotalcite-type phases were obtained with basal spacings of 17.6?Å for the LDH intercalated by IC (IC-LDH) and 18.2-18.3?Å for the other materials containing HS. From the basal spacing for IC-LDH and UV/Vis spectroscopic data, it is proposed that the dye molecules assemble within the interlayer galleries to form a J-type stacking arrangement. A comprehensive electronic spectral and photophysical study was undertaken for IC in solution and all materials, aiming to obtain a detailed characterization of the host-guest and guest-guest interactions. In solution (the solvent surrounded "isolated" molecule), IC presents a fast excited state proton transfer with rate constants of ?1.2-1.4×10(11) ?s(-1) , which is linked to the very efficient radiationless deactivation channel. In the solid state it is shown that incorporation of IC within the LDH decreases the level of aggregation, and that further addition of HS induces the appearance of isolated IC units within the LDH galleries. The indigo carmine-based nanocomposites reported constitute a step forward in the design of hybrid materials with tunable properties. PMID:26216072

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

    NASA Astrophysics Data System (ADS)

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

    2012-03-01

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

  5. Anaphylaxis after ingestion of carmine colored foods: two case reports and a review of the literature.

    PubMed

    DiCello, M C; Myc, A; Baker, J R; Baldwin, J L

    1999-01-01

    Two patients with adverse food reactions to foods colored with carmine dye are presented, along with a review of the medical literature addressing adverse reactions to carmine colorant. This review summarizes the mounting evidence suggesting that adverse reactions to carmine colorant are the result of an IgE mediated mechanism. PMID:10624494

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

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

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

  7. 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...

  8. Continuous-wave organic dye lasers and methods

    DOEpatents

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

    2014-09-16

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

  9. Photophysical and electrochemical properties, and molecular structures of organic dyes for dye-sensitized solar cells.

    PubMed

    Ooyama, Yousuke; Harima, Yutaka

    2012-12-21

    Dye-sensitized solar cells (DSSCs) based on organic dyes adsorbed on oxide semiconductor electrodes, such as TiO(2), ZnO, or NiO, which have emerged as a new generation of sustainable photovoltaic devices, have attracted much attention from chemists, physicists, and engineers because of enormous scientific interest in not only their construction and operational principles, but also in their high incident-solar-light-to-electricity conversion efficiency and low cost of production. To develop high-performance DSSCs, it is important to create efficient organic dye sensitizers, which should be optimized for the photophysical and electrochemical properties of the dyes themselves, with molecular structures that provide good light-harvesting features, good electron communication between the dye and semiconductor electrode and between the dye and electrolyte, and to control the molecular orientation and arrangement of the dyes on a semiconductor surface. The aim of this Review is not to make a list of a number of organic dye sensitizers developed so far, but to provide a new direction in the epoch-making molecular design of organic dyes for high photovoltaic performance and long-term stability of DSSCs, based on the accumulated knowledge of their photophysical and electrochemical properties, and molecular structures of the organic dye sensitizers developed so far. PMID:22807392

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

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

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

  11. Can silicon substituted metal-free organic dyes achieve better efficiency compared to silicon free organic dyes? A computational study.

    PubMed

    Biswas, Abul Kalam; Das, Amitava; Ganguly, Bishwajit

    2015-11-18

    The power conversion efficiency of metal-free organic dyes in dye-sensitized solar cells (DSSCs) is now comparable to ruthenium-based polypyridyl and zinc-based porphyrin dyes. We have computationally investigated the structural, electronic and optical properties of a series of metal free organic dyes and their corresponding silicon substituted dyes. The DFT and TD-DFT calculations revealed that silicon substituted organic dyes have higher efficiency than the corresponding silicon free organic dyes. The computational results showed that the presence of silole units as a spacer group can significantly affect the performance of DSSCs compared to typically using thiophene as a spacer unit. These results corroborate the experimental observations reported in the literature. The time-dependent density functional theory (TDDFT) calculations performed at the CPCM-CAM-B3LYP/6-31+G* level of theory showed better agreement with the experimental absorption spectra of some reported metal free organic dyes having silole in the spacer group compared to other functionals and are employed in this study. Indoline donor based dye showed a much shorter absorption spectrum (absorption peak at 425 nm) and smaller electron injection driving force (?Ginjection = -1.77 eV) than the corresponding dye containing silicon substituted indoline as a donor and a silole group as a spacer unit. ?max = 502 nm and ?Ginjection = -1.82 eV calculated for dye are much larger than the corresponding silicon free dye . The silicon based dye helps in achieving a much lower ?Gregeneration value than , which can facilitate the faster electron injection rate from the dye to the semiconductor TiO2. Dye should also have a higher Voc value compared to other dyes () due to favourable interaction with the electrolyte (I(-)/I3(-)). The higher planarity and better conjugation in dye facilitate the transfer of electrons from the dye molecules to the semiconductor TiO2. The calculations performed with phenyl protecting groups near the silicon center of the dye molecule to diminish the dimerization process showed very similar optical properties as obtained with the corresponding unprotected dye system. The designed julolidine and pyrrolo-indolizine donor based dyes also showed a similar trend as observed for indoline donor based dyes. PMID:26535472

  12. Adsorption of cationic organic dyes in suspended-core fibers

    E-print Network

    Adsorption of cationic organic dyes in suspended-core fibers Barbara Wajnchold,1, * Michal Grabka,1 investigations reveal that the effect originates from the adsorption of the dye molecules on the fiber inner,7]. The mechanism of this phenomenon could be explained by chemical and/or physical adsorption. The adsorption

  13. Suspended-core optical fibres for organic dye absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Wajnchold, Barbara; Umi?ska, Ada; Grabka, Micha?; Kotas, Dariusz; Pustelny, Szymon; Gawlik, Wojciech

    2013-05-01

    In this paper, we report on our study of UV-VIS absorption spectroscopy in suspended-core optical fibres (SCFs) filled with organic-dye solutions. We compare two different dye classes, the anionic dye - bromophenol blue sodium salt (BB) and cationic dye - oxazine 725 perchlorate (OX). While the results obtained with BB are in a good agreement with the spectra measured in a standard reference cuvette, those obtained with OX are different and reveal much stronger absorption of light than in cuvettes. This stronger absorption indicates accumulation of the dye molecules on the short section of the core close to the end of the fibre. This observation demonstrates difference in physicochemical properties of the two dye classes and is important for the development of chemical sensors based on SCFs.

  14. Molecular dynamics simulations on the aggregation behavior of indole type organic dye molecules in dye-sensitized solar cells.

    PubMed

    Selvaraj, Ananda Rama Krishnan; Hayase, Shuji

    2012-05-01

    In Ti0(2) nanostructured dye-sensitized solar cells indole based organic dyes D149, D205 exhibits greater power conversion efficiency. Such organic dye molecules are easily undergone for aggregation. Aggregation in dye molecules leads to reduce electron transfer process in dye-sensitized solar cells. Therefore, anti-aggregating agents such as chenodeoxycholic acid are commonly added to organic dye solution in DSSCs. Studying aggregation of such dye molecules in the absence of semiconductors gives a detailed influence of anti-aggregating agents on dye molecules. Atomistic level of molecular dynamics (MD) simulations were performed on aggregation of indole type dye molecules D149, D205 and D205-F with anti-aggregating agent chenodeoxy cholic acid using AMBER program. The trajectories of the MD simulations were analyzed with order parameters such as radial atom pair distribution functions g(r), diffusion coefficients and root mean square deviations values. MD results suggest that addition of chenodeoxy cholic acid to dyes significantly reduces structural arrangement and increases conformational flexibility and mobility of dye molecules. The influence of semi-perfluorinated alkyl chains in indole dye molecules was analyzed. The parameters such as open-circuit voltage (V(oc)) and power conversion efficiency (?) of dye-sensitized solar cells are corroborated with flexibility and diffusion values of dye molecules. PMID:21904812

  15. Geometrical and energetical structural changes in organic dyes for dye-sensitized solar cells probed using photoelectron spectroscopy and DFT.

    PubMed

    Eriksson, Susanna K; Josefsson, Ida; Ellis, Hanna; Amat, Anna; Pastore, Mariachiara; Oscarsson, Johan; Lindblad, Rebecka; Eriksson, Anna I K; Johansson, Erik M J; Boschloo, Gerrit; Hagfeldt, Anders; Fantacci, Simona; Odelius, Michael; Rensmo, Håkan

    2016-01-01

    The effects of alkoxy chain length in triarylamine based donor-acceptor organic dyes are investigated with respect to the electronic and molecular surface structures on the performance of solar cells and the electron lifetime. The dyes were investigated when adsorbed on TiO2 in a configuration that can be used for dye-sensitized solar cells (DSCs). Specifically, the two dyes D35 and D45 were compared using photoelectron spectroscopy (PES) and density functional theory (DFT) calculations. The differences in solar cell characteristics when longer alkoxy chains are introduced in the dye donor unit are attributed to geometrical changes in dye packing while only minor differences were observed in the electronic structure. A higher dye load was observed for D45 on TiO2. However, D35 based solar cells result in higher photocurrent although the dye load is lower. This is explained by different geometrical structures of the dyes on the surface. PMID:26608268

  16. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and...restrictions. Carmine may be safely used in cosmetics generally, including cosmetics intended for use in the area of the eye,...

  17. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and...restrictions. Carmine may be safely used in cosmetics generally, including cosmetics intended for use in the area of the eye,...

  18. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and...restrictions. Carmine may be safely used in cosmetics generally, including cosmetics intended for use in the area of the eye,...

  19. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and...restrictions. Carmine may be safely used in cosmetics generally, including cosmetics intended for use in the area of the eye,...

  20. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and...restrictions. Carmine may be safely used in cosmetics generally, including cosmetics intended for use in the area of the eye,...

  1. Isotruxene-derived cone-shaped organic dyes for dye-sensitized solar cells.

    PubMed

    Lin, Shih-Hsun; Hsu, Ying-Chan; Lin, Jiann T; Lin, Cheng-Kai; Yang, Jye-Shane

    2010-11-19

    The synthesis, electronic properties, and performance in dye-sensitized solar cells (DSSCs) of four cone-shaped organic dyes (ITD, ITD-Th, ITD-Hx, and ITD-OM) containing the isotruxene ?-scaffold are reported. Selective substitution of the unsymmetrical isotruxene core with two diarylamino donors and one cyanocarboxylic acid acceptor was achieved by using a prefunctionalized dibromoisotruxene building block. The ortho-para-branched isotruxene core allows strong electronic couplings among the donors and the acceptor, leading to red-shifted absorption profiles with significant charge-transfer character. All four isotruxene dyes display reversible anodic waves in cyclic voltammagrams with both HOMO and LUMO potentials suitable for application in DSSCs. The DSSCs fabricated with these cone-shaped organic dyes exhibited high open-circuit voltages (0.67-0.76 V) and fill factors (0.67-0.72) with a power conversion efficiency (?) up to 5.45%, which is 80% of the ruthenium dye N719-based standard cell fabricated and measured under the same conditions. PMID:20973531

  2. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and specifications. The color...)(2). (b) Use and restrictions. Carmine may be safely used in cosmetics generally, including cosmetics... provisions of § 70.25 of this chapter. (2) Cosmetics containing carmine that are not subject to...

  3. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and specifications. The color...)(2). (b) Use and restrictions. Carmine may be safely used in cosmetics generally, including cosmetics... chapter. (2) Cosmetics containing carmine that are not subject to the requirements of § 701.3 of...

  4. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and specifications. The color...)(2). (b) Use and restrictions. Carmine may be safely used in cosmetics generally, including cosmetics... provisions of § 70.25 of this chapter. (2) Cosmetics containing carmine that are not subject to...

  5. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and specifications. The color...)(2). (b) Use and restrictions. Carmine may be safely used in cosmetics generally, including cosmetics... provisions of § 70.25 of this chapter. (2) Cosmetics containing carmine that are not subject to...

  6. 21 CFR 73.2087 - Carmine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2087 Carmine. (a) Identity and specifications. The color...)(2). (b) Use and restrictions. Carmine may be safely used in cosmetics generally, including cosmetics... provisions of § 70.25 of this chapter. (2) Cosmetics containing carmine that are not subject to...

  7. Comparison of triphenylamine based single and double branched organic dyes in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ahn, Hee Jin; Thogiti, Suresh; Cho, Jung Min; Jang, Bo Youn; Kim, Jae Hong

    2015-09-01

    A series of single and double branched organic dyes (1-4) utilizing two different acceptor groups, 2-cyanoacetic acid and rhodanine-3-acetic acid as anchoring moieties, were synthesized and characterized for their potential in dye sensitized solar cells (DSSCs). The DSSC based on sensitizer 3 has the best power conversion efficiency (3.51%) among all the devices assessed, which was 2 times higher than that of 1 with only one anchoring group. Compared to the 1-2 congeners with only one anchor, the dianchoring dyes 3-4 could suppress charge recombination more effectively and increase the electron injection efficiency, leading to a higher open-circuit voltage and short-circuit current. [Figure not available: see fulltext.

  8. The degradation of organic dyes by corona discharge

    SciTech Connect

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

    1992-02-01

    Several dyes in water were individually exposed to corona discharge. Light absorbance decreased for all organic dyes with time. Absorbance losses with methylene blue, malachite green, and new coccine were studied. The loss of color was followed using an in situ colorimeter and the effects of varying the current, voltage, gas phase, stirring rates, salinity, and electrode spacing were investigated. The highest reaction rates were observed using the highest current, highest voltage (up to 10kV), highest stirring rate, lowest salinity, smallest electrode spacing, and an environment containing enhanced levels of oxygen. Current was higher in the presence of nitrogen than in the presence of oxygen (for the same voltage), but the reaction of methylene blue did not proceed unless oxygen was present. These results help identify conditions using corona discharge in which dyes, and potentially other organics, can be destroyed. 22 refs., 5 figs.

  9. Organic dyes removal using magnetically modified rye straw

    NASA Astrophysics Data System (ADS)

    Baldikova, Eva; Safarikova, Mirka; Safarik, Ivo

    2015-04-01

    Rye straw, a very low-cost material, was employed as a biosorbent for two organic water-soluble dyes belonging to different dye classes, namely acridine orange (acridine group) and methyl green (triarylmethane group). The adsorption properties were tested for native and citric acid-NaOH modified rye straw, both in nonmagnetic and magnetic versions. The adsorption equilibrium was reached in 2 h and the adsorption isotherms data were analyzed using the Langmuir model. The highest values of maximum adsorption capacities were 208.3 mg/g for acridine orange and 384.6 mg/g for methyl green.

  10. TRANSIENT ABSORPTION AND STIMULATED EMISSION OF THE ORGANIC DYE "DISPERSE ORANGE 11"

    E-print Network

    Collins, Gary S.

    TRANSIENT ABSORPTION AND STIMULATED EMISSION OF THE ORGANIC DYE "DISPERSE ORANGE 11" By BRENT F this work. iii #12;TRANSIENT ABSORPTION AND STIMULATED EMISSION OF THE ORGANIC DYE "DISPERSE ORANGE 11 wavelength of 650nm is presented with the common organic dye 1-amino-2-methylanthraquinone (Disperse Orange

  11. Organics Verification Study for Sinclair and Dyes Inlets, Washington

    SciTech Connect

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

    2006-09-28

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

  12. Dynamic Characteristics of Aggregation Effects of Organic Dyes in Dye-Sensitized Solar Cells.

    PubMed

    Feng, Shuai; Li, Quan-Song; Sun, Ping-Ping; Niehaus, Thomas A; Li, Ze-Sheng

    2015-10-14

    Two organic dyes (LS-1 and IQ4) containing identical electron donor and acceptor units but distinct ? units result in significantly different power conversion efficiency of the corresponding dye-sensitized solar cells (DSSCs): LS-1, 4.4%, and IQ4, 9.2%. Herein, we combine first-principle calculations and molecular dynamics to explore the aggregation effects of LS-1 and IQ4 by comparing their optical properties and intermolecular electronic couplings. The calculated absorption spectra are in good agreement with the experimental observations and reveal them to be evidently affected by the dimerization. Furthermore, molecular dynamics simulations show that steric hindrance induced by the diphenylquinoxaline unit in IQ4 can elongate the distances between intermolecular ? units or electron donors, which are responsible for the fact that the intermolecular electronic coupling of LS-1 is about 10 times larger than that of IQ4. More importantly, the aggregated IQ4 remains almost perpendicular to the TiO2 surface, whereas LS-1 gradually tilts during the dynamic simulation, impacting electron injection and recombination in several ways, which clarifies why IQ4 leads to larger photocurrent and higher conversion efficiency. The deep understanding of the dye aggregation effects sheds new light on the complex factors determining DSSC function and paves the way for rational design of high-efficiency self-anti-aggregation sensitizers. PMID:26391331

  13. Photoproducts of carminic acid formed by a composite from Manihot dulcis waste.

    PubMed

    Antonio-Cisneros, Cynthia M; Dávila-Jiménez, Martín M; Elizalde-González, María P; García-Díaz, Esmeralda

    2015-04-15

    Carbon-TiO2 composites were obtained from carbonised Manihot dulcis waste and TiO2 using glycerol as an additive and thermally treating the composites at 800 °C. Furthermore, carbon was obtained from manihot to study the adsorption, desorption and photocatalysis of carminic acid on these materials. Carminic acid, a natural dye extracted from cochineal insects, is a pollutant produced by the food industry and handicrafts. Its photocatalysis was observed under different atmospheres, and kinetic curves were measured by both UV-Vis and HPLC for comparison, yielding interesting differences. The composite was capable of decomposing approximately 50% of the carminic acid under various conditions. The reaction was monitored by UV-Vis spectroscopy and LC-ESI-(Qq)-TOF-MS-DAD, enabling the identification of some intermediate species. The deleterious compound anthracene-9,10-dione was detected both in N2 and air atmospheres. PMID:25466082

  14. First principles study of organic sensitizers for dye sensitized solar cells: effects of anchoring groups on optoelectronic properties and dye aggregation.

    PubMed

    Nachimuthu, Santhanamoorthi; Chen, Wei-Chieh; Leggesse, Ermias Girma; Jiang, Jyh-Chiang

    2015-12-23

    We have designed a new set of D-?-A type organic dye sensitizers with different acceptor and anchoring groups, and systematically investigated their optoelectronic properties for efficient dye sensitized solar cell applications. Particularly, we have focused on the effects of anchoring groups on the dye aggregation phenomenon. TDDFT results indicate that the dyes with CSSH anchoring groups exhibit improved optoelectronic properties compared to other dyes. Further, molecular dynamics simulations have been performed to describe the formation of dye aggregation due to intermolecular hydrogen bonding. The observed results indicate that dyes with CSSH anchoring groups are less prone to aggregate because of their very weak intermolecular interactions. PMID:26661584

  15. POTENTIALLY TOXIC AND HAZARDOUS SUBSTANCES IN THE INDUSTRIAL ORGANIC CHEMICALS AND ORGANIC DYES AND PIGMENTS INDUSTRIES

    EPA Science Inventory

    The objective of this program were identification of the potential hazards associated with the production and use of industrial organic chemicals (IOC) and organic dyes and pigments (ODP) and determination of the state of the art of the control and treatment of potentially hazard...

  16. Organic Dye Behavior in PEG Block Copolymer Nanoparticles

    E-print Network

    Petta, Jason

    of light Measure the emission spectrum of the sample to determine dye behavior in the particles Nile red of block copolymers To find the optimal concentrations of fluorescent dyes in the nanoparticles To study(ethylene glycol)-b-poly(- caprolactone) #12;Fluorescent dyes Objective: Encapsulate fluorescent dyes

  17. Metal-free organic dyes for TiO2 and ZnO dye-sensitized solar cells.

    PubMed

    Selopal, Gurpreet Singh; Wu, Hui-Ping; Lu, Jianfeng; Chang, Yu-Cheng; Wang, Mingkui; Vomiero, Alberto; Concina, Isabella; Diau, Eric Wei-Guang

    2016-01-01

    We report the synthesis and characterization of new metal-free organic dyes (namely B18, BTD-R, and CPTD-R) which designed with D-?-A concept to extending the light absorption region by strong conjugation group of ?-linker part and applied as light harvester in dye sensitized solar cells (DSSCs). We compared the photovoltaic performance of these dyes in two different photoanodes: a standard TiO2 mesoporous photoanode and a ZnO photoanode composed of hierarchically assembled nanostructures. The results demonstrated that B18 dye has better photovoltaic properties compared to other two dyes (BTD-R and CPTD-R) and each dye has higher current density (Jsc) when applied to hierarchical ZnO nanocrystallites than the standard TiO2 mesoporous film. Transient photocurrent and photovoltage decay measurements (TCD/TVD) were applied to systematically study the charge transport and recombination kinetics in these devices, showing the electron life time (?R) of B18 dye in ZnO and TiO2 based DSSCs is higher than CPTD-R and BTD-R based DSSCs, which is consistent with the photovoltaic performances. The conversion efficiency in ZnO based DSSCs can be further boosted by 35%, when a compact ZnO blocking layer (BL) is applied to inhibit electron back reaction. PMID:26738698

  18. Interaction of protonated merocyanine dyes with amines in organic solvents

    NASA Astrophysics Data System (ADS)

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

    2011-10-01

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

  19. Organic Dyes with Well-Defined Structures for Highly Efficient Dye-Sensitised Solar Cells Based on a Cobalt Electrolyte.

    PubMed

    Seo, Kang Deuk; Choi, In Tack; Kim, Hwan Kyu

    2015-10-12

    Seven SGT organics dyes, containing bis-dimethylfluoreneyl amino groups with a dialkoxyphenyl unit as an electron donor and a cyanoacrylic acid group as an anchoring group, connected with oligothiophenes, fused thiophenes and benzothiadiazoles as ?-bridges, were designed and synthesised for applications in dye-sensitised solar cells (DSSCs). The photovoltaic performance of DSSCs based on organic dyes with oligothiophenes depends on the molecular structure of the dyes, in terms of the length change of the ?-bridging units. The best performance was found with a ?-bridge length of about 6?Å. To further enhance the photovoltaic performance associated with this concept, cyclopenta[1,2-b:5,4-b']dithiophene (CPDT) and benzothiadiazole were introduced into the ?-bridge unit. As a result, the DSSC based on the organic dye containing the CPDT moiety showed the best photovoltaic performance with a short-circuit photocurrent density (Jsc ) of 14.1?mA?cm(-2) , an open-circuit voltage (Voc ) of 0.84?V and a fill factor (FF) of 0.72, corresponding to an overall conversion efficiency (?) of 8.61?% under standard AM?1.5 irradiation. PMID:26332091

  20. Case study on the destruction of organic dyes in supercritical water

    SciTech Connect

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

    1994-11-01

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

  1. Benzo[a]carbazole-Based Donor-?-Acceptor Type Organic Dyes for Highly Efficient Dye-Sensitized Solar Cells.

    PubMed

    Qian, Xing; Zhu, Yi-Zhou; Chang, Wen-Ying; Song, Jian; Pan, Bin; Lu, Lin; Gao, Huan-Huan; Zheng, Jian-Yu

    2015-05-01

    A novel class of metal-free organic dyes based on benzo[a]carbazole have been designed, synthesized, and used in dye-sensitized solar cells for the first time. These types of dyes consisted of a cyanoacrylic acid moiety as the electron acceptor/anchoring group and different electron-rich spacers such as thiophene (JY21), furan (JY22), and oligothiophene (JY23) as the ?-linkers. The photophysical, electrochemical, and photovoltaic properties, as well as theoretical calculations of these dyes were investigated. The photovoltaic performances of these dyes were found to be highly relevant to the ?-conjugated linkers. In particular, dye JY23 exhibited a broad IPCE response with a photocurrent signal up to about 740 nm covering the most region of the UV-visible light. A DSSC based on JY23 showed the best photovoltaic performance with a Jsc of 14.8 mA cm(-2), a Voc of 744 mV, and a FF of 0.68, achieving a power conversion efficiency of 7.54% under standard AM 1.5 G irradiation. PMID:25874363

  2. Selective adsorption and separation of organic dyes from aqueous solution on polydopamine microspheres.

    PubMed

    Fu, Jianwei; Xin, Qianqian; Wu, Xuechen; Chen, Zhonghui; Yan, Ya; Liu, Shujun; Wang, Minghuan; Xu, Qun

    2016-01-01

    Polydopamine (PDA) microspheres, synthesized by a facile oxidation polymerization route, were evaluated as a potential adsorbent for selective adsorption and separation of organic dyes. The adsorption processes towards nine water-soluble dyes (anionic dyes: methyl orange (MO), eosin-Y (EY), eosin-B (EB), acid chrome blue K (ACBK), neutral dye: neutral red (NR), and cationic dyes: rhodamine B (RhB), malachite green (MG), methylene blue (MB), safranine T (ST)) were thoroughly investigated. The adsorption selectivity of organic dyes onto PDA microspheres was successfully applied for the separation of dyes mixtures. Various influential factors such as solution pH, temperature, and contact time were employed to ascertain the optimal condition for adsorption of representative organic dyes including MB, MG and NR. The pseudo-first-order and pseudo-second-order kinetics models were used to fit the adsorption kinetics process. Five isothermal adsorption models (Langmuir, Dubnin-Radushkevich, Temkin, Freundlich and Harkins-Jura) were used to investigate the adsorption thermodynamics properties. The results showed that the PDA microspheres owned good selective adsorption ability towards cationic dyes. The adsorption kinetics process conformed to the pseudo-second-order kinetics model and the Langmuir isotherm model was more appropriate for tracing the adsorption behavior than other isotherm models. Thus, we can conclude PDA microspheres may be a high-efficiency selective adsorbent towards some cationic dyes. PMID:26407057

  3. Advanced organic dye for high-speed, high-density optical media

    NASA Astrophysics Data System (ADS)

    Kodaira, Takuo; Matsuda, Isao; Somei, Hidenori; Tsuzuki, Takeo; Yokoyama, Daizo; Endo, Akihisa; Takeguchi, Kazunobu; Kojo, Shinichi; Miyazawa, Fuyuki; Otsu, Takeshi; Murai, Wakaaki; Hattori, Masashi; Shimomai, Kenichi; Oshita, Junji; Asano, Sho; Shimizu, Atsuo; Fujii, Toru

    2015-09-01

    Advances in organic dye progress are indispensable for high-speed, high-density recording of recordable Blu-ray Disc™ (BD-R) low-to-high (LTH) discs without a low elastic modulus layer. The optimal physical properties of the organic dyes, i.e., a low decomposition calorific value, a low decomposition temperature, and a large n-value, were determined, and a dye with these properties was synthesized. A BD-R disc using the dye conformed to the BD-R LTH standard at 8× recording and ever higher speeds should be possible. Furthermore, the possibility of 33 GB/layer high-density recording was suggested.

  4. Preparation and spectral characterization of polymeric nanocapsules containing DR1 organic dye

    NASA Astrophysics Data System (ADS)

    Sharifimehr, Mohammad Reza; Ghanbari, Khadijeh; Ayoubi, Kazem; Mohajerani, Ezedin

    2015-07-01

    In order to provide necessary degree of freedom for organic dye molecules in optical applications and also for safety improvement, water insoluble Disperse Red 1 (DR1) dye molecules were placed inside the polymeric nanocapsules along with suitable surfactants and using controlled phase-separation method. TEM images were used to investigate the morphology of prepared nanocapsules. Total dye concentration for a solution consist of obtained polymeric nanocapsules was determined using decomposition of nanocapsules and a reference absorption spectrum. Absorption spectrum of a solution containing DR1 and dichloromethane was also compared with prepared nanocapsules at the same dye concentration, thereby a red-shift in absorption spectrum was detected.

  5. White light-emitting diode with quasisolar spectrum based on organic fluorescent dyes

    NASA Astrophysics Data System (ADS)

    Chung, Shuang-Chao; Li, Ming-Chia; Sun, Ching-Cherng

    2015-07-01

    We present a study of light-emitting diodes (LEDs) using organic fluorescent dyes to replace the general phosphor. The blue die with a specific organic fluorescent dye gives the LED a single color appearance. Through a color-mixing cavity, multiple LEDs are used to produce a quasisolar spectrum at a certain band and white light with a color rendering index as high as 97 at around 2800 K.

  6. The electronic structure engineering of organic dye sensitizers for solar cells: The case of JK derivatives.

    PubMed

    Zhang, Cai-Rong; Ma, Jin-Gang; Zhe, Jian-Wu; Jin, Neng-Zhi; Shen, Yu-Lin; Wu, You-Zhi; Chen, Yu-Hong; Liu, Zi-Jiang; Chen, Hong-Shan

    2015-11-01

    The design and development of novel dye sensitizers are effective method to improve the performance of dye-sensitized solar cells (DSSCs) because dye sensitizers have significant influence on photo-to-current conversion efficiency. In the procedure of dye sensitizer design, it is very important to understand how to tune their electronic structures and related properties through the substitution of electronic donors, acceptors, and conjugated bridges in dye sensitizers. Here, the electronic structures and excited-state properties of organic JK dye sensitizers are calculated by using density functional theory (DFT) and time dependent DFT methods. Based upon the calculated results, we investigated the role of different electronic donors, acceptors, and ?-conjugated bridges in the modification of electronic structures, absorption properties, as well as the free energy variations for electron injection and dye regeneration. In terms of the analysis of transition configurations and molecular orbitals, the effective chromophores which are favorable for electron injection in DSSCs are addressed. Meanwhile, considering the absorption spectra and free energy variation, the promising electronic donors, ?-conjugated bridges, and acceptors are presented to design dye sensitizers. PMID:26116996

  7. Influence of selected fluorescent dyes on small aquatic organisms

    NASA Astrophysics Data System (ADS)

    Rowi?ski, Pawe?; Chrzanowski, Marcin

    2011-02-01

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

  8. Synthesis and Characterization of Organic Dyes Containing Various Donors and Acceptors

    PubMed Central

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

    2010-01-01

    New organic dyes comprising carbazole, iminodibenzyl, or phenothiazine moieties, respectively, as the electron donors, and cyanoacetic acid or acrylic acid moieties as the electron acceptors/anchoring groups were synthesized and characterized. The influence of heteroatoms on carbazole, iminodibenzyl and phenothiazine donors, and cyano-substitution on the acid acceptor is evidenced by spectral, electrochemical, photovoltaic experiments, and density functional theory calculations. The phenothiazine dyes show solar-energy-to-electricity conversion efficiency (?) of 3.46–5.53%, whereas carbazole and iminodibenzyl dyes show ? of 2.43% and 3.49%, respectively. PMID:20162019

  9. Effect of the co-sensitization sequence on the performance of dye-sensitized solar cells with porphyrin and organic dyes.

    PubMed

    Fan, Suhua; Lu, Xuefeng; Sun, Hong; Zhou, Gang; Chang, Yuan Jay; Wang, Zhong-Sheng

    2015-12-23

    To obtain a broad spectral response in the visible region, TiO2 film is co-sensitized with a porphyrin dye (FNE57 or FNE59) and an organic dye (FNE46). It is found that the stepwise co-sensitization in one single dye solution followed by in another single dye solution is better than the co-sensitization in a cocktail solution in terms of photovoltaic performance. The stepwise co-sensitization first with a porphyrin dye and then with an organic dye outperforms that in a reverse order. DSSC devices based on co-sensitizers FNE57 + FNE46 and FNE59 + FNE46 with a quasi-solid-state gel electrolyte generate power conversion efficiencies of 7.88% and 8.14%, respectively, which exhibits remarkable efficiency improvements of 61% and 35%, as compared with devices sensitized with the porphyrin dyes FNE57 and FNE59, respectively. Co-sensitization brings about a much improved short-circuit photocurrent due to the complementary absorption of the two sensitizers. The observed enhancement of incident monochromatic photon-to-electron conversion efficiency from individual dye sensitization to co-sensitization is attributed to the improved charge collection efficiency rather than to the light harvesting efficiency. Interestingly, the open-circuit photovoltage for the co-sensitization system comes between the higher voltage for the porphyrin dye (FNE57 or FNE59) and the lower voltage for the organic dye (FNE46), which is well correlated with their electron lifetimes. This finding indicates that not only the spectral complementation but also the electron lifetime should be considered to select dyes for co-sensitization. PMID:26651077

  10. 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.

  11. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... treatment to render the carmine and cochineal extract free of viable Salmonella microorganisms,...

  12. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... treatment to render the carmine and cochineal extract free of viable Salmonella microorganisms,...

  13. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... treatment to render the carmine and cochineal extract free of viable Salmonella microorganisms,...

  14. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... treatment to render the carmine and cochineal extract free of viable Salmonella microorganisms,...

  15. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... destroy all viable Salmonella microorganisms. Pasteurization or such other treatment is deemed to permit... treatment to render the carmine and cochineal extract free of viable Salmonella microorganisms,...

  16. Removal of organic dyes by magnetic alginate beads.

    PubMed

    Rocher, Vincent; Siaugue, Jean-Michel; Cabuil, Valérie; Bee, Agnès

    2008-02-01

    This study deals with the development of a clean and safe process for water pollution remediation. We have synthesized a magnetic adsorbent in order to develop a solid-phase extraction process assisted by a magnetic field. To follow an 'ecoconception' approach, magnetic beads containing magnetic nanoparticles and activated carbon are prepared with a biopolymer extracted from algae, sodium alginate. The use of renewable bioresources of low cost and those disposable in large amount allows the development of a product with a low impact on the environment. The adsorption properties of activated carbon and magnetic properties of iron oxide nanoparticles are combined to produce an interesting magnetic composite. Synthesis and characterization of the magnetic beads have been reported. Their adsorption capacity was investigated by measuring the removal of two dyes (methylene blue and methyl orange) of different charges from aqueous solutions. The efficiency of the beads has been compared with that of non-encapsulated activated carbon. The effects of initial dye concentration, pH and calcium content of the beads have been studied. Adsorption kinetics experiments have been carried out and the data have been well fitted by a pseudo-second-order equation. PMID:17980401

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

    ERIC Educational Resources Information Center

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

    2007-01-01

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

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

    ERIC Educational Resources Information Center

    Giglio, Kimberly D.; And Others

    1995-01-01

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

  19. Phosphorescent dyes for organic light-emitting diodes.

    PubMed

    Chou, Pi-Tai; Chi, Yun

    2007-01-01

    This article presents general concepts that have guided important developments in our recent research progress regarding room-temperature phosphorescent dyes and their potential applications. We first elaborate the theoretical background for emissive metal complexes and the strategic design of the chelating C-linked 2-pyridylazolate ligands, followed by their feasibility in functionalization and modification in an aim to fine-tune the chemical and photophysical properties. Subsequently, incorporation of 2-pyridylazolate chromophores is illustrated in the synthesis of the highly emissive, charge-neutral Os, Ru, Ir, and Pt complexes. Insights into their photophysical properties are gained from spectroscopy, relaxation dynamics, and theoretical approaches, from which the lowest-lying excited states, competitive radiative decay, and radiationless processes are then analyzed in detail. In view of applications, their potentials for OLEDs have been evaluated. The results, in combination with the fundamental basis, give a conceptual design contributed to the future advances in the field of OLEDs. PMID:17146830

  20. Effect of electron withdrawing unit for dye-sensitized solar cell based on D-A-?-A organic dyes

    SciTech Connect

    Kwon, Dong Yuel; Chang, Dong Min; Kim, Young Sik

    2014-10-15

    Highlights: • To gain the red-shifted absorption spectra, withdrawing unit was substituted in dye. • By the introduction of additional withdrawing unit, LUMOs level of dye are decreased. • Decreasing LUMOs level of dye caused the red-shifted absorption spectra of dye. • Novel acceptor, DCRD, showed better photovoltaic properties than cyanoacetic acid. - Abstract: In this work, two novel D-A-?-A dye sensitizers with triarylamine as an electron donor, isoindigo and cyano group as electron withdrawing units and cyanoacetic acid and 2-(1,1-dicyanomethylene) rhodanine as an electron acceptor for an anchoring group (TICC, TICR) were designed and investigated with the ID6 dye as the reference. The difference in HOMO and LUMO levels were compared according to the presence or absence of isoindigo in ID6 (TC and ID6). To gain insight into the factors responsible for photovoltaic performance, we used density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations. Owing to different LUMO levels for each acceptor, the absorption band and molar extinction coefficient of each dye was different. Among the dyes, TICR showed more red-shifted and broader absorption spectra than other dyes and had a higher molar extinction coefficient than the reference. It is expected that TICR would show better photovoltaic properties than the other dyes, including the reference dye.

  1. Observation of strong exciton photon coupling in semiconductor microcavities containing organic dyes and J-aggregates

    NASA Astrophysics Data System (ADS)

    Lidzey, D. G.; Virgili, T.; Bradley, D. D. C.; Skolnick, M. S.; Walker, S.; Whittaker, D. M.

    1999-06-01

    We report the observation of the strong-coupling regime between organic excitons and confined photons within a microcavity structure. As the optically active organic semiconductors within our devices, we have used the organic dye tetra-(2,6- tert-butyl)phenol-porphyrin zinc [4TBPPZn] which has an intense narrow "Soret" band absorption and also a cyanine dye which can form so-called "J-aggregates". Strong exciton-photon coupling is demonstrated from the anti-crossing of exciton and photon modes. Room temperature vacuum-Rabi splittings more than one order of magnitude larger than the highest values reported for inorganic semiconductors are observed. Such results open the way to structures in which new hybrid states of organic and inorganic excitons can be expected.

  2. 6H-Indolo[2,3-b]quinoxaline-based organic dyes containing different electron-rich conjugated linkers for highly efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Qian, Xing; Gao, Huan-Huan; Zhu, Yi-Zhou; Lu, Lin; Zheng, Jian-Yu

    2015-04-01

    A new class of organic dyes based on 6H-indolo[2,3-b]quinoxaline are synthesized and applied as photosensitizers for dye-sensitized solar cells. Different electron-rich ?-conjugated bridges such as oligothiophene, thienyl carbazole, and furyl carbazole are introduced to cooperate with 6H-indolo[2,3-b]quinoxaline and cyanoacrylic acid anchoring group to give the dyes JY01, JY02, and JY03, respectively. Their photophysical, electrochemical, and photovoltaic properties are further investigated. All three dyes show good performances as photosensitizers. In particular, DSSC based on JY01 shows the best photovoltaic performance with a short-circuit photocurrent density of 16.0 mA cm-2, an open-circuit photovoltage of 708 mV and a fill factor of 0.67, corresponding to an overall power conversion efficiency of 7.62% under AM 1.5 irradiation (100 mW cm-2).

  3. Phosphonic anchoring groups in organic dyes for solid-state solar cells.

    PubMed

    Abate, Antonio; Pérez-Tejada, Raquel; Wojciechowski, Konrad; Foster, Jamie M; Sadhanala, Aditya; Steiner, Ullrich; Snaith, Henry J; Franco, Santiago; Orduna, Jesús

    2015-07-28

    We report the synthesis and the optoelectronic characterization of three new 4H-pyran-4-ylidene and thiazole derivatives (pyt) as metal-free organic dyes for solid-state dye-sensitized solar cells (DSSCs). We investigate the performance and the long-term stability of devices employing pyt dyes functionalized with carboxylic and phosphonic acids as TiO2 anchoring groups. In contrast to reports on liquid electrolyte DSSCs, we show that solid-state DSSCs prepared with phosphoric pyt derivatives can achieve similar power conversion efficiency to their carboxyl analogues. We make use of the Mott-Schottky analysis and equivalent circuit models to demonstrate that a phosphonic group induces a significant increase in built-in voltage at the TiO2-hole transporter interface, which results in a higher open circuit voltage. PMID:26123840

  4. Synthesis of Pt3Ni Microspheres with High Performance for Rapid Degradation of Organic Dyes

    NASA Astrophysics Data System (ADS)

    Wang, Min; Yang, Yushi; Long, Jia; Mao, Zhou; Qiu, Tong; Wu, Qingzhi; Chen, Xiaohui

    2015-05-01

    In this study, Pt3Ni microspheres consisted of nanoparticles were synthesized without addition of surfactants via the solvothermal route. The obtained sample was characterized by X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometer (ICP-AES), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FESEM). Furthermore, the catalytic performance of as-synthesized Pt3Ni microspheres was evaluated on the degradation of different organic dyes (methylene blue, methyl orange, Congo red, and rhodamine B). The results show that different dyes were rapidly decomposed by Pt3Ni microspheres in different pathways. Among different dyes, the formation and further degradation of the intermediates was observed during the degradation of methylene blue and methyl orange, suggesting the indirect degradation process of these dyes. This study provides not only a promising catalyst for the removal of organic contaminants for environment remediation, but also new insights for Pt3Ni alloy as a high-performance catalyst in organic synthesis.

  5. Synthesis of Pt3Ni microspheres with high performance for rapid degradation of organic dyes.

    PubMed

    Wang, Min; Yang, Yushi; Long, Jia; Mao, Zhou; Qiu, Tong; Wu, Qingzhi; Chen, Xiaohui

    2015-12-01

    In this study, Pt3Ni microspheres consisted of nanoparticles were synthesized without addition of surfactants via the solvothermal route. The obtained sample was characterized by X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometer (ICP-AES), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FESEM). Furthermore, the catalytic performance of as-synthesized Pt3Ni microspheres was evaluated on the degradation of different organic dyes (methylene blue, methyl orange, Congo red, and rhodamine B). The results show that different dyes were rapidly decomposed by Pt3Ni microspheres in different pathways. Among different dyes, the formation and further degradation of the intermediates was observed during the degradation of methylene blue and methyl orange, suggesting the indirect degradation process of these dyes. This study provides not only a promising catalyst for the removal of organic contaminants for environment remediation, but also new insights for Pt3Ni alloy as a high-performance catalyst in organic synthesis. PMID:26058511

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

    PubMed

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

    2012-12-14

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

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

    NASA Astrophysics Data System (ADS)

    Joly, Damien; Pellejà, Laia; Narbey, Stéphanie; Oswald, Frédéric; Chiron, Julien; Clifford, John N.; Palomares, Emilio; Demadrille, Renaud

    2014-02-01

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

  8. A robust organic dye for dye sensitized solar cells based on iodine/iodide electrolytes combining high efficiency and outstanding stability.

    PubMed

    Joly, Damien; Pellejà, Laia; Narbey, Stéphanie; Oswald, Frédéric; Chiron, Julien; Clifford, John N; Palomares, Emilio; Demadrille, Renaud

    2014-01-01

    Among the new photovoltaic technologies, the Dye-Sensitized Solar Cell (DSC) is becoming a realistic approach towards energy markets such as BIPV (Building Integrated PhotoVoltaics). In order to improve the performances of DSCs and to increase their commercial attractiveness, cheap, colourful, stable and highly efficient ruthenium-free dyes must be developed. Here we report the synthesis and complete characterization of a new purely organic sensitizer (RK1) that can be prepared and synthetically upscaled rapidly. Solar cells containing this orange dye show a power conversion efficiency of 10.2% under standard conditions (AM 1.5G, 1000?Wm(-2)) using iodine/iodide as the electrolyte redox shuttle in the electrolyte, which is among the few examples of DSC using an organic dyes and iodine/iodide red/ox pair to overcome the 10% efficiency barrier. We demonstrate that the combination of this dye with an ionic liquid electrolyte allows the fabrication of solar cells that show power conversion efficiencies of up to 7.36% that are highly stable with no measurable degradation of initial performances after 2200?h of light soaking at 65°C under standard irradiation conditions. RK1 achieves one of the best output power conversion efficiencies for a solar cell based on the iodine/iodide electrolyte, combining high efficiency and outstanding stability. PMID:24504344

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

    PubMed Central

    Joly, Damien; Pellejà, Laia; Narbey, Stéphanie; Oswald, Frédéric; Chiron, Julien; Clifford, John N.; Palomares, Emilio; Demadrille, Renaud

    2014-01-01

    Among the new photovoltaic technologies, the Dye-Sensitized Solar Cell (DSC) is becoming a realistic approach towards energy markets such as BIPV (Building Integrated PhotoVoltaics). In order to improve the performances of DSCs and to increase their commercial attractiveness, cheap, colourful, stable and highly efficient ruthenium-free dyes must be developed. Here we report the synthesis and complete characterization of a new purely organic sensitizer (RK1) that can be prepared and synthetically upscaled rapidly. Solar cells containing this orange dye show a power conversion efficiency of 10.2% under standard conditions (AM 1.5G, 1000?Wm?2) using iodine/iodide as the electrolyte redox shuttle in the electrolyte, which is among the few examples of DSC using an organic dyes and iodine/iodide red/ox pair to overcome the 10% efficiency barrier. We demonstrate that the combination of this dye with an ionic liquid electrolyte allows the fabrication of solar cells that show power conversion efficiencies of up to 7.36% that are highly stable with no measurable degradation of initial performances after 2200?h of light soaking at 65°C under standard irradiation conditions. RK1 achieves one of the best output power conversion efficiencies for a solar cell based on the iodine/iodide electrolyte, combining high efficiency and outstanding stability. PMID:24504344

  10. Large area lighting applications with organic dye embedded flexible film

    NASA Astrophysics Data System (ADS)

    Lin, Huang-Yu; Tu, Zong-Yi; Ku, Pei-Cheng; Lin, Chien-Chung; Kuo, Hao-Chung

    2015-03-01

    A flexible large area lighting devices have been demonstrated by PDMS films. The (polydimethylsiloxane) PDMS films doped with organic/inorganic materials. The PDMS film is favorable due to its heat stability, good transparency, and flexibility. This study aimed to combine both organic and inorganic materials for flexible large area lighting applications. The architecture consists of blue LEDs coupled to a leaky waveguide that is covered with the PDMS film. The white light was generated with the poly (9, 9-dioctylfluorene-co-benzothiadiazole)F8BT blended into the PDMS slurry. Organic wavelength conversion materials were chosen owing to their ability to decompose in nature. The more conventional inorganic phosphors such as YAG are difficult to decompose and may present environmental issues which can bring concerns in many lighting applications. These flexible PDMS films had thicknesses of 100?m, 440?m, and 980?m. The resulting white light devices had color temperatures of 8944K, 4863K, and 4429K, respectively. In this study, we have also compared the performance of the organic versus conventional YAG phosphor embedded films.

  11. Degradation of organic dyes by Si/SiOx core-shell nanowires: Spontaneous generation of superoxides without light irradiation.

    PubMed

    Cao, Yu; Gu, Xiaoyu; Yu, Hongkun; Zeng, Wei; Liu, Xiang; Jiang, Suhua; Li, Yuesheng

    2016-02-01

    Recently, silicon nanowires (SiNWs) have been proven to be highly active in the photocatalysis of dye degradation. However, the unstable hydrogen-terminated surface and the need for constant light irradiation hinder their extensive use. In this work, a stable silica shell was intentionally formed on the surface of SiNWs to produce Si/SiOx core-shell silicon nanowires (S-SiNWs). Light-illuminated or not, S-SiNWs showed almost identical degradation ability for the degradation of indigo carmine (IC) in both conditions, which meant neither hydrogen termination nor light irradiation was a prerequisite for the degradation activity of S-SiNWs. UV/Vis spectroscopy and liquid chromatography/mass spectrometry showed that IC was converted into isatin sulfonic acid in this process. Quenching studies and electron paramagnetic resonance spectroscopy revealed that this bleaching ability was highly dependent on superoxides. A possible mechanism was accordingly suggested. In addition, the recently discovered reductase-like activity of SiNWs can be explained by the superoxides generation. PMID:26421622

  12. Theoretical analysis of the solvatochromism of organic dyes differing by the conjugation sequence

    NASA Astrophysics Data System (ADS)

    Manzhos, Sergei; Komatsu, Makoto; Nakazaki, Jotaro; Segawa, Hiroshi; Yamashita, Koichi

    2012-01-01

    Absorption peak maxima of two organic dyes differing by the position of the methine unit differ by 61 nm in dioxane and by up to 139 nm in polar solvents. It was previously reported that the difference is not reproduced by time-dependent density functional theory (TDDFT) using ab initio or hybrid functionals. TDDFT errors are different between the molecules, leading to a qualitative failure of TDDFT to predict relative energetics of the dyes. We focus on the effect of polar solvents (acetonitrile, DMSO, methanol, and 2-propanol) on the absorption spectrum, specifically, on the different between the two molecules sign of the solvatochromic shift versus dioxane. Using the correction due to Peach et al., the absolute TDDFT errors can be brought within acceptable ranges of 0.2 to 0.3 eV, and the blue shift versus dioxane is reproduced, although both dyes are predicted to exhibit positive solvatochromism. The inclusion of explicit solvent molecules did not appreciably change either TDDFT energies or the correction term. These results show that in dye design by changing the conjugation order, computational errors are expected to be more important than in the case of an extension of the size of conjugation, especially when polar solvents are used.

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

    PubMed

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

    2013-01-01

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

  14. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...shall be pasteurized or otherwise treated to destroy all viable Salmonella microorganisms. Pasteurization or such other treatment...to render the carmine and cochineal extract free of viable Salmonella microorganisms, which substances are not food...

  15. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...shall be pasteurized or otherwise treated to destroy all viable Salmonella microorganisms. Pasteurization or such other treatment...to render the carmine and cochineal extract free of viable Salmonella microorganisms, which substances are not food...

  16. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...shall be pasteurized or otherwise treated to destroy all viable Salmonella microorganisms. Pasteurization or such other treatment...to render the carmine and cochineal extract free of viable Salmonella microorganisms, which substances are not food...

  17. Tailoring of Energy Levels in D-?-A Organic Dyes via Fluorination of Acceptor Units for Efficient Dye-Sensitized Solar Cells

    PubMed Central

    Lee, Min-Woo; Kim, Jae-Yup; Son, Hae Jung; Kim, Jin Young; Kim, BongSoo; Kim, Honggon; Lee, Doh-Kwon; Kim, Kyungkon; Lee, Duck-Hyung; Ko, Min Jae

    2015-01-01

    A molecular design is presented for tailoring the energy levels in D-?-A organic dyes through fluorination of their acceptor units, which is aimed at achieving efficient dye-sensitized solar cells (DSSCs). This is achieved by exploiting the chemical structure of common D-?-A organic dyes and incorporating one or two fluorine atoms at the ortho-positions of the cyanoacetic acid as additional acceptor units. As the number of incorporated fluorine atoms increases, the LUMO energy level of the organic dye is gradually lowered due to the electron-withdrawing effect of fluorine, which ultimately results in a gradual reduction of the HOMO-LUMO energy gap and an improvement in the spectral response. Systematic investigation of the effects of incorporating fluorine on the photovoltaic properties of DSSCs reveals an upshift in the conduction-band potential of the TiO2 electrode during impedance analysis; however, the incorporation of fluorine also results in an increased electron recombination rate, leading to a decrease in the open-circuit voltage (Voc). Despite this limitation, the conversion efficiency is gradually enhanced as the number of incorporated fluorine atoms is increased, which is attributed to the highly improved spectral response and photocurrent. PMID:25591722

  18. Efficient organic sensitizers with pyridine-N-oxide as an anchor group for dye-sensitized solar cells.

    PubMed

    Wang, Lei; Yang, Xichuan; Zhao, Jianghua; Zhang, Fuguo; Wang, Xiuna; Sun, Licheng

    2014-09-01

    Five organic dyes with pyridine-N-oxide as the anchor group and electron acceptor have been synthesized and applied in dye-sensitized solar cells (DSSCs). Benzothiadiazole was introduced in the conjugation system to increase the electron withdrawing properties, FTIR spectra showed that the coordination was between the pyridine-N-oxide and the Brønsted acid site on the TiO2 surface. The relationship between different dye structures and the performance of the DSSCs was investigated systematically. The location of the thiophene unit was studied, and the direct linkage of benzothiadiazole with pyridine-N-oxide was beneficial to broaden the absorption. The donor-acceptor-acceptor-configured dye WL307, which has 2-ethylhexyloxy chains in the donor part, showed the best efficiency of 6.08% under 100?mW?cm(-2) light illumination. The dye series showed a fairly good stability during the one month test period. PMID:25066061

  19. Organic Dye 25 GB Write-Once Disk with In-Groove Structure

    NASA Astrophysics Data System (ADS)

    Nishiwaki, Hiroshi; Kitano, Kazutoshi; Nakajima, Hiroyuki; Muramatsu, Eiji; Taniguchi, Shoji; Inoue, Akiyoshi; Yokogawa, Fumihiko; Horie, Michikazu; Kiyono, Kenjirou; Miyazawa, Takashi; Kurose, Yutaka

    2006-02-01

    We have developed a new write-once disk technology, which is applicable to the Blu-ray disc system. An organic dye was adopted for the recording layer, which was optimized for the recording of the laser diode wavelength of 405 nm. We adopted a concave in-groove for the recording tracks to avoid thermal interference with adjacent recording tracks due to undesired and uneven dye pooling between adjacent tracks, considering the advantage of fabrication by spin-coating. We optimized the in-groove structure for low-to-high modulated recording. A sample disk, which was made by the conventional spin-coat process, showed good recording and readout characteristics with remarkably low cross-talk and cross-writing.

  20. 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.

  1. Enhanced anaerobic fermentation with azo dye as electron acceptor: simultaneous acceleration of organics decomposition and azo decolorization.

    PubMed

    Li, Yang; Zhang, Yaobin; Quan, Xie; Zhang, Jingxin; Chen, Shuo; Afzal, Shahzad

    2014-10-01

    Accumulation of hydrogen during anaerobic processes usually results in low decomposition of volatile organic acids (VFAs). On the other hand, hydrogen is a good electron donor for dye reduction, which would help the acetogenic conversion in keeping low hydrogen concentration. The main objective of the study was to accelerate VFA composition through using azo dye as electron acceptor. The results indicated that the azo dye serving as an electron acceptor could avoid H2 accumulation and accelerate anaerobic digestion of VFAs. After adding the azo dye, propionate decreased from 2400.0 to 689.5mg/L and acetate production increased from 180.0 to 519.5mg/L. It meant that the conversion of propionate into acetate was enhanced. Fluorescence in situ hybridization analysis showed that the abundance of propionate-utilizing acetogens with the presence of azo dye was greater than that in a reference without azo dye. The experiments via using glucose as the substrate further demonstrated that the VFA decomposition and the chemical oxygen demand (COD) removal increased by 319.7mg/L and 23.3% respectively after adding the azo dye. Therefore, adding moderate azo dye might be a way to recover anaerobic system from deterioration due to the accumulation of H2 or VFAs. PMID:25288539

  2. Rapid Synthesis of Thiophene-Based, Organic Dyes for Dye-Sensitized Solar Cells (DSSCs) by a One-Pot, Four-Component Coupling Approach.

    PubMed

    Matsumura, Keisuke; Yoshizaki, Soichi; Maitani, Masato M; Wada, Yuji; Ogomi, Yuhei; Hayase, Shuzi; Kaiho, Tatsuo; Fuse, Shinichiro; Tanaka, Hiroshi; Takahashi, Takashi

    2015-06-26

    This one-pot, four-component coupling approach (Suzuki-Miyaura coupling/C-H direct arylation/Knoevenagel condensation) was developed for the rapid synthesis of thiophene-based organic dyes for dye-sensitized solar cells (DSSCs). Seven thiophene-based, organic dyes of various donor structures with/without the use of a 3,4-ethylenedioxythiophene (EDOT) moiety were successfully synthesized in good yields based on a readily available thiophene boronic acid pinacol ester scaffold (one-pot, 3-step, 35-61%). Evaluation of the photovoltaic properties of the solar cells that were prepared using the synthesized dyes revealed that the introduction of an EDOT structure beside a cyanoacrylic acid moiety improved the short-circuit current (Jsc) while decreasing the fill factor (FF). The donor structure significantly influenced the open-circuit voltage (Voc), the FF, and the power conversion efficiency (PCE). The use of a n-hexyloxyphenyl amine donor, and our originally developed, rigid, and nonplanar donor, both promoted good cell performance (?=5.2-5.6%). PMID:26017569

  3. The study of synthetic food dyes by positron annihilation lifetime spectroscopy.

    NASA Astrophysics Data System (ADS)

    Pivtsaev, A. A.; Razov, V. I.

    2015-06-01

    By method of positron annihilation lifetime spectroscopy (PALS), substances are food dyes were studied: E-102 (Tartrazine), E-124 (Ponso 4R), E 132 (Indigo carmine), E-133 (Brilliant Blue), E-151 (Black Shiny). They are examined for the presence of carcinogenic properties. The difference between dyes having explicit carcinogenic properties and mutagenic properties (non-explicit carcinogens) is established.

  4. Cosensitization of D-A-?-A quinoxaline organic dye: efficiently filling the absorption valley with high photovoltaic efficiency.

    PubMed

    Pei, Kai; Wu, Yongzhen; Li, Hui; Geng, Zhiyuan; Tian, He; Zhu, Wei-Hong

    2015-03-11

    In the efficient cosensitization, the pure organic sensitizers with high molecular extinction coefficients and long wavelength response are highly preferable since the dye loading amount for each dye in cosensitization is decreased with respect to single dye sensitization. A D-A-?-A featured quinoxaline organic sensitizer IQ21 is specifically designed. The high conjugation building block of 4H-cyclopenta[2,1-b:3,4-b']dithiophene (CPDT) is introduced as the ? bridge, instead of the traditional thiophene unit, especially in realizing high molecular extinction coefficients (up to 66?600 M(-1) cm(-1)) and extending the light response wavelength. With respect to the reference dye IQ4, the slightly lower efficiency of IQ21 (9.03%) arises from the decrease of VOC, which offsets the gain in JSC. While cosensitized with a smaller D-?-A dye S2, the efficiency in IQ21 is further improved to 10.41% (JSC = 19.8 mA cm(-2), VOC = 731 mV, FF = 0.72). The large improvement in efficiency is attributed to the well-matched molecular structures and loading amounts of both dyes in the cosensitization system. We also demonstrated that coabsorbent dye S2 can distinctly compensate the inherent drawbacks of IQ21, not only enhancing the response intensity of IPCE, making up the absorption defects around low wavelength region of IPCE, but also repressing the charge recombination rate to some extent. PMID:25710618

  5. Influence of the donor size in D-?-A organic dyes for dye-sensitized solar cells.

    PubMed

    Yang, Jiabao; Ganesan, Paramaguru; Teuscher, Joël; Moehl, Thomas; Kim, Yong Joo; Yi, Chenyi; Comte, Pascal; Pei, Kai; Holcombe, Thomas W; Nazeeruddin, Mohammad Khaja; Hua, Jianli; Zakeeruddin, Shaik M; Tian, He; Grätzel, Michael

    2014-04-16

    We report two new molecularly engineered push-pull dyes, i.e., YA421 and YA422, based on substituted quinoxaline as a ?-conjugating linker and bulky-indoline moiety as donor and compared with reported IQ4 dye. Benefitting from increased steric hindrance with the introduction of bis(2,4-dihexyloxy)benzene substitution on the quinoxaline, the electron recombination between redox electrolyte and the TiO2 surface is reduced, especially in redox electrolyte employing Co(II/III) complexes as redox shuttles. It was found that the open circuit photovoltages of IQ4, YA421, and YA422 devices with cobalt-based electrolyte are higher than those with iodide/triiodide electrolyte by 34, 62, and 135 mV, respectively. Moreover, the cells employing graphene nanoplatelets on top of gold spattered film as a counter electrode (CE) show lower charge-transfer resistance compared to platinum as a CE. Consequently, YA422 devices deliver the best power conversion efficiency due to higher fill factor, reaching 10.65% at AM 1.5 simulated sunlight. Electrochemical impedance spectroscopy and transient absorption spectroscopy analysis were performed to understand the electrolyte influence on the device performances with different counter electrode materials and donor structures of donor-?-acceptor dyes. Laser flash photolysis experiments indicate that even though the dye regeneration of YA422 is slower than that of the other two dyes, the slower back electron transfer of YA422 contributes to the higher device performance. PMID:24655036

  6. Spatial modulation spectroscopy for imaging and quantitative analysis of single dye-doped organic nanoparticles inside cells

    NASA Astrophysics Data System (ADS)

    Devadas, Mary Sajini; Devkota, Tuphan; Guha, Samit; Shaw, Scott K.; Smith, Bradley D.; Hartland, Gregory V.

    2015-05-01

    Imaging of non-fluorescent nanoparticles in complex biological environments, such as the cell cytosol, is a challenging problem. For metal nanoparticles, Rayleigh scattering methods can be used, but for organic nanoparticles, such as dye-doped polymer beads or lipid nanoparticles, light scattering does not provide good contrast. In this paper, spatial modulation spectroscopy (SMS) is used to image single organic nanoparticles doped with non-fluorescent, near-IR croconaine dye. SMS is a quantitative imaging technique that yields the absolute extinction cross-section of the nanoparticles, which can be used to determine the number of dye molecules per particle. SMS images were recorded for particles within EMT-6 breast cancer cells. The measurements allowed mapping of the nanoparticle location and the amount of dye in a single cell. The results demonstrate how SMS can facilitate efforts to optimize dye-doped nanoparticles for effective photothermal therapy of cancer.Imaging of non-fluorescent nanoparticles in complex biological environments, such as the cell cytosol, is a challenging problem. For metal nanoparticles, Rayleigh scattering methods can be used, but for organic nanoparticles, such as dye-doped polymer beads or lipid nanoparticles, light scattering does not provide good contrast. In this paper, spatial modulation spectroscopy (SMS) is used to image single organic nanoparticles doped with non-fluorescent, near-IR croconaine dye. SMS is a quantitative imaging technique that yields the absolute extinction cross-section of the nanoparticles, which can be used to determine the number of dye molecules per particle. SMS images were recorded for particles within EMT-6 breast cancer cells. The measurements allowed mapping of the nanoparticle location and the amount of dye in a single cell. The results demonstrate how SMS can facilitate efforts to optimize dye-doped nanoparticles for effective photothermal therapy of cancer. Electronic supplementary information (ESI) available: TEM imaging, calibration experiments for the SMS instrument with gold nanoparticles, SMS images of dye doped polymer beads from a commercial source, evidence for endosome uptake, and additional SMS images of dye-doped LPNPs in EMT-6 cells, and spectra of SRfluor680/croconaine doped lipid-polymer nanoparticles. See DOI: 10.1039/C5NR01614B

  7. Third order optical nonlinearities characteristics of Disperse Red1 organic dye molecules inside of polymeric nanocapsules

    NASA Astrophysics Data System (ADS)

    Sharifimehr, Mohammad Reza; Ayoubi, Kazem; Mohajerani, Ezeddin

    2015-11-01

    Measuring nonlinear optical response of a specific material in a mixture, not only leads to investigate the behavior of a particular component in various circumstances, but also can be a way to select suitable combination and optimum concentration of additives and therefore obtaining the maximum nonlinear optical signals. In this work, by using dual-arm Z-scan technique, the nonlinear refractive index of Disperse Red1 (DR1) organic dye molecules inside the core of prepared polymeric nanocapsules was measured among various materials which prepared nanocapsules were made of them. Then the measured value was compared with nonlinear refractive index of DR1 solved in dichloromethane.

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

    PubMed

    Slade, Michael C; Raker, Jeffrey R; Kobilka, Brandon; Pohl, Nicola L B

    2014-01-14

    A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world. PMID:24501431

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

    PubMed Central

    2014-01-01

    A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world. PMID:24501431

  10. Sol-gel-derived silica films with tailored microstructures for applications requiring organic dyes

    SciTech Connect

    Logan, M.N.; Prabakar, S.; Brinker, C.J. |

    1994-09-01

    A three-step sol-gel process was developed to prepare organic dye-doped thin films with tailored porosity for applications in chemical sensing and optoelectronics. Varying the acid- and base-catalyzed hydrolysis steps of sols prepared from tetraethoxysilane with identical final H{sub 2}O/Si ratios, dilution factors and pH resulted in considerably different distributions of the silicate polymers in the sol (determined by {sup 29}Si NMR) and considerably different structures for the polymer clusters (determined by SAXS). During film formation these kinetic effects cause differences in the packing and collapse of the silicate network, leading to thin films with different refractive indices and volume fraction porosities. Under conditions where small pore-plugging species were avoided, the porosities of as-deposited films could be varied by aging the sol prior to film deposition. This strategy, which relies on the growth and aggregation of fractal polymeric clusters, is compatible with the low temperature and near neutral pH requirements of organic dyes.

  11. Preparation of ZnS-graphene nanocomposites under electric furnace and photocatalytic degradation of organic dyes.

    PubMed

    Park, Hae Soo; Ko, Weon Bae

    2014-11-01

    Zinc sulfide (ZnS) nanoparticles were synthesized from zinc nitrate hexahydrate and thiourea under microwave irradiation. The ZnS-graphene nanocomposites were calcined in an electric furnace at 700 degrees C under an inert argon gas atmosphere for 2 hr. The heated ZnS-graphene nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-vis spectrophotometry. After heat treatment, ZnS-graphene nanocomposites had a more porous and larger surface area, than the unheated ZnS-graphene nanocomposites. The photocatalytic activity of the heated ZnS-graphene nanocomposites in the degradation of organic dyes, such as methylene blue, methyl orange, and rhodamine B, under ultraviolet light at 254 nm by UV- vis spectrophotometer was evaluated and compared with that of the unheated ZnS nanoparticles, heated ZnS nanoparticles, unheated ZnS-graphene nanocomposites. Among the our experimental results as a photocatalyst, the heated ZnS-graphene nanocomposites exhibited remarkably higher photocatalytic degradation of organic dyes as compared to other nanomaterials such as unheated ZnS nanoparticles and heated ZnS-graphene nanocomposites. PMID:25958578

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

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

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

  13. Connecting Direct C-H Arylation Reactions with Dye-Sensitized Solar Cells: A Shortcut to D-A-?-A Organic Dyes.

    PubMed

    Lin, Po-Han; Lu, Te-Jui; Cai, Deng-Jhou; Lee, Kun-Mu; Liu, Ching-Yuan

    2015-10-01

    A step-economical synthetic strategy is developed to target thieno[3,4-c]pyrrole-4,6-dione (TPD)-based D-A-?-A organic dyes for dye-sensitized solar cells (DSSCs). Through sequential Pd-catalyzed direct C-H (hetero)arylation reaction, synthesis of the push-pull-type small molecules is reduced from the traditional six steps to two steps. In this report, we focus on the optimization of the key C-H monoarylation of TPD by screening ligands, acid additives, bases, and solvents. The reaction proves versatile toward new D-A-?-A organic dyes with a variety of different donor groups, and several derivatives are efficiently prepared under optimum reaction conditions. The sensitive aldehyde functionality that is a required intermediate for conversion into anchoring groups for TiO2 is well tolerated. Based on our synthetic study, DSSCs are fabricated and characterized using two designed sensitizers. The photovoltaic characterization of the devices affords an open-circuit voltage of 0.60-0.69?V, a short-circuit current density of 10.85-11.07?mA?cm(-2) , and a fill factor of 69.9-70.8?%, which corresponds to an overall power conversion efficiency of 4.61-5.33?%. PMID:26347029

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

    NASA Astrophysics Data System (ADS)

    Pramodini, S.; Poornesh, P.

    2014-11-01

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

  15. Tunable organic dye lasers: Physics and technology of high-performance liquid and solid-state narrow-linewidth oscillators

    NASA Astrophysics Data System (ADS)

    Duarte, F. J.

    2012-01-01

    Tunable organic dye lasers, usually referred simply as dye lasers, were the first broadly tunable lasers. Besides this awesome intrinsic feature, dye lasers emit directly in the visible spectrum and in their liquid state are uniquely suited to efficiently generate large pulsed average powers and large single-pulse energies. Other aspects of operational versatility include the ability to lase in the continuous wave (CW) regime and in the femtosecond-pulse regime. Consequently, organic dye lasers have served as pioneering vehicles for the development of essential laser physics. This is particularly true in the areas of tunable narrow-linewidth emission and femtosecond-laser emission. In this review we examine the essentials of cavity dispersion physics that make these emission modes possible, characteristics that have enabled a plethora of very successful and innovative applications. This review also examines developments in highly-efficient tunable single-longitudinal-mode organic solid-state dye lasers. A perspective on possible future trends, including miniature devices, is also provided.

  16. A novel porous anionic metal-organic framework with pillared double-layer structure for selective adsorption of dyes

    NASA Astrophysics Data System (ADS)

    Sheng, Shu-Nan; Han, Yi; Wang, Bin; Zhao, Cui; Yang, Fan; Zhao, Min-Jian; Xie, Ya-Bo; Li, Jian-Rong

    2016-01-01

    A novel porous anionic metal-organic framework, (Me2NH2)2[Zn2L1.5bpy]·2DMF (BUT-201; H4L=4,8-disulfonaphthalene-2,6-dicarboxylic acid; bpy=4,4-bipyridine; DMF=N,N-dimethylformamide), with pillared double-layer structure has been synthesized through the reaction of a sulfonated carboxylic acid ligand and Zn(NO3)2·6H2O with 4,4-bipyridine as a co-ligand. It is found that BUT-201 can rapidly adsorb cationic dyes with a smaller size such as Methylene Blue (MB) and Acriflavine Hydrochloride (AH) by substitution of guest (CH3)2NH2+, but has no adsorption towards the cationic dyes with a lager size such as Methylene Violet (MV), the anionic dyes like C. I. Acid Yellow 1 (AY1) and neutral dyes like C. I. Solvent Yellow 7 (SY7), respectively. The results show that the adsorption behavior of BUT-201 relates not only to the charge but also to the size/shape of dyes. Furthermore, the adsorbed dyes can be gradually released in the methanol solution of LiNO3.

  17. -encapsulated zero-valent iron nanoparticles for degradation of organic dyes

    NASA Astrophysics Data System (ADS)

    Mao, Zhou; Wu, Qingzhi; Wang, Min; Yang, Yushi; Long, Jia; Chen, Xiaohui

    2014-09-01

    A series of nanocomposites consisting of zero-valent iron nanoparticles (ZVI NPs) encapsulated in SiO2 microspheres were successfully synthesized through a successive two-step method, i.e., the wet chemical reduction by borohydride followed by a modified Stöber method. The as-synthesized nanocomposites were characterized using X-ray diffraction, field emission scanning electron microscopy, vibrating sample magnetometer, and inductively coupled plasma-atomic emission spectrometer. The catalytic performance of SiO2-encapsulated ZVI nanocomposites for the degradation of organic dyes was investigated using methylene blue (MB) as the model dye in the presence of H2O2. The results showed that the degradation efficiency and apparent rate constant of the degradation reaction were significantly enhanced with increased ZVI NPs encapsulated in SiO2 microspheres, whereas the dosage of H2O2 remarkably promoted degradation rate without affecting degradation efficiency. The content-dependent magnetic property ensured the excellent magnetic separation of degradation products under an external magnet. This strategy for the synthesis of SiO2-encapsulated ZVI NPs nanocomposites was low cost and easy to scale-up for industrial production, thereby enabling promising applications in environmental remediation.

  18. Molecular engineering of organic dyes with a hole-extending donor tail for efficient all-solid-state dye-sensitized solar cells.

    PubMed

    Lu, Jianfeng; Chang, Yu-Cheng; Cheng, Hsu-Yang; Wu, Hui-Ping; Cheng, Yibing; Wang, Mingkui; Diau, Eric Wei-Guang

    2015-08-10

    We report a new concept for the design of metal-free organic dyes (OD5-OD9) with an extended donor-?-acceptor (D-?-A) molecular framework, in which the donor terminal unit is attached by a hole-extending side chain to retard back electron transfer and charge recombination; the ?-bridge component contains varied thiophene-based substituents to enhance the light-harvesting ability of the device. The best dye (OD9) has a D-A-?-A configuration with the hexyloxyphenylthiophene (HPT) side chain as a hole-extension component and a benzothiadiazole (BTD) internal acceptor as a ?-extension component. The co-sensitization of OD9 with the new porphyrin dye LW24 enhanced the light-harvesting ability to 800?nm; thus, a power conversion efficiency 5.5?% was achieved. Photoinduced absorption (PIA) and transient absorption spectral (TAS) techniques were applied to account for the observed trend of the open-circuit voltage (VOC ) of the devices. This work provides insights into the molecular design, photovoltaic performance, and kinetics of charge recombination. PMID:26119886

  19. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...from an aqueous-alcoholic extract of cochineal (Dactylopius...food use made with cochineal extract or carmine may contain only...Specifications. (1) Cochineal extract shall conform to the following...more than 5.5 at 25 °C. Protein (N × 6.25), not more...

  20. 21 CFR 73.100 - Cochineal extract; carmine.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...from an aqueous-alcoholic extract of cochineal (Dactylopius...food use made with cochineal extract or carmine may contain only...Specifications. (1) Cochineal extract shall conform to the following...more than 5.5 at 25 °C. Protein (N × 6.25), not more...

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

    NASA Astrophysics Data System (ADS)

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

    2013-10-01

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

  2. Hierarchically porous silicon-carbon-nitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes

    NASA Astrophysics Data System (ADS)

    Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

    2015-01-01

    The hierarchically macro/micro-porous silicon-carbon-nitrogen (Si-C-N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7 mg.g-1 and 1084.5 mg.g-1 for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si-C-N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants.

  3. Hierarchically porous silicon-carbon-nitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes.

    PubMed

    Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

    2015-01-01

    The hierarchically macro/micro-porous silicon-carbon-nitrogen (Si-C-N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7?mg·g(-1) and 1084.5?mg·g(-1) for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si-C-N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants. PMID:25604334

  4. Hierarchically porous silicon–carbon–nitrogen hybrid materials towards highly efficient and selective adsorption of organic dyes

    PubMed Central

    Meng, Lala; Zhang, Xiaofei; Tang, Yusheng; Su, Kehe; Kong, Jie

    2015-01-01

    The hierarchically macro/micro-porous silicon–carbon–nitrogen (Si–C–N) hybrid material was presented with novel functionalities of totally selective and highly efficient adsorption for organic dyes. The hybrid material was conveniently generated by the pyrolysis of commercial polysilazane precursors using polydivinylbenzene microspheres as sacrificial templates. Owing to the Van der Waals force between sp2-hybridized carbon domains and triphenyl structure of dyes, and electrostatic interaction between dyes and Si-C-N matrix, it exhibites high adsorption capacity and good regeneration and recycling ability for the dyes with triphenyl structure, such as methyl blue (MB), acid fuchsin (AF), basic fuchsin and malachite green. The adsorption process is determined by both surface adsorption and intraparticle diffusion. According to the Langmuir model, the adsorption capacity is 1327.7?mg·g?1 and 1084.5?mg·g?1 for MB and AF, respectively, which is much higher than that of many other adsorbents. On the contrary, the hybrid materials do not adsorb the dyes with azo benzene structures, such as methyl orange, methyl red and congro red. Thus, the hierarchically porous Si–C–N hybrid material from a facile and low cost polymer-derived strategy provides a new perspective and possesses a significant potential in the treatment of wastewater with complex organic pollutants. PMID:25604334

  5. Organic acids enhanced decoloration of azo dye in gas phase surface discharge plasma system.

    PubMed

    Wang, Tiecheng; Qu, Guangzhou; Ren, Jingyu; Sun, Qiuhong; Liang, Dongli; Hu, Shibin

    2016-01-25

    A gas phase surface discharge plasma combined with organic acids system was developed to enhance active species mass transfer and dye-containing wastewater treatment efficacy, with Acid Orange II (AO7) as the model pollutant. The effects of discharge voltage and various organic acid additives (acetic acid, lactic acid and nonoic acid) on AO7 decoloration efficiency were evaluated. The experimental results showed that an AO7 decoloration efficiency of approximately 69.0% was obtained within 4min of discharge plasma treatment without organic acid addition, which was improved to 82.8%, 83.5% and 88.6% within the same treatment time with the addition of acetic acid, lactic acid and nonoic acid, respectively. The enhancement effects on AO7 decoloration efficiency could be attributed to the decrease in aqueous surface tension, improvement in bubble distribution and shape, and increase in ozone equivalent concentration. The AO7 wastewater was biodegradable after discharge plasma treatment with the addition of organic acid. AO7 decomposition intermediates were analyzed by UV-vis spectrometry and GC-MS; 2-naphthol, 1,4-benzoquinone, phthalic anhydride, coumarin, 1,2-naphthoquinone, and 2-formyl-benzoic acid were detected. A possible pathway for AO7 decomposition in this system was proposed. PMID:26444488

  6. Silver nanoparticles on amidoxime fibers for photo-catalytic degradation of organic dyes in waste water

    NASA Astrophysics Data System (ADS)

    Wu, Zhi-Chuan; Zhang, Yong; Tao, Ting-Xian; Zhang, Lifeng; Fong, Hao

    2010-11-01

    Herein we report that a new photo-catalyst of silver nanoparticles attached on the surface of amidoxime fibers was developed and evaluated. The nanoparticles had different sizes from tens to hundreds of nanometers and varied shapes of cube, plate, and sphere; and there were coordination interactions between the nanoparticles and the amidoxime fibers. The developed photo-catalyst demonstrated high activities for degradation of an organic dye of methyl orange, particularly under sunlight; and the catalyst could be re-activated for several times by simple tetrahydrofuran treatment. The results also suggested that the silver nanoparticles initiated and/or mediated the photo-oxidation reaction of methyl orange through localized surface plasmon resonance under sunlight, and the photo-catalytic activities were primarily determined by sizes and/or surface-to-mass ratios instead of shapes of the silver nanoparticles.

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

    NASA Astrophysics Data System (ADS)

    Manzhos, Sergei; Segawa, Hiroshi; Yamashita, Koichi

    2012-06-01

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

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

    SciTech Connect

    Nassar, Mostafa Y.; Ahmed, Ibrahim S.

    2012-09-15

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-05-01

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

  10. Photoconductivity of organic polymer films doped with porous silicon nanoparticles and ionic polymethine dyes

    SciTech Connect

    Davidenko, N. A. Skrichevsky, V. A.; Ishchenko, A. A.; Karlash, A. Yu.; Mokrinskaya, E. V.

    2009-05-15

    Features of electrical conductivity and photoconductivity of polyvinylbutyral films containing porous silicon nanoparticles and similar films doped with cationic and anionic polymethine dyes are studied. Sensitization of the photoelectric effect by dyes with different ionicities in films is explained by the possible photogeneration of holes and electrons from dye molecules and the intrinsic bipolar conductivity of porous silicon nanoparticles. It is assumed that the electronic conductivity in porous silicon nanoparticles is higher in comparison with p-type conductivity.

  11. Energy-Cascaded Upconversion in an Organic Dye-Sensitized Core/Shell Fluoride Nanocrystal.

    PubMed

    Chen, Guanying; Damasco, Jossana; Qiu, Hailong; Shao, Wei; Ohulchanskyy, Tymish Y; Valiev, Rashid R; Wu, Xiang; Han, Gang; Wang, Yan; Yang, Chunhui; Ågren, Hans; Prasad, Paras N

    2015-11-11

    Lanthanide-doped upconversion nanoparticles hold promises for bioimaging, solar cells, and volumetric displays. However, their emission brightness and excitation wavelength range are limited by the weak and narrowband absorption of lanthanide ions. Here, we introduce a concept of multistep cascade energy transfer, from broadly infrared-harvesting organic dyes to sensitizer ions in the shell of an epitaxially designed core/shell inorganic nanostructure, with a sequential nonradiative energy transfer to upconverting ion pairs in the core. We show that this concept, when implemented in a core-shell architecture with suppressed surface-related luminescence quenching, yields multiphoton (three-, four-, and five-photon) upconversion quantum efficiency as high as 19% (upconversion energy conversion efficiency of 9.3%, upconversion quantum yield of 4.8%), which is about ?100 times higher than typically reported efficiency of upconversion at 800 nm in lanthanide-based nanostructures, along with a broad spectral range (over 150 nm) of infrared excitation and a large absorption cross-section of 1.47 × 10(-14) cm(2) per single nanoparticle. These features enable unprecedented three-photon upconversion (visible by naked eye as blue light) of an incoherent infrared light excitation with a power density comparable to that of solar irradiation at the Earth surface, having implications for broad applications of these organic-inorganic core/shell nanostructures with energy-cascaded upconversion. PMID:26487489

  12. Development of a rapid and simple method for detection of protein contaminants in carmine.

    PubMed

    Nakayama, Norihisa; Ohtsu, Yutaka; Maezawa-Kase, Daisuke; Sano, Ken-Ichi

    2015-01-01

    Protein contaminants in carmine can cause dyspnea and anaphylactic reactions in users and consumers of products containing this pigment. The method generally used for detection of proteins in carmine has low reproducibility and is time-consuming. In this study, a rapid, simple, and highly reproducible method was developed for the detection of protein contaminants in carmine. This method incorporates acidic protein denaturation conditions and ultrafiltration. To prevent protein aggregation, sodium dodecyl sulfate containing gel electrophoresis running buffer was used for dispersing the carmine before filtration. An ultrafiltration device was used to separate the protein contaminants from carminic acid in the carmine solution. Two ultrafiltration devices were compared, and a cylindrical device containing a modified polyethersulfone membrane gave the best results. The method had high reproducibility. PMID:25892994

  13. Development of a Rapid and Simple Method for Detection of Protein Contaminants in Carmine

    PubMed Central

    Nakayama, Norihisa; Ohtsu, Yutaka; Maezawa-Kase, Daisuke; Sano, Ken-Ichi

    2015-01-01

    Protein contaminants in carmine can cause dyspnea and anaphylactic reactions in users and consumers of products containing this pigment. The method generally used for detection of proteins in carmine has low reproducibility and is time-consuming. In this study, a rapid, simple, and highly reproducible method was developed for the detection of protein contaminants in carmine. This method incorporates acidic protein denaturation conditions and ultrafiltration. To prevent protein aggregation, sodium dodecyl sulfate containing gel electrophoresis running buffer was used for dispersing the carmine before filtration. An ultrafiltration device was used to separate the protein contaminants from carminic acid in the carmine solution. Two ultrafiltration devices were compared, and a cylindrical device containing a modified polyethersulfone membrane gave the best results. The method had high reproducibility. PMID:25892994

  14. A metal-organic tetrahedron as a redox vehicle to encapsulate organic dyes for photocatalytic proton reduction.

    PubMed

    Jing, Xu; He, Cheng; Yang, Yang; Duan, Chunying

    2015-03-25

    The design of artificial systems that mimic highly evolved and finely tuned natural photosynthetic systems is a subject of intensive research. We report herein a new approach to constructing supramolecular systems for the photocatalytic generation of hydrogen from water by encapsulating an organic dye molecule into the pocket of a redox-active metal-organic polyhedron. The assembled neutral Co4L4 tetrahedron consists of four ligands and four cobalt ions that connect together in alternating fashion. The cobalt ions are coordinated by three thiosemicarbazone NS chelators and exhibit a redox potential suitable for electrochemical proton reduction. The close proximity between the redox site and the photosensitizer encapsulated in the pocket enables photoinduced electron transfer from the excited state of the photosensitizer to the cobalt-based catalytic sites via a powerful pseudo-intramolecular pathway. The modified supramolecular system exhibits TON values comparable to the highest values reported for related cobalt/fluorescein systems. Control experiments based on a smaller tetrahedral analogue of the vehicle with a filled pocket and a mononuclear compound resembling the cobalt corner of the tetrahedron suggest an enzymatic dynamics behavior. The new, well-elucidated reaction pathways and the increased molarity of the reaction within the confined space render these supramolecular systems superior to other relevant systems. PMID:25738748

  15. Accurate Diffusion Coefficients of Organosoluble Reference Dyes in Organic Media Measured by Dual-Focus Fluorescence Correlation Spectroscopy.

    PubMed

    Goossens, Karel; Prior, Mira; Pacheco, Victor; Willbold, Dieter; Müllen, Klaus; Enderlein, Jörg; Hofkens, Johan; Gregor, Ingo

    2015-07-28

    Dual-focus fluorescence correlation spectroscopy (2fFCS) is a versatile method to determine accurate diffusion coefficients of fluorescent species in an absolute, reference-free manner. Whereas (either classical or dual-focus) FCS has been employed primarily in the life sciences and thus in aqueous environments, it is increasingly being used in materials chemistry, as well. These measurements are often performed in nonaqueous media such as organic solvents. However, the diffusion coefficients of reference dyes in organic solvents are not readily available. For this reason we determined the translational diffusion coefficients of several commercially available organosoluble fluorescent dyes by means of 2fFCS. The selected dyes and organic solvents span the visible spectrum and a broad range of refractive indices, respectively. The diffusion coefficients can be used as absolute reference values for the calibration of experimental FCS setups, allowing quantitative measurements to be performed. We show that reliable information about the hydrodynamic dimensions of the fluorescent species (including noncommercial compounds) within organic media can be extracted from the 2fFCS data. PMID:26144863

  16. Preparation of graphene-ZrO2 nanocomposites by heat treatment and photocatalytic degradation of organic dyes.

    PubMed

    Cho, Bum Hwi; Ko, Weon Bae

    2013-11-01

    ZrO2 nanoparticles were synthesized by combining a solution containing zinconyl chloride in distilled water with a NH4OH solution under microwave irradiation. Graphene and ZrO2 nanocomposites were synthesized in an electric furnace at 700 degrees C for 2 hours. The heated graphene-ZrO2 nanocomposites were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. In addition, UV-vis spectrophotometry was used to evaluate the heated graphene-ZrO2 nanocomposites as a catalyst in the photocatalytic degradation of organic dyes. The photocatalytic effect of the heated graphene-ZrO2 nanocomposites was compared with that of unheated graphene nanoparticles, heated graphene nanoparticles, and unheated graphene-ZrO2 nanocomposites in organic dyes (methylene blue, methyl orange, and rhodamine B) under ultraviolet light at 254 nm. PMID:24245304

  17. Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaoli; Liu, Shuangliu; Tang, Zhi; Niu, Hongyun; Cai, Yaqi; Meng, Wei; Wu, Fengchang; Giesy, John P.

    2015-07-01

    A novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52?m2 g-1), excellent magnetic response (14.89?emu g-1), and large mesopore volume (0.09?cm3 g-1), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting ?-? stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84?mg MB g-1 at an initial MB concentration of 30?mg L-1, which increased to 245?mg g-1 when the initial MB concentration was 300?mg L-1. This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles.

  18. Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water

    PubMed Central

    Zhao, Xiaoli; Liu, Shuangliu; Tang, Zhi; Niu, Hongyun; Cai, Yaqi; Meng, Wei; Wu, Fengchang; Giesy, John P.

    2015-01-01

    A novel, simple and efficient strategy for fabricating a magnetic metal-organic framework (MOF) as sorbent to remove organic compounds from simulated water samples is presented and tested for removal of methylene blue (MB) as an example. The novel adsorbents combine advantages of MOFs and magnetic nanoparticles and possess large capacity, low cost, rapid removal and easy separation of the solid phase, which makes it an excellent sorbent for treatment of wastewaters. The resulting magnetic MOFs composites (also known as MFCs) have large surface areas (79.52?m2 g?1), excellent magnetic response (14.89?emu g?1), and large mesopore volume (0.09?cm3 g?1), as well as good chemical inertness and mechanical stability. Adsorption was not drastically affected by pH, suggesting ?–? stacking interaction and/or hydrophobic interactions between MB and MFCs. Kinetic parameters followed pseudo-second-order kinetics and adsorption was described by the Freundlich isotherm. Adsorption capacity was 84?mg MB g?1 at an initial MB concentration of 30?mg L?1, which increased to 245?mg g?1 when the initial MB concentration was 300?mg L?1. This capacity was much greater than most other adsorbents reported in the literature. In addition, MFC adsorbents possess excellent reusability, being effective after at least five consecutive cycles. PMID:26149818

  19. Incorporating hierarchical nanostructured carbon counter electrode into metal-free organic dye-sensitized solar cell.

    PubMed

    Fang, Baizeng; Fan, Sheng-Qiang; Kim, Jung Ho; Kim, Min-Sik; Kim, Minwoo; Chaudhari, Nitin K; Ko, Jaejung; Yu, Jong-Sung

    2010-07-01

    Hierarchical nanostructured carbon with a hollow macroporous core of ca. 60 nm in diameter in combination with mesoporous shell of ca. 30 nm in thickness has been explored as counter electrode in metal-free organic dye-sensitized solar cell. Compared with other porous carbon counterparts such as activated carbon and ordered mesoporous carbon CMK-3 and Pt counter electrode, the superior structural characteristics including large specific surface area and mesoporous volume and particularly the unique hierarchical core/shell nanostructure along with 3D large interconnected interstitial volume guarantee fast mass transport in hollow macroporous core/mesoporous shell carbon (HCMSC), and enable HCMSC to have highly enhanced catalytic activity toward the reduction of I(3)(-), and accordingly considerably improved photovoltaic performance. HCMSC exhibits a V(oc) of 0.74 V, which is 20 mV higher than that (i.e., 0.72 V) of Pt. In addition, it also demonstrates a fill factor of 0.67 and an energy conversion efficiency of 7.56%, which are markedly higher than those of its carbon counterparts and comparable to that of Pt (i.e., fill factor of 0.70 and conversion efficiency of 7.79%). Furthermore, HCMSC possesses excellent chemical stability in the liquid electrolyte containing I(-)/I(3)(-) redox couples, namely, after 60 days of aging, ca. 87% of its initial efficiency is still achieved by the solar cell based on HCMSC counter electrode. PMID:20334406

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

    PubMed

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

    2014-06-21

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

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

    SciTech Connect

    Parkinson, Bruce

    2010-06-04

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

  2. Novel metal-organic photocatalysts: synthesis, characterization and decomposition of organic dyes.

    PubMed

    Gopal Reddy, N B; Murali Krishna, P; Kottam, Nagaraju

    2015-02-25

    An efficient method for the photocatalytic degradation of methylene blue in an aqueous medium was developed using metal-organic complexes. Two novel complexes were synthesized using, Schiff base ligand, N'-[(E)-(4-ethylphenyl)methylidene]-4-hydroxybenzohydrazide (HL) and Ni(II) (Complex 1)/Co(II) (Complex 2) chloride respectively. These complexes were characterized using microanalysis, various spectral techniques. Spectral studies reveal that the complexes exhibit square planar geometry with ligand coordination through azomethine nitrogen and enolic oxygen. The effects of catalyst dosage, irradiation time and aqueous pH on the photocatalytic activity were studied systematically. The photocatalytic activity was found to be more efficient in the presence of Ni(II) complexes than the Co(II) complex. Possible mechanistic aspects were discussed. PMID:25233028

  3. A highly selective optode for determination of Hg (II) by a modified immobilization of indigo carmine on a triacetylcellulose membrane

    NASA Astrophysics Data System (ADS)

    Tavallali, Hossein; Shaabanpur, Elham; Vahdati, Parvin

    2012-04-01

    A new mercury optical sensor was designed with indigo carmine (IC) as a dye indicator. The water-soluble indicator was lipophilized in the form of an ion-pair with N-cetyl pyridinium chloride (CPC) and dissolved in methanol (70 °C), then immobilized on a triacetylcellulose membrane. This optode exhibits a linear range of 24.0-468.0 ?M of the Hg (II) ion concentration with detection limit of 7.2 ?M at 669.5 nm. Response time was within 8-10 min, depending on the Hg (II) ion concentration. The sensor could readily be regenerated with a hydrochloric acid solution (0.01 M) in a reversible manner and its response was reproducible (RSD = 3.2%). The method was applied to the determination of mercury content of a variety of samples which gave satisfactory results.

  4. 2,3-Dipentyldithieno[3,2-f:2',3'-h]quinoxaline-Based Organic Dyes for Efficient Dye-Sensitized Solar Cells: Effect of ?-Bridges and Electron Donors on Solar Cell Performance.

    PubMed

    Huang, Zu-Sheng; Zang, Xu-Feng; Hua, Tao; Wang, Lingyun; Meier, Herbert; Cao, Derong

    2015-09-16

    Five novel metal-free organic dyes DQ1-5 containing a dipentyldithieno[3,2-f:2',3'-h]quinoxaline (DPQ) unit were synthesized and applied in dye-sensitized solar cells (DSSCs), where DPQ was employed as a ?-spacer for the first time. Their photophysical, electrochemical, and theoretical calculations and photovoltaic properties were systematically investigated. All the five dyes show broad photoresponse. Especially the absorption edges of DQ3-5 extend to 800 nm on the TiO2 films. The inserted electron-rich unit 3,4-ethylenedioxythiophene or electron-withdrawing group benzothiadiazole (BTD) in DPQ-based dyes can greatly influence the optoelectronic properties of the dyes. In addition, the different electron donors also significantly affect the performance of the DSSCs. Under standard global AM 1.5 solar light conditions, the DQ5 sensitized solar cell obtained a power conversion efficiency of 7.12%. The result indicates that the rigid DPQ-based organic dye is a promising candidate for efficient DSSCs. PMID:26327692

  5. Removal of malachite green dye from wastewater by different organic acid-modified natural adsorbent: kinetics, equilibriums, mechanisms, practical application, and disposal of dye-loaded adsorbent.

    PubMed

    Wang, Hou; Yuan, Xingzhong; Zeng, Guangming; Leng, Lijian; Peng, Xin; Liao, Kailingli; Peng, Lijuan; Xiao, Zhihua

    2014-10-01

    Natural adsorbent (Cinnamomum camphora sawdust) modified by organic acid (oxalic acid, citric acid, and tartaric acid) was investigated as a potential adsorbent for the removal of hazardous malachite green (MG) dye in aqueous media in a batch process. The extent of MG adsorption onto modified sawdust increased with increasing organic acid concentrations, pH, contact time, and temperature but decreased with increasing adsorbent dosage and ionic strength. Kinetic study indicated that the pseudo-second-order kinetic model could best describe the adsorption kinetics of MG. Equilibrium data were found to fit well with the Langmuir model, and the maximum adsorption capacity of the three kinds of organic acid-modified sawdust was 280.3, 222.8, and 157.5 mg/g, respectively. Thermodynamic parameters suggested that the sorption of MG was an endothermic process. The adsorption mechanism, the application of adsorbents in practical wastewater, the prediction of single-stage batch adsorption system, and the disposal of depleted adsorbents were also discussed. PMID:25028314

  6. Photostabilizing effects of lidocaine and tris(8-hydroxy-quinoline) aluminum on organic fluorescent dyes

    NASA Astrophysics Data System (ADS)

    Sisk, Wade N.

    2003-07-01

    The photostabilization efficacy of lidocaine and tris(8-hydroxy-quinoline) aluminum (Alq3) was determined for methanol solutions of the fluorescent laser dyes 1,3,5,7,8-pentamethyl-2,6-diethylpyrromethene-difluoroborate complex (PM-567) and rhodamine 590 (R590) by evaluation with the , rose bengal (RB). The photostability was measured by noting the decrease in fluorescence with accumulated 532 nm Nd:YAG laser pulses. Rose bengal demonstrated dramatic photostability enhancement upon lidocaine or Alq3 addition; whereas nominal photostability enhancement was observed for PM-567 and R590 upon lidocaine or Alq3 addition. A geminate dye-singlet oxygen complex is proposed to explain the disparity in dye photostability enhancement between rose bengal and the laser dyes.

  7. Induction, Purification and Characterization of a Novel Manganese Peroxidase from Irpex lacteus CD2 and Its Application in the Decolorization of Different Types of Dye

    PubMed Central

    Qin, Xing; Zhang, Jie; Zhang, Xiaoyu; Yang, Yang

    2014-01-01

    Manganese peroxidase (MnP) is the one of the important ligninolytic enzymes produced by lignin-degrading fungi which has the great application value in the field of environmental biotechnology. Searching for new MnP with stronger tolerance to metal ions and organic solvents is important for the maximization of potential of MnP in the biodegradation of recalcitrant xenobiotics. In this study, it was found that oxalic acid, veratryl alcohol and 2,6-Dimehoxyphenol could stimulate the synthesis of MnP in the white-rot fungus Irpex lacteus CD2. A novel manganese peroxidase named as CD2-MnP was purified and characterized from this fungus. CD2-MnP had a strong capability for tolerating different metal ions such as Ca2+, Cd2+, Co2+, Mg2+, Ni2+ and Zn2+ as well as organic solvents such as methanol, ethanol, DMSO, ethylene glycol, isopropyl alcohol, butanediol and glycerin. The different types of dyes including the azo dye (Remazol Brilliant Violet 5R, Direct Red 5B), anthraquinone dye (Remazol Brilliant Blue R), indigo dye (Indigo Carmine) and triphenylmethane dye (Methyl Green) as well as simulated textile wastewater could be efficiently decolorized by CD2-MnP. CD2-MnP also had a strong ability of decolorizing different dyes with the coexistence of metal ions and organic solvents. In summary, CD2-MnP from Irpex lacteus CD2 could effectively degrade a broad range of synthetic dyes and exhibit a great potential for environmental biotechnology. PMID:25412169

  8. Ultralow detection limits for an organic dye determined by fluorescence spectroscopy with laser diode excitation

    SciTech Connect

    Johnson, P.A.; Barber, T.E.; Smith, B.W.; Winefordner, J.D. )

    1989-04-15

    Fluorescence of IR-140, a laser dye in methanol solution, is excited by a semiconductor laser diode. Analytical figures of merit are compared for three different instrumental configurations, with the dye measured in a cuvette, a liquid jet, and a compact instrument. The best limit of detection, 46,000 molecules, was achieved with a liquid jet. Linear dynamic range was 6 orders of magnitude. The laser diode operates in the near-infrared region, resulting in low background fluorescence.

  9. The mitochondrial fluorescent dye rhodamine 123 is a high-affinity substrate for organic cation transporters (OCTs) 1 and 2.

    PubMed

    Jouan, Elodie; Le Vee, Marc; Denizot, Claire; Da Violante, Georges; Fardel, Olivier

    2014-02-01

    Rhodamine 123 is a fluorescent cationic dye commonly used as a mitochondrial probe and known or suspected to be transported by certain drug membrane transporters. The present study was designed to characterize the putative interactions of rhodamine 123 with human organic cation transporter (OCT) 1 and OCT2. Intracellular uptake of the dye was demonstrated to be enhanced in both hOCT1- and hOCT2-overexpressing HEK293 cells when compared with control HEK293 cells. This increase of rhodamine 123 influxes was found to be a saturable carrier-mediated process, with low K(m) values (K(m) = 0.54 ?m and K(m) = 0.61 ?m for transport of the dye in hOCT1- and hOCT2-positive HEK293 cells, respectively). Known inhibitors of hOCT1 and hOCT2 activities such as verapamil, amitriptyline, prazosin, and quinine were next demonstrated to decrease rhodamine 123 accumulation in hOCT1- and hOCT2-overexpressing HEK293 cells. In addition, the dye was found to inhibit hOCT1- and hOCT2-mediated uptake of tetraethylammonium (TEA), a model substrate for both hOCT1 and hOCT2; rhodamine 123 appeared nevertheless to be a more potent inhibitor of hOCT1-mediated TEA transport (IC?? = 0.37 ?m) than of that mediated by hOCT2 (IC?? = 61.5 ?m). Taken together, these data demonstrate that rhodamine 123 is a high-affinity substrate for both hOCT1 and hOCT2. This dye may be therefore useful for fluorimetrically investigating cellular hOCT1 or hOCT2 activity, knowing, however, that other factors potentially contributing to cellular accumulation of rhodamine 123, including mitochondrial membrane potential or expression of the efflux transporter P-glycoprotein, have also to be considered. PMID:22913740

  10. Activated carbon doped with biogenic manganese oxides for the removal of indigo carmine.

    PubMed

    Hu, Yichen; Chen, Xiao; Liu, Zhiqiang; Wang, Gejiao; Liao, Shuijiao

    2016-01-15

    Indigo carmine (IC) is one of the oldest, most important, and highly toxic dyes which is released from the effluents of many industries and results in serious pollution in water. In this study, the biogenic Mn oxides were activated by NaOH and then heated for 3 h at 350 °C to produce activated carbon doped with Mn oxide (Bio-MnOx-C), which were produced by culturing Mn (II)-oxidizing bacterial strain MnI7-9 in liquid A medium at 28 °C with 10 mmol/L MnCl2. Bio-MnOx-C was characterized by SEM, TEM, IR, XPS, XRD, etc. It contained C, O, and Mn which comprised Mn (IV) and Mn (III) valence states at a ratio of 3.81:1. It had poorly crystalline ?-MnO2 with a specific surface area of 130.94 m(2)/g. A total of 0.1 g Bio-MnOx-C could remove 45.95 g IC from 500 mg/L IC solution after 0.5 h contact time. IC removal by Bio-MnOx-C included a rapid oxidation reaction and the removal reaction followed second-order kinetic equation. These results confirmed that Bio-MnOx-C could be a potential material for wastewater remediation. PMID:26595178

  11. Analysis of interaction between the organic dye methylene blue and the surface of AgCl(I) microcrystals

    NASA Astrophysics Data System (ADS)

    Ovchinnikov, O. V.; Chernykh, S. V.; Smirnov, M. S.; Alpatova, D. V.; Vorob'eva, R. P.; Latyshev, A. N.; Evlev, A. B.; Utekhin, A. N.; Lukin, A. N.

    2007-11-01

    We have used IR spectroscopy to study the nature of interaction between molecules of the organic dye methylene blue (MB) and the surface of AgCl(I) microcrystals. We recorded the IR absorption spectra of the organic dye methylene blue in the gas phase, adsorbed on the surface of AgCl(I) microcrystals, and also in the form of crystal hydrates. The results obtained allowed us to hypothesize that unsaturated dimethylamino groups and the sulfur atom in the heterocycle of this dye are the most active in the interaction between methylene blue molecules and the surface of AgCl(I) microcrystals. With the help of IR spectra of methylene blue crystal hydrates, we confirmed the significant role of OH groups during adsorption of molecules on the surface of AgCl(I) microcrystals. We suggest the possibility of formation of hydrogen bonds between the anions of the crystal lattice and the unsaturated dimethylamino groups as well as the sulfur atoms in the heterocycle, by formation of hydrogen bonds with the OH groups.

  12. Microscopy of hierarchically organized TiO2 photoelectrode for dye solar cells

    NASA Astrophysics Data System (ADS)

    Eskandar, A.; Mohamed, N. M.

    2015-07-01

    Research on improving the performance of dye solar cells has various aspects of the device being investigated. This paper analyzes the deliberately hierarchized photoelectrode configuration for DSC applications to improve the performance of DSCs. Multiple layers of differently composed TiO2 particle types namely aggregates and nanoparticles were deposited to form a photoelectrode with thickness of about 12 µm. The photoelectrodes were assembled into working DSCs with an active area of 1 cm2. Measurement for solar power conversion performance was measured under 1 sun at AM1.5 spectrum simulated sunlight. Electron microscopy for photoelectrode analysis was conducted using Field Emission Scattering Electron Microscopy with enhanced resolution. External Quantum Efficiency was measured using a purpose built instrument. Kinetics were investigated using the Electrochemical Impedance Spectroscopy (EIS) measurement with a potentiostat. The best performing DSC is of the hierarchically organized photoelectrode with a photoconversion efficiency of 4.58%, an increase of 14% in comparison to the reference samples with fully aggregates configuration. Short circuit current density, Jsc increases by about 2.223 mA cm-2 relative to the blanks. The electron microscopy confirmed expected thickness at around 10 µm and layers forming the photoelectrode being hierarchically deposited with ˜20 nm TiO2 nanoparticles and 450 nm TiO2 aggregates mixture composition. EQE improved especially for visible region of 500-550 nm light wavelengths with 12 % increase in the response of in that region. Improvement to the diffusion coefficient as measured by the EIS contributed to the performance increase of the photoelectrode configuration under investigation.

  13. Screening for larvicidal activity of ten carminative plants.

    PubMed

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

    1998-09-01

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

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

    PubMed Central

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

    2014-01-01

    Summary The combination of a dye which absorbs the photon, an electron acceptor and an electron donor leading to energy conversion through electron transfer, was the basis of the so called three-component systems. In this paper, an experimental work combining Rose bengal dye with a triazine derivative as electron acceptor and ethyl 4-(dimethylamino)benzoate as electron donor, will underline the benefit of the photocyclic behavior of three-component systems leading to the dye regeneration. A thermodynamic approach of the photocycle is presented, followed by a mechanistic and computational study of ideal photocycles, in order to outline the specific kinetics occuring in so called photocatalytic systems. The simple kinetic model used is enough to outline the benefit of the cyclic system and to give the basic requirements in term of chemical combination needed to be fulfilled in order to obtain a photocatalytic behavior. PMID:24991243

  15. Thermoresponsive cellulose ether and its flocculation behavior for organic dye removal.

    PubMed

    Tian, Ye; Ju, Benzhi; Zhang, Shufen; Hou, Linan

    2016-01-20

    A thermoresponsive polymer, 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC), was prepared by grafting butyl glycidyl ether (BGE) onto hydroxyethyl cellulose (HEC). The lower critical solution temperature (LCST) and critical flocculation temperature (CFT) of HBPEC were varied by changing the molar substitution (MS) and salt concentrations. Transmission electron microscopy (TEM) images and fluorescence spectroscopy showed that HBPEC can assemble into micelles. Additionally, using Nile Red as a model dye, the performance of HBPEC for the removing Nile Red from aqueous solutions via cloud point extraction procedures was investigated in detail. The encapsulation behavior of dye in the aqueous solution of HBPEC was studied by fluorescence spectroscopy and fluorescence microscope. The experimental results indicated that 99.4% of dye was removed from the aqueous solutions, and the HBPEC was recycled and reused easily, Furthermore, the recycle efficiency (RE) and maximum loading capacity portrayed little loss with the number of cycles. PMID:26572464

  16. Preparation of cube micrometer potassium niobate (KNbO3) by hydrothermal method and sonocatalytic degradation of organic dye.

    PubMed

    Zhang, Hongbo; Wei, Chunsheng; Huang, Yingying; Wang, Jun

    2016-05-01

    Cube micrometer potassium niobate (KNbO3) powder, as a high effective sonocatalyst, was prepared using hydrothermal method, and then, was characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). In order to evaluate the sonocatalytic activity of prepared KNbO3 powder, the sonocatalytic degradation of some organic dyes was studied. In addition, some influencing factors such as heat-treatment temperature and heat-treatment time on the sonocatalytic activity of prepared KNbO3 powder and catalyst added amount and ultrasonic irradiation time on the sonocatalytic degradation efficiency were examined by using UV-visible spectrophotometer and Total Organic Carbon (TOC) determination. The experimental results showed that the best sonocatalytic degradation ratio (69.23%) of organic dyes could be obtained when the conditions of 5.00mg/L initial concentration, 1.00g/L prepared KNbO3 powder (heat-treated at 400°C for 60min) added amount, 5.00h ultrasonic irradiation (40kHz frequency and 300W output power), 100mL total volume and 25-28°C temperature were adopted. Therefore, the micrometer KNbO3 powder could be considered as an effective sonocatalyst for treating non- or low-transparent organic wastewaters. PMID:26597541

  17. Doping effects of fluorinated organic dyes on the open-circuit voltage of bulk-heterojunction photovoltaic devices

    NASA Astrophysics Data System (ADS)

    Watanabe, Tomoki; Yamashita, Kenichi

    2015-08-01

    We have investigated photovoltaic properties of bulk-heterojunction (BHJ) organic absorption layer doped with fluorinated Coumarin dyes. By dilute doping of a fluorinated Coumarin dye, Coumarin 307, into poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) BHJ absorption layer, the open-circuit voltage of photovoltaic device increased by ?90 mV without the significant degradation in the short-circuit current density. On the other hand, the doping of non-fluorinated Coumarin dye such as Coumarin 2 did not induce such the enhancement effect in the open-circuit voltage. In ultraviolet photoelectron spectroscopies, the doping of Coumarin 307 was found to have no impact on P3HT, but the density of state of PCBM was significantly modified by the doping. The change in the density of state was confirmed also in ultraviolet absorption measurement. Possible explanations for the enhancement in the open-circuit voltage are discussed from the experimental results, and a shift of the vacuum level by the doping can be considered as a direct origin.

  18. Response Characterization of a Fiber Optic Sensor Array with Dye-Coated Planar Waveguide for Detection of Volatile Organic Compounds

    PubMed Central

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

    2014-01-01

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

  19. Rational Molecular Engineering of Indoline-Based D-A-?-A Organic Sensitizers for Long-Wavelength-Responsive Dye-Sensitized Solar Cells.

    PubMed

    Zhang, Weiwei; Wu, Yongzhen; Zhu, Haibo; Chai, Qipeng; Liu, Jingchuan; Li, Hui; Song, Xiongrong; Zhu, Wei-Hong

    2015-12-01

    Indoline-based D-A-?-A organic sensitizers are promising candidates for highly efficient and long-term stable dye-sensitized solar cells (DSSCs). In order to further broaden the spectral response of the known indoline dye WS-2, we rationally engineer the molecular structure through enhancing the electron donor and extending the ?-bridge, resulting in two novel indoline-based D-A-?-A organic sensitizers WS-92 and WS-95. By replacing the 4-methylphenyl group on the indoline donor of WS-2 with a more electron-rich carbazole unit, the intramolecular charge transfer (ICT) absorption band of dye WS-92 is slightly red-shifted from 550 nm (WS-2) to 554 nm (WS-92). In comparison, the incorporation of a larger ?-bridge of cyclopentadithiophene (CPDT) unit in dye WS-95 not only greatly bathochromatically tunes the absorption band to 574 nm but also largely enhances the molar extinction coefficients (?), thus dramatically improving the light-harvesting capability. Under the standard global AM 1.5 solar light condition, the photovoltaic performances of both organic dyes have been evaluated in DSSCs on the basis of the iodide/triiodide electrolyte without any coadsorbent or cosensitizer. The DSSCs based on WS-95 display better device performance with power conversion efficiency (?) of 7.69%. The additional coadsorbent in the dye bath of WS-95 does not improve the photovoltaic performance, indicative of its negligible dye aggregation, which can be rationalized by the grafted dioctyl chains on the CPDT unit. The cosensitization of WS-95 with a short absorption wavelength dye S2 enhances the IPCE and improves the ? to 9.18%. Our results indicate that extending the ?-spacer is more rational than enhancing the electron donor in terms of broadening the spectral response of indoline-based D-A-?-A organic sensitizers. PMID:26552499

  20. Synthesis of fungus-like MoS2 nanosheets with ultrafast adsorption capacities toward organic dyes

    NASA Astrophysics Data System (ADS)

    Song, HaoJie; You, Shengsheng; Jia, XiaoHua

    2015-11-01

    Fungus-like molybdenum disulfide (MoS2) nanosheets with a thickness of a few nanometers have been successfully synthesized via one-pot hydrothermal method. The as-prepared MoS2 nanosheets with a high surface area of 106.989 m2 g-1 exhibited excellent wastewater treatment performance with high removal capacities toward organic dyes. In addition, the fungus-like MoS2 nanosheets can absorb Congo red completely within 2 min. Successful access to high quality fungus-like MoS2 nanosheets will make it possible for their potential application in catalysis and other fields.

  1. Organic dyes incorporating the dithieno[3',2':3,4;2?,3?:5,6]benzo[1,2-c]furazan moiety for dye-sensitized solar cells.

    PubMed

    Ni, Jen-Shyang; You, Jian-Hao; Hung, Wei-I; Kao, Wei-Siang; Chou, Hsien-Hsin; Lin, Jiann T

    2014-12-24

    New D-?-A'-?-A type sensitizers (JH dyes), comprised arylamine as the electron donor, dithieno[3',2':3,4;2?,3?:5,6]benzo[1,2-c]furazan (DTBF) in the conjugated spacer, and 2-cyanoacrylic acid as both the acceptor and anchor, have been synthesized. The JH dyes have broad absorption spectra covering the range of 350 to 600 nm with the highest molar extinction coefficient up to >40?000 M(-1) cm(-1). The dye-sensitized solar cells (DSSCs) fabricated from the dyes exhibited light-to-electricity conversions ranging from 1.42 to 6.18% under simulated AM 1.5 G illumination. Upon adding 10 mM CDCA as the coadsorbent, the best performance cell has the power conversion efficiency of 7.33%, which is close to that of N719-based standard DSSC (7.56%). PMID:25470385

  2. Organic Dyes Incorporating the Dithieno[3,2-f:2',3'-h]quinoxaline Moiety for Dye-Sensitized Solar Cells.

    PubMed

    Ni, Jen-Shyang; Kao, Wei-Siang; Chou, Hao-Ju; Lin, Jiann T

    2015-09-01

    New donor-acceptor'-acceptor-type sensitizers (QBT dyes), comprising arylamine as the electron donor, dithieno[3,2-f:2',3'-h]quinoxaline as the internal acceptor, and 2-cyanoacrylic acid as both the acceptor and anchor, have been synthesized. The QBT dyes have broad absorption spectra covering the range of ?=368-487?nm with a highest molar extinction coefficient of up to approximately 40?000?M(-1) ?cm(-1) . The light-to-electricity conversion efficiencies of the dye-sensitized solar cells (DSSCs) fabricated from the dyes range from 6.11 to 7.59?% under simulated AM?1.5?G illumination. Upon addition of a threefold concentration of chenodeoxycholic acid as the co-adsorbent, the best performance cell has a power-conversion efficiency of 8.41?%, which is higher than that of the N719-based standard DSSC (8.27?%). PMID:25853981

  3. Experimental and numerical investigation of the effect of liquid temperature on the sonolytic degradation of some organic dyes in water.

    PubMed

    Merouani, Slimane; Hamdaoui, Oualid; Boutamine, Zineb; Rezgui, Yacine; Guemini, Miloud

    2016-01-01

    This paper presents a comprehensive experimental and numerical investigation of the effects of liquid temperature on the sonochemical degradation of three organic dyes, Rhodamine B (RhB), Acid orange 7 (AO7) and Malachite green (MG), largely used in the textile industry. The experiments have been carried out for an ultrasonic frequency of 300 kHz. The obtained experimental results were discussed using a new approach combining the results of single-bubble event and the number of active bubbles. The single-bubble event was predicted using a model that combines the bubble dynamics with chemical kinetics occurring inside a bubble during the strong collapse. The number of active bubbles was predicted using a method developed in our previous work. The experiments showed that the degradation rate of the three dyes increased significantly with increasing liquid temperature in the range 25-55°C. It was predicted that the main pathway of pollutants degradation is the attack by OH radicals. The simulations showed that there exists an optimum liquid temperature of about 35°C for the production of OH inside a bubble whereas the number of active bubbles increased sharply with the rise of the liquid temperature. It was predicted that the overall production rate of OH increased with increasing liquid temperature in the range 25-55°C. Finally, it was concluded that the effect of liquid temperature on the sonochemical degradation of the three dyes in aqueous phase was controlled by the number of active bubbles in the range 35-55°C and by both the number of bubbles and the single bubble yield in the range 25-35°C. PMID:26384922

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

    NASA Astrophysics Data System (ADS)

    Miloševi?, Maja; Logar, Mihovil

    2014-05-01

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

  5. UV light induced photodegradation of organic dye by ZnO nanocatalysts

    SciTech Connect

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

    2013-06-03

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

  6. Hybrid functional calculated optical and electronic structures of thin anatase TiO2 nanowires with organic dye adsorbates

    NASA Astrophysics Data System (ADS)

    Ünal, Hatice; Gunceler, Deniz; Gülseren, O?uz; Ellialt?o?lu, ?inasi; Mete, Ersen

    2015-11-01

    The electronic and optical properties of thin anatase TiO2 (1 0 1) and (0 0 1) nanowires have been investigated using the screened Coulomb hybrid density functional calculations. For the bare nanowires with sub-nanometer diameters, the calculated band gaps are larger relative to the bulk values due to size effects. The role of organic light harvesting sensitizers on the absorption characteristics of the anatase nanowires has been examined using the hybrid density functional method incorporating partial exact exchange with range separation. For the lowest lying excitations, directional charge redistribution of tetrahydroquinoline (C2-1) dye shows a remarkably different profile in comparison to a simple molecule which is chosen as the coumarin skeleton. The binding modes and the adsorption energies of C2-1 dye and coumarin core on the anatase nanowires have been studied including non-linear solvation effetcs. The calculated optical and electronic properties of the nanowires with these two different types of sensitizers have been interpreted in terms of their electron-hole generation, charge carrier injection and recombination characteristics.

  7. Facile and Scalable Preparation of Graphene Oxide-Based Magnetic Hybrids for Fast and Highly Efficient Removal of Organic Dyes

    NASA Astrophysics Data System (ADS)

    Jiao, Tifeng; Liu, Yazhou; Wu, Yitian; Zhang, Qingrui; Yan, Xuehai; Gao, Faming; Bauer, Adam J. P.; Liu, Jianzhao; Zeng, Tingying; Li, Bingbing

    2015-07-01

    This study reports the facile preparation and the dye removal efficiency of nanohybrids composed of graphene oxide (GO) and Fe3O4 nanoparticles with various geometrical structures. In comparison to previously reported GO/Fe3O4 composites prepared through the one-pot, in situ deposition of Fe3O4 nanoparticles, the GO/Fe3O4 nanohybrids reported here were obtained by taking advantage of the physical affinities between sulfonated GO and Fe3O4 nanoparticles, which allows tuning the dimensions and geometries of Fe3O4 nanoparticles in order to decrease their contact area with GO, while still maintaining the magnetic properties of the nanohybrids for easy separation and adsorbent recycling. Both the as-prepared and regenerated nanohybrids demonstrate a nearly 100% removal rate for methylene blue and an impressively high removal rate for Rhodamine B. This study provides new insights into the facile and controllable industrial scale fabrication of safe and highly efficient GO-based adsorbents for dye or other organic pollutants in a wide range of environmental-related applications.

  8. Tunable synthesis of SiO2-encapsulated zero-valent iron nanoparticles for degradation of organic dyes.

    PubMed

    Mao, Zhou; Wu, Qingzhi; Wang, Min; Yang, Yushi; Long, Jia; Chen, Xiaohui

    2014-01-01

    A series of nanocomposites consisting of zero-valent iron nanoparticles (ZVI NPs) encapsulated in SiO2 microspheres were successfully synthesized through a successive two-step method, i.e., the wet chemical reduction by borohydride followed by a modified Stöber method. The as-synthesized nanocomposites were characterized using X-ray diffraction, field emission scanning electron microscopy, vibrating sample magnetometer, and inductively coupled plasma-atomic emission spectrometer. The catalytic performance of SiO2-encapsulated ZVI nanocomposites for the degradation of organic dyes was investigated using methylene blue (MB) as the model dye in the presence of H2O2. The results showed that the degradation efficiency and apparent rate constant of the degradation reaction were significantly enhanced with increased ZVI NPs encapsulated in SiO2 microspheres, whereas the dosage of H2O2 remarkably promoted degradation rate without affecting degradation efficiency. The content-dependent magnetic property ensured the excellent magnetic separation of degradation products under an external magnet. This strategy for the synthesis of SiO2-encapsulated ZVI NPs nanocomposites was low cost and easy to scale-up for industrial production, thereby enabling promising applications in environmental remediation. PMID:25258615

  9. Facile and Scalable Preparation of Graphene Oxide-Based Magnetic Hybrids for Fast and Highly Efficient Removal of Organic Dyes

    PubMed Central

    Jiao, Tifeng; Liu, Yazhou; Wu, Yitian; Zhang, Qingrui; Yan, Xuehai; Gao, Faming; Bauer, Adam J. P.; Liu, Jianzhao; Zeng, Tingying; Li, Bingbing

    2015-01-01

    This study reports the facile preparation and the dye removal efficiency of nanohybrids composed of graphene oxide (GO) and Fe3O4 nanoparticles with various geometrical structures. In comparison to previously reported GO/Fe3O4 composites prepared through the one-pot, in situ deposition of Fe3O4 nanoparticles, the GO/Fe3O4 nanohybrids reported here were obtained by taking advantage of the physical affinities between sulfonated GO and Fe3O4 nanoparticles, which allows tuning the dimensions and geometries of Fe3O4 nanoparticles in order to decrease their contact area with GO, while still maintaining the magnetic properties of the nanohybrids for easy separation and adsorbent recycling. Both the as-prepared and regenerated nanohybrids demonstrate a nearly 100% removal rate for methylene blue and an impressively high removal rate for Rhodamine B. This study provides new insights into the facile and controllable industrial scale fabrication of safe and highly efficient GO-based adsorbents for dye or other organic pollutants in a wide range of environmental-related applications. PMID:26220847

  10. Tunable synthesis of SiO2-encapsulated zero-valent iron nanoparticles for degradation of organic dyes

    PubMed Central

    2014-01-01

    A series of nanocomposites consisting of zero-valent iron nanoparticles (ZVI NPs) encapsulated in SiO2 microspheres were successfully synthesized through a successive two-step method, i.e., the wet chemical reduction by borohydride followed by a modified Stöber method. The as-synthesized nanocomposites were characterized using X-ray diffraction, field emission scanning electron microscopy, vibrating sample magnetometer, and inductively coupled plasma-atomic emission spectrometer. The catalytic performance of SiO2-encapsulated ZVI nanocomposites for the degradation of organic dyes was investigated using methylene blue (MB) as the model dye in the presence of H2O2. The results showed that the degradation efficiency and apparent rate constant of the degradation reaction were significantly enhanced with increased ZVI NPs encapsulated in SiO2 microspheres, whereas the dosage of H2O2 remarkably promoted degradation rate without affecting degradation efficiency. The content-dependent magnetic property ensured the excellent magnetic separation of degradation products under an external magnet. This strategy for the synthesis of SiO2-encapsulated ZVI NPs nanocomposites was low cost and easy to scale-up for industrial production, thereby enabling promising applications in environmental remediation. PMID:25258615

  11. The energy transfer mechanism of a photoexcited and electroluminescent organic hybrid thin film of blue, green, and red laser dyes

    NASA Astrophysics Data System (ADS)

    Li, Weiling; Zhang, Jing; Zheng, Yanqiong; Chen, Guo; Cai, Miao; Wei, Bin

    2015-04-01

    Though optically pumped lasing has been realized for years, electrically pumped lasing has not yet been achieved in organic semiconductor devices. In order to make a better understanding of the laser mechanisms of the organic materials, we prepared organic thin films consisting of three efficient laser dyes of a blue emitter, 4?,4?'-N,N-diphenylamine-4,4'-diphenyl-1,1'-binaphthyl (BN), a green emitter, 1,4-bis[2-[4-[N,N-di(p-tolyl)amino] phenyl]vinyl]benzene (DSB), and a red emitter, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidy-l-9-enyl)-4H-pyran (DCJTB) with different doping concentrations for the first time to investigate the cascade energy transfer process. The energy transfer schemes in the co-doped thin films in photoluminescence and electroluminescence have been investigated. The results indicated that the DSB molecules acted as a bridge to deliver energy more effectively from the host (BN) to the guest (DCJTB). Meanwhile, the maximum current efficiency ( C E) and power efficiency ( P E) of the organic light-emitting devices (OLEDs) with the emitting layer of lower doping concentration were 13.5 cd/A and 14.1 lm/W, respectively.

  12. Palladium complexes of perylene diimides: strong fluorescence despite direct attachment of late transition metals to organic dyes.

    PubMed

    Weissman, Haim; Shirman, Elijah; Ben-Moshe, Tal; Cohen, Revital; Leitus, Gregory; Shimon, Linda J W; Rybtchinski, Boris

    2007-06-11

    We prepared the first sigma-bonded metal complexes of widely utilized organic dyes, perylene tetracarboxylic acid diimides (PDIs). These 1,7-dipalladium PDI complexes were synthesized by C-Br oxidative addition of 1,7-dibromo-N,N'-dicyclohexyl PDI (Br2PDI) to Pd(0) phosphine complexes bearing triphenylphosphine and bischelating 1,2-bis(diphenylphosphino)ethane (dppe). The structures of Pd-PDI complexes were elucidated by single-crystal X-ray analysis. Surprisingly, despite direct attachement of two late transition metal centers, Pd-PDI systems are highly fluorescent (Phi=0.65 and 0.22 for triphenylphosphine and dppe systems, respectively). This is rationalized in terms of weak electronic interactions between the metal centers and PDI pi-system, as revealed by TD-DFT calculations. PMID:17503813

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

    SciTech Connect

    Avdeeva, V I; Shapiro, Boris I; Kuch'yanov, Aleksandr S; Plekhanov, A I; Solominskii, Yu L; Tolmachev, Alexei I

    2003-06-30

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

  14. Amphiphilic block-graft copolymer templates for organized mesoporous TiO2 films in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lim, Jung Yup; Lee, Chang Soo; Lee, Jung Min; Ahn, Joonmo; Cho, Hyung Hee; Kim, Jong Hak

    2016-01-01

    Amphiphilic block-graft copolymers composed of poly(styrene-b-butadiene-b-styrene) (SBS) backbone and poly(oxyethylene methacrylate) (POEM) side chains are synthesized and combined with hydrophilically preformed TiO2 (Pre-TiO2), which works as a structural binder as well as titania source. This results in the formation of crack free, 6-?m-thick, organized mesoporous TiO2 (OM-TiO2) films via one-step doctor-blading based on self-assembly of SBS-g-POEM as well as preferential interaction of POEM chains with Pre-TiO2. SBS-g-POEM with different numbers of ethylene oxide repeating units, SBS-g-POEM(500) and SBS-g-POEM(950), are used to form OM-TiO2(500) and OM-TiO2(950), respectively. The efficiencies of dye-sensitized solar cells (DSSCs) with a quasi-solid-state polymer electrolyte reach 5.7% and 5.8% at 100 mW/cm2 for OM-TiO2(500) and OM-TiO2(950), respectively. The surface area of OM-TiO2(950) was greater than that of OM-TiO2(500) but the light reflectance was lower in the former, which is responsible for similar efficiency. Both DSSCs exhibit much higher efficiency than one (4.8%) with randomly-organized particulate TiO2 (Ran-TiO2), which is attributed to the higher dye loading, reduced charge recombination and improved pore infiltration of OM-TiO2. When utilizing poly((1-(4-ethenylphenyl)methyl)-3-butyl-imidazolium iodide) (PEBII) and mesoporous TiO2 spheres as the solid electrolyte and the scattering layer, the efficiency increases up to 7.5%, one of the highest values for N719-based solid-state DSSCs.

  15. Metal-free organic sensitizers for use in water-splitting dye-sensitized photoelectrochemical cells

    PubMed Central

    Swierk, John R.; Méndez-Hernández, Dalvin D.; McCool, Nicholas S.; Liddell, Paul; Terazono, Yuichi; Pahk, Ian; Tomlin, John J.; Oster, Nolan V.; Moore, Thomas A.; Moore, Ana L.; Gust, Devens; Mallouk, Thomas E.

    2015-01-01

    Solar fuel generation requires the efficient capture and conversion of visible light. In both natural and artificial systems, molecular sensitizers can be tuned to capture, convert, and transfer visible light energy. We demonstrate that a series of metal-free porphyrins can drive photoelectrochemical water splitting under broadband and red light (? > 590 nm) illumination in a dye-sensitized TiO2 solar cell. We report the synthesis, spectral, and electrochemical properties of the sensitizers. Despite slow recombination of photoinjected electrons with oxidized porphyrins, photocurrents are low because of low injection yields and slow electron self-exchange between oxidized porphyrins. The free-base porphyrins are stable under conditions of water photoelectrolysis and in some cases photovoltages in excess of 1 V are observed. PMID:25583488

  16. Aqueous synthesis of hierarchical bismuth nanobundles with high catalytic activity to organic dyes

    NASA Astrophysics Data System (ADS)

    Ma, Dechong; Zhao, Yan; Zhao, Jingzhe; Li, Yawen; Lu, Yan; Zhao, Duijia

    2015-07-01

    Bundle-like bismuth (Bi) nanoarchitectures were successfully prepared on a large scale by an aqueous reducing strategy with polyethylene glycol (PEG) as directing agent at 90 °C for 55 min. The bundle-like Bi nanoarchitectures have a length of 4-5 ?m and diameter of 0.5-1 ?m with fairly uniform construction. Catalytic activities of the as-prepared hierarchical Bi nanobundles were investigated for degrading Rhodamine B (RhB) dye solution under visible-light irradiation. The Bi nanostructures extended excellent catalytic activity and good cycling performance toward photodegradation of RhB. Possible mechanism was proposed for Bi-assisted photocatalytic degradation of RhB under visible-light.

  17. Two-Photon-Absorption Induced Superradiance of a New Organic Dye PSPS

    NASA Astrophysics Data System (ADS)

    Zhou, Guang-Yong; Wang, Dong; Wang, Xiao-Mei; Yang, Sheng-Jun; Xu, Xin-Guang; Zhao, Xian; Shao, Zong-Shu; Jiang, Min-Hua

    2002-05-01

    The linear and nonlinear optical properties of a new two-photon absorption (TPA) dye, trans-4-(4'-pyrrolidinyl styryl)-N-methyl pyridinium methyl sulfate (abbreviated as PSPS) is reported. Intense red superradiance with a peak located at 625nm can be observed from PSPS solution in benzyl alcohol when pumped by a focused picosecond laser beam operated at 1064nm. The lifetimes of one-photon absorption (OPA) and TPA fluorescence were measured to be 370 and 384ps, respectively. The pulse widths of OPA and TPA superradiance were 60 and 58 ps, respectively. The highest net upconversion efficiency from the absorbed pump laser to the upconverted superradiance is 8.3% at the pump energy of 0.6 mJ.

  18. Metal-free organic sensitizers for use in water-splitting dye-sensitized photoelectrochemical cells.

    PubMed

    Swierk, John R; Méndez-Hernández, Dalvin D; McCool, Nicholas S; Liddell, Paul; Terazono, Yuichi; Pahk, Ian; Tomlin, John J; Oster, Nolan V; Moore, Thomas A; Moore, Ana L; Gust, Devens; Mallouk, Thomas E

    2015-02-10

    Solar fuel generation requires the efficient capture and conversion of visible light. In both natural and artificial systems, molecular sensitizers can be tuned to capture, convert, and transfer visible light energy. We demonstrate that a series of metal-free porphyrins can drive photoelectrochemical water splitting under broadband and red light (? > 590 nm) illumination in a dye-sensitized TiO2 solar cell. We report the synthesis, spectral, and electrochemical properties of the sensitizers. Despite slow recombination of photoinjected electrons with oxidized porphyrins, photocurrents are low because of low injection yields and slow electron self-exchange between oxidized porphyrins. The free-base porphyrins are stable under conditions of water photoelectrolysis and in some cases photovoltages in excess of 1 V are observed. PMID:25583488

  19. Photocatalytic degradation of organic dyes by La³?/Ce³?-H?PW??O?? under different light irradiation.

    PubMed

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

    2014-06-28

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

  20. Hydrothermal fabrication of selectively doped organic assisted advanced ZnO nanomaterial for solar driven photocatalysis.

    PubMed

    Namratha, K; Byrappa, K; Byrappa, S; Venkateswarlu, P; Rajasekhar, D; Deepthi, B K

    2015-08-01

    Hydrothermal fabrication of selectively doped (Ag(+)+Pd(3+)) advanced ZnO nanomaterial has been carried out under mild pressure temperature conditions (autogeneous; 150°C). Gluconic acid has been used as a surface modifier to effectively control the particle size and morphology of these ZnO nanoparticles. The experimental parameters were tuned to achieve optimum conditions for the synthesis of selectively doped ZnO nanomaterials with an experimental duration of 4hr. These selectively doped ZnO nanoparticles were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy and scanning electron microscopy (SEM). The solar driven photocatalytic studies have been carried out for organic dyes, i.e., Procion MX-5B dye, Cibacron Brilliant Yellow dye, Indigo Carmine dye, separately and all three mixed, by using gluconic acid modified selectively doped advanced ZnO nanomaterial. The influence of catalyst, its concentration and initial dye concentration resulted in the photocatalytic efficiency of 89% under daylight. PMID:26257367

  1. Catalytic spectrophotometric determination of trace aluminium with indigo carmine

    NASA Astrophysics Data System (ADS)

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

    2007-04-01

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

  2. Relationship between temperature-induced changes in internal microscopic structures of poly(N-isopropylacrylamide) microgels and organic dye uptake behavior.

    PubMed

    Kureha, Takuma; Sato, Takaaki; Suzuki, Daisuke

    2014-07-29

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

  3. Electrochemical DNA sensors based on nanostructured organic dyes/DNA/polyelectrolyte complexes.

    PubMed

    Evtugyn, Gennady A; Stepanova, Veronika B; Porfireva, Anna V; Zamaleeva, Alsu I; Fakhrullin, Rawil R

    2014-09-01

    Polyelectrolyte complexes based on electropolymerized phenothiazine dyes (Methylene Blue and Methylene Green), poly(allylamine hydrochloride), polystyrene sulfonate and native DNA from salmon sperm have been for the first time obtained by self-assembling on the glassy carbon electrode using the layer-by-layer assembly and characterized using direct current voltammetry and electrochemical impedance spectroscopy. The changes in the charge transfer resistance and capacitance are attributed to the charge separation and the regularity of the layers depending on the number of layers and the position of DNA within the complex. Fenton reagent increases the resistance of the outer interface of the modifier with the maximal effect for the coatings including polymeric form of Methylene Green based coatings and direct contact of the DNA and polyphenothiazines. Meanwhile the selectivity of the response was found higher for the coatings based on poly(Methylene Blue). The difference in the behavior of the polyelectrolyte complex including different components makes it possible to distinguish the response related to the DNA damage and changes in the redox status of polyphenothiazines. PMID:25924325

  4. Impact of local compressive stress on the optical transitions of single organic dye molecules

    NASA Astrophysics Data System (ADS)

    Stöttinger, Sven; Hinze, Gerald; Diezemann, Gregor; Oesterling, Ingo; Müllen, Klaus; Basché, Thomas

    2014-03-01

    The ability to mechanically control the optical properties of individual molecules is a grand challenge in nanoscience and could enable the manipulation of chemical reactivity at the single-molecule level. In the past, light has been used to alter the emission wavelength of individual molecules or modulate the energy transfer quantum yield between them. Furthermore, tensile stress has been applied to study the force dependence of protein folding/unfolding and of the chemistry and photochemistry of single molecules, although in these mechanical experiments the strength of the weakest bond limits the amount of applicable force. Here, we show that compressive stress modifies the photophysical properties of individual dye molecules. We use an atomic force microscope tip to prod individual molecules adsorbed on a surface and follow the effect of the applied force on the electronic states of the molecule by fluorescence spectroscopy. Applying a localized compressive force on an isolated molecule induces a stress that is redistributed throughout the structure. Accordingly, we observe reversible spectral shifts and even shifts that persist after retracting the microscope tip, which we attribute to transitions to metastable states. Using quantum-mechanical calculations, we show that these photophysical changes can be associated with transitions among the different possible conformers of the adsorbed molecule.

  5. 75 FR 81949 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ... Notice No. 111 published in the Federal Register (75 FR 67669) on Wednesday, November 3, 2010, TTB... Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages; Comment Period... Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages, a notice of...

  6. Transparent Organic Photodetector using a Near-Infrared Absorbing Cyanine Dye

    PubMed Central

    Zhang, Hui; Jenatsch, Sandra; De Jonghe, Jelissa; Nüesch, Frank; Steim, Roland; Véron, Anna C.; Hany, Roland

    2015-01-01

    Organic photodetectors are interesting for low cost, large area optical sensing applications. Combining organic semiconductors with discrete absorption bands outside the visible wavelength range with transparent and conductive electrodes allows for the fabrication of visibly transparent photodetectors. Visibly transparent photodetectors can have far reaching impact in a number of areas including smart displays, window-integrated electronic circuits and sensors. Here, we demonstrate a near-infrared sensitive, visibly transparent organic photodetector with a very high average visible transmittance of 68.9%. The transmitted light of the photodetector under solar irradiation exhibits excellent transparency colour perception and rendering capabilities. At a wavelength of 850?nm and at ?1?V bias, the photoconversion efficiency is 17% and the specific detectivity is 1012 Jones. Large area photodetectors with an area of 1.6?cm2 are demonstrated. PMID:25803320

  7. Transparent organic photodetector using a near-infrared absorbing cyanine dye.

    PubMed

    Zhang, Hui; Jenatsch, Sandra; De Jonghe, Jelissa; Nüesch, Frank; Steim, Roland; Véron, Anna C; Hany, Roland

    2015-01-01

    Organic photodetectors are interesting for low cost, large area optical sensing applications. Combining organic semiconductors with discrete absorption bands outside the visible wavelength range with transparent and conductive electrodes allows for the fabrication of visibly transparent photodetectors. Visibly transparent photodetectors can have far reaching impact in a number of areas including smart displays, window-integrated electronic circuits and sensors. Here, we demonstrate a near-infrared sensitive, visibly transparent organic photodetector with a very high average visible transmittance of 68.9%. The transmitted light of the photodetector under solar irradiation exhibits excellent transparency colour perception and rendering capabilities. At a wavelength of 850?nm and at -1?V bias, the photoconversion efficiency is 17% and the specific detectivity is 10(12) Jones. Large area photodetectors with an area of 1.6?cm(2) are demonstrated. PMID:25803320

  8. Dye sensitization of photoconductivity of polycrystalline silicon

    NASA Astrophysics Data System (ADS)

    Goryaev, M. A.

    2015-12-01

    The DC photoconductivity of powder silicon samples with organic dyes applied to the surface of microcrystals was studied. Effective sensitization of photoconductivity in the absorption band of the dyes in the visible part of the spectrum was found.

  9. Synthesis of a Near-Infrared Emitting Squaraine Dye in an Undergraduate Organic Laboratory

    ERIC Educational Resources Information Center

    Marks, Patrick; Levine, Mindy

    2012-01-01

    Squaraines are a class of organic fluorophores that possess unique photophysical properties, including strong near-infrared absorption and emission. The synthesis of many squaraines involves the condensation of an electron-rich aromatic ring with squaric acid. These reactions are generally refluxed overnight in a benzene-butanol solvent mixture.…

  10. Photocatalytic degradation of indigo carmine by hydrothermally synthesized Bi?MoO ? in presence of EDTA.

    PubMed

    Sánchez Trinidad, C; Martínez-de la Cruz, A; López Cuéllar, E

    2015-01-01

    Bi2MoO6 oxide was synthesized by hydrothermal reaction in the presence of EDTA under different experimental conditions (time of reaction and EDTA concentration) in order to obtain materials with specific textural properties. It was determined that the addition of EDTA influences the final physical properties of Bi2MoO6. The photocatalytic activity of Bi2MoO6 samples was evaluated in the degradation reaction of indigo carmine (IC) in aqueous solution under solar radiation type. The best results as photocatalyst were obtained with the sample hydrothermally synthesized at 150 ºC for 4h in presence of a 0.031 M EDTA solution. This sample was able to whiten a solution of IC in a 94% after 120 min of lamp irradiation with t 1/2?=?31 min. In general, the samples prepared with lower concentrations of EDTA were the best photocatalysts. A gradual decrease in the activity was observed in the samples prepared with the same EDTA concentration as was increased in the reaction time. Beyond differences in morphology and textural properties of the samples prepared, the presence of EDTA by-products on the samples and the decomposition degree of it were important factors in determining the activity of the photocatalysts. Analysis of total organic carbon (TOC) of samples irradiated for 100 h confirmed that Bi2MoO6 oxide is able to mineralize the complex organic molecule of IC to CO2 and H2O in 55 %. PMID:24865501

  11. Potassium induced stitching of a flexible tripodal ligand into a bi-metallic two-dimensional coordination polymer for photo-degradation of organic dyes.

    PubMed

    Bhardwaj, Vimal K

    2015-05-21

    A novel strategy for the stitching of a tripodal ligand into a bi-metallic two-dimensional (2D) coordination polymer has been reported. The reaction of 5-nitrosalicylaldehyde based ligand H3L with nickel acetate resulted in the metal functionalized 2D extended network via potassium induced activation of the nitro group of the ligand. The compound is highly active towards photo-degradation of organic dyes. PMID:25900142

  12. Modeling materials and processes in hybrid/organic photovoltaics: from dye-sensitized to perovskite solar cells.

    PubMed

    De Angelis, Filippo

    2014-11-18

    CONSPECTUS: Over the last 2 decades, researchers have invested enormous research effort into hybrid/organic photovoltaics, leading to the recent launch of the first commercial products that use this technology. Dye-sensitized solar cells (DSCs) have shown clear advantages over competing technologies. The top certified efficiency of DSCs exceeds 11%, and the laboratory-cell efficiency is greater than 13%. In 2012, the first reports of high efficiency solid-state DSCs based on organohalide lead perovskites completely revolutionized the field. These materials are used as light absorbers in DSCs and as light-harvesting materials and electron conductors in meso-superstructured and flat heterojunction solar cells and show certified efficiencies that exceed 17%. To effectively compete with conventional photovoltaics, emerging technologies such as DSCs need to achieve higher efficiency and stability, while maintaining low production costs. Many of the advances in the DSC field have relied on the computational design and screening of new materials, with researchers examining material characteristics that can improve device performance or stability. Suitable modeling strategies allow researchers to observe the otherwise inaccessible but crucial heterointerfaces that control the operation of DSCs, offering the opportunity to develop new and more efficient materials and optimize processes. In this Account, we present a unified view of recent computational modeling research examining DSCs, illustrating how the principles and simulation tools used for these systems can also be adapted to study the emerging field of perovskite solar cells. Researchers have widely applied first-principles modeling to the DSC field and, more recently, to perovskite-based solar cells. DFT/TDDFT methods provide the basic framework to describe most of the desired materials and interfacial properties, and Car-Parrinello molecular dynamics allow researchers the further ability to sample local minima and dynamical fluctuations at finite temperatures. However, conventional DFT/TDDFT has some limitations, which can be overcome in part by tailored solutions or using many body perturbation theory within the GW approach, which is however more computationally intensive. Relativistic effects, such as spin-orbit coupling, are also included in simulations since they are fundamental for addressing systems that contain heavy atoms. We illustrate the performance of the proposed simulation toolbox along with the fundamental modeling strategies using selected examples of relevant isolated device constituents, including dye and perovskite absorbers, metal-oxide surfaces and nanoparticles, and hole transporters. We critically assess the accuracy of various computational approaches against the related experimental data. We analyze the representative interfaces that control the operational mechanism of the devices, including dye-sensitized TiO2/hole transporter and organohalide lead perovskite/TiO2, and the results reveal fundamental aspects of the device's operational mechanism. Although the modeling of DSCs is relatively mature, the recent "perovskite storm" has presented new problems and new modeling challenges, such as understanding exciton formation and dissociation at interfaces and carrier recombination in these materials. PMID:24856085

  13. Understanding flocculation mechanism of graphene oxide for organic dyes from water: Experimental and molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Li, Peng; Xiao, Hang; Zhang, Yayun; Shi, Xiaoyang; Lü, Xiaomeng; Chen, Xi

    2015-11-01

    Flocculation treatment processes play an important role in water and wastewater pretreatment. Here we investigate experimentally and theoretically the possibility of using graphene oxide (GO) as a flocculant to remove methylene blue (MB) from water. Experimental results show that GO can remove almost all MB from aqueous solutions at its optimal dosages and molecular dynamics simulations indicate that MB cations quickly congregate around GO in water. Furthermore, PIXEL energy contribution analysis reveals that most of the strong interactions between GO and MB are of a van der Waals (London dispersion) character. These results offer new insights for shedding light on the molecular mechanism of interaction between GO and organic pollutants.

  14. Influence of synthetic and natural food dyes on activities of CYP2A6, UGT1A6, and UGT2B7.

    PubMed

    Kuno, Nayumi; Mizutani, Takaharu

    2005-08-27

    Synthetic or natural food dyes are typical xenobiotics, as are drugs and pollutants. After ingestion, part of these dyes may be absorbed and metabolized by phase I and II drug-metabolizing enzymes and excreted by transporters of phase III enzymes. However, there is little information regarding the metabolism of these dyes. It was investigated whether these dyes are substrates for CYP2A6 and UDP-glucuronosyltransferase (UGT). The in vitro inhibition of drug-metabolizing enzymes by these dyes was also examined. The synthetic food dyes studied were amaranth (food red no. 2), erythrosine B (food red no. 3), allura red (food red no. 40), new coccine (food red no. 102), acid red (food red no. 106), tartrazine (food Yellow no. 4), sunset yellow FCF (food yellow no. 5), brilliant blue FCF (food blue no. 1), and indigo carmine (food blue no. 2). The natural additive dyes studied were extracts from purple sweet potato, purple corn, cochineal, monascus, grape skin, elderberry, red beet, gardenia, and curthamus. Data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. Only indigo carmine inhibited CYP2A6 in a noncompetitive manner, while erythrosine B inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). In the natural additive dyes just listed, only monascus inhibited UGT1A6 and UGT2B7. PMID:16009655

  15. Facile and Scalable Preparation of Graphene Oxide-Based Magnetic Hybrids for Fast and Highly Efficient Removal of Organic Dyes

    E-print Network

    Jiao, Tifeng

    This study reports the facile preparation and the dye removal efficiency of nanohybrids composed of graphene oxide (GO) and Fe[subscript 3]O[subscript 4] nanoparticles with various geometrical structures. In comparison to ...

  16. Advanced treatment of textile dyeing secondary effluent using magnetic anion exchange resin and its effect on organic fouling in subsequent RO membrane.

    PubMed

    Yang, Cheng; Li, Li; Shi, Jialu; Long, Chao; Li, Aimin

    2015-03-01

    Strict regulations are forcing dyeing factory to upgrade existing waste treatment system. In this study, advanced treatment of dyeing secondary effluent by magnetic anion exchange resin (NDMP) was investigated and compared with ultrafiltration (UF); NDMP as a pre-treatment of reverse osmosis (RO) was also studied. NDMP resin (20 mL/L) gave higher removal of dissolved organic carbon (DOC) (83.9%) and colority (94.9%) than UF with a cut-off of 10 kDa (only 48.6% and 44.1%, respectively), showing that NDMP treatment was effective to meet the stringent discharge limit of DOC and colority. Besides, NDMP resin (20 mL/L) as a pretreatment of RO increased the permeate flux by 12.5% and reduced irreversible membrane fouling by 6.6%, but UF pretreatment did not mitigate RO membrane fouling. The results of excitation-emission matrix fluorescence spectra and resin fractions showed that NDMP had more efficient removal than UF for transphilic acid and hydrophilic fraction, such as protein-like organic matters and soluble microbial products, which contributed to a significant proportion of RO membrane fouling. In sum, NDMP resin treatment not only gave effective removal of DOC and colority of dyeing secondary effluent, but exhibited some improvement for RO membrane flux and irreversible fouling. PMID:25463217

  17. A cascaded QSAR model for efficient prediction of overall power conversion efficiency of all-organic dye-sensitized solar cells.

    PubMed

    Li, Hongzhi; Zhong, Ziyan; Li, Lin; Gao, Rui; Cui, Jingxia; Gao, Ting; Hu, Li Hong; Lu, Yinghua; Su, Zhong-Min; Li, Hui

    2015-05-30

    A cascaded model is proposed to establish the quantitative structure-activity relationship (QSAR) between the overall power conversion efficiency (PCE) and quantum chemical molecular descriptors of all-organic dye sensitizers. The cascaded model is a two-level network in which the outputs of the first level (JSC, VOC, and FF) are the inputs of the second level, and the ultimate end-point is the overall PCE of dye-sensitized solar cells (DSSCs). The model combines quantum chemical methods and machine learning methods, further including quantum chemical calculations, data division, feature selection, regression, and validation steps. To improve the efficiency of the model and reduce the redundancy and noise of the molecular descriptors, six feature selection methods (multiple linear regression, genetic algorithms, mean impact value, forward selection, backward elimination, and +n-m algorithm) are used with the support vector machine. The best established cascaded model predicts the PCE values of DSSCs with a MAE of 0.57 (%), which is about 10% of the mean value PCE (5.62%). The validation parameters according to the OECD principles are R(2) (0.75), Q(2) (0.77), and Qcv2 (0.76), which demonstrate the great goodness-of-fit, predictivity, and robustness of the model. Additionally, the applicability domain of the cascaded QSAR model is defined for further application. This study demonstrates that the established cascaded model is able to effectively predict the PCE for organic dye sensitizers with very low cost and relatively high accuracy, providing a useful tool for the design of dye sensitizers with high PCE. PMID:25773984

  18. [Determination of synthetic food dyes in food by capillary electrophoresis].

    PubMed

    Ishikawa, Fusako; Oishi, Mitsuo; Kimura, Keisuke; Yasui, Akiko; Saito, Kazuo

    2004-06-01

    A method for the determination of 12 synthetic food dyes (Amaranth, Erythrosine, Allura Red AC, New Coccine, Phloxine, Rose Bengal, Acid Red, Tartrazine, Sunset Yellow FCF, Fast Green FCF, Brilliant Blue FCF, Indigo Carmine) in food was developed using capillary electrophoresis (CE) with photodiode array detection. The dyes were extracted with water and 0.5% ammonia-ethanol (1:1) mixture, and cleaned up using solid-phase extraction (Sep-Pak Plus tC18). The dyes were eluted with methanol from the cartridge. The dyes were separated by CE on a bubble cell fused-silica capillary (72 cm to the detector, 75 microm i.d.) using 20% acetonitrile in a mixture of 10 mmol/L potassium phosphate, monobasic and 5 mmol/L sodium carbonate (pH 10.0) as the running buffer. Identifications of the dyes were performed on the basis of the migration time and the absorbance spectrum of each peak. The coefficients of variation of the migration times and the peak areas were 0.28-0.62% and 1.84-4.30%, respectively (n = 5). The identification limits using the absorbance spectra of the dyes were 10 microg/mL for Brilliant Blue FCF and Fast Green FCF, and 5 microg/mL for the other 10 dyes. The recoveries of the 12 dyes from pickles, soft drinks and candies at the level of 10 microg/g were 70.0-101.5%. The method was applied to the analysis of dyes in foods. The dyes detected by CE were in agreement with those detected by paper chromatography. PMID:15468935

  19. High-performance aqueous/organic dye-sensitized solar cells based on sensitizers containing triethylene oxide methyl ether.

    PubMed

    Lin, Ryan Yeh-Yung; Wu, Feng-Ling; Li, Chun-Ting; Chen, Pei-Yu; Ho, Kuo-Chuan; Lin, Jiann T

    2015-08-10

    Metal-free dyes (EO1 to EO4) containing the hydrophilic triethylene oxide methyl ether (TEOME) unit in the spacer have been synthesized and used in dye-sensitized solar cells (DSSCs). Efficient lithium-ion trapping by TEOME results in improved open-circuit voltage (VOC ), leading to excellent conversion efficiency of the cells, ranging from 9.02 to 9.98?% with I(-) /I3 (-) electrolyte in acetonitrile under AM?1.5 illumination. The TEOME unit also enhances the wettability of the dye molecules for application in aqueous-based DSSCs. Aqueous-based DSSCs with a dual TEMPO/iodide electrolyte exhibit high VOC values (0.80-0.88?V) and very promising cell performances of up to 5.97?%. PMID:26098636

  20. Real-time histological imaging of kidneys stained with food dyes using multiphoton microscopy.

    PubMed

    Nagao, Yasuaki; Kimura, Kazushi; Wang, Shujie; Fujiwara, Takeshi; Mizoguchi, Akira

    2015-10-01

    We have developed a real-time imaging technique for diagnosis of kidney diseases which is composed of two steps, staining renal cells safely with food dyes and optical sectioning of living renal tissue to obtain histological images by multiphoton microscopy (MPM). Here, we demonstrated that the MPM imaging with food dyes, including erythrosine and indigo carmine, could be used as fluorescent agents to visualize renal functions and structures such as glomerular bloodstreams, glomerular filtration, and morphology of glomeruli and renal tubules. We also showed that the kidneys of IgA nephropathy model-mice stained with the food dyes presented histopathological characteristics different from those observed in normal kidneys. The use of the food dyes enhances the quality of tissue images obtained by MPM and offers the potential to contribute to a clinical real-time diagnosis of kidney diseases. PMID:26260138

  1. In situ generation of hydroxyl radical by cobalt oxide supported porous carbon enhance removal of refractory organics in tannery dyeing wastewater.

    PubMed

    Karthikeyan, S; Boopathy, R; Sekaran, G

    2015-06-15

    In this study, cobalt oxide doped nanoporous activated carbon (Co-NPAC) was synthesized and used as a heterogeneous catalyst for the Fenton oxidation of organic dye chemicals used in tannery process. The nanoporous activated carbon (NPAC) was prepared from rice husk by precarbonization followed by chemical activation at elevated temperature (600 °C). The cobalt oxide was impregnated onto NPAC and characterized for UV-visible, Fluorescence spectroscopy, FT-IR, HR-TEM, XRD, BET surface area and XPS analyses. The hydroxyl radical generation potential of Co-NPAC from hydrogen peroxide decomposition was identified (?(exi), 320 nm; ?(emi), 450 nm) by Excitation Emission Spectra (EES) analysis. The conditions for the degradation of tannery dyeing wastewater such as, Co-NPAC dose, concentration of H2O2, and temperature were optimized in heterogeneous Fenton oxidation process and the maximum percentage of COD removal was found to be 77%. The treatment of dyes in wastewater was confirmed through UV-Visible spectra, EES and FT-IR spectra analyses. PMID:25733392

  2. Degradation of Dye Wastewater by ns-Pulse DBD Plasma

    NASA Astrophysics Data System (ADS)

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

    2013-09-01

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

  3. 77 FR 22485 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ...The Alcohol and Tobacco Tax and Trade Bureau is revising its regulations to require the disclosure of the presence of cochineal extract and carmine on the labels of any alcohol beverage product containing one or both of these color additives. This rule responds to a final rule issued by the Food and Drug Administration. Consumers who are allergic to cochineal extract or carmine will now be......

  4. ASSESSMENT OF POTENTIAL TOXIC RELEASES FROM LEATHER INDUSTRY DYEING OPERATIONS

    EPA Science Inventory

    The study focused on the organic dyes released to the environment in the wastewaters from leather dyeing operations. Basically, three types of dyes--acid, basic, and direct--are used, although the number of different dyes are well over 50, and the number of formulations used at a...

  5. Adsorption kinetics and isotherm of anionic dyes onto organo-bentonite from single and multisolute systems.

    PubMed

    Shen, Dazhong; Fan, Jianxin; Zhou, Weizhi; Gao, Baoyu; Yue, Qinyan; Kang, Qi

    2009-12-15

    The performances of polydiallydimethylammonium modified bentonite (PDADMA-bentonite) as an adsorbent to remove anionic dyes, namely Acid Scarlet GR (AS-GR), Acid Turquoise Blue 2G (ATB-2G) and Indigo Carmine (IC), were investigated in single, binary and ternary dye systems. In adsorption from single dye solutions with initial concentration of 100 micromol/L, the dosage of PDADMA-bentonite needed to remove 95% dye was 0.42, 0.68 and 0.75 g/L for AS-GR, ATB-2G and IC, respectively. The adsorption isotherms of the three dyes obeyed the Langmuir isotherm model with the equilibrium constants of 0.372, 0.629 and 4.31 L/micromol, the saturation adsorption amount of 176.3, 149.2 and 228.7 micromol/g for ATB-2G, IC and AS-GR, respectively. In adsorption from mixed dye solutions, the isotherm of each individual dye followed an expanded Langmuir isotherm model and the relationship between the total amount of dyes adsorbed and the total equilibrium dye concentration was interpreted well by Langmuir isotherm model. In the region of insufficient dosage of PDADMA-bentonite, the dye with a larger affinity was preferentially removed by adsorption. Desorption was observed in the kinetic curve of the dye with lower affinity on PDADMA-bentonite surface by the competitive adsorption. The kinetics in single dye solution and the total adsorption of dyes in binary and ternary dye systems nicely followed pseudo-second-order kinetic model. PMID:19631461

  6. 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…

  7. Enhancement of a solar photo-Fenton reaction with ferric-organic ligands for the treatment of acrylic-textile dyeing wastewater.

    PubMed

    Soares, Petrick A; Batalha, Mauro; Souza, Selene M A Guelli U; Boaventura, Rui A R; Vilar, Vítor J P

    2015-04-01

    Literature describes a kinetic mineralization profile for most of acrylic-textile dyeing wastewaters using a photo-Fenton reaction characterized by a slow degradation process and high reactants consumption. This work tries to elucidate that the slow decay on DOC concentration is associated with the formation of stable complexes between Fe(3+) and textile auxiliary products, limiting the photoreduction of Fe(3+). This work also evaluates the enhancement of a solar photo-Fenton reaction through the use of different ferric-organic ligands applied to the treatment of a simulated acrylic-textile dyeing wastewater, as a pre-oxidation step to enhance its biodegradability. The photo-Fenton reaction was negatively affected by two dyeing auxiliary products: i) Sera(®) Tard A-AS, a surfactant mainly composed of alkyl dimethyl benzyl ammonium chloride and ii) Sera(®) Sperse M-IW, a dispersing agent composed of polyglycol solvents. The catalytic activity of the organic ligands toward the ferrous-catalysed system followed this order: Fe(III)-Oxalate > Fe(III)-Citrate > Fe(III)-EDDS, and all were better than the traditional photo-Fenton reaction. Different design parameters such as iron concentration, pH, temperature, flow conditions, UV irradiance and H2O2 addition strategy and dose were evaluated. The ferrioxalate induced photo-Fenton process presented the best results, achieving 87% mineralization after 9.3 kJUV L(-1) and allowing to work until near neutral pH values. As expected, the biodegradability of the textile wastewater was significantly enhanced during the photo-Fenton treatment, achieving a value of 73%, consuming 32.4 mM of H2O2 and 5.7 kJUV L(-1). PMID:25618444

  8. Organic Fluorescent Dyes Supported on Activated Boron Nitride: A Promising Blue Light Excited Phosphors for High-Performance White Light-Emitting Diodes

    PubMed Central

    Li, Jie; Lin, Jing; Huang, Yang; Xu, Xuewen; Liu, Zhenya; Xue, Yanming; Ding, Xiaoxia; Luo, Han; Jin, Peng; Zhang, Jun; Zou, Jin; Tang, Chengchun

    2015-01-01

    We report an effective and rare-earth free light conversion material synthesized via a facile fabrication route, in which organic fluorescent dyes, i.e. Rhodamine B (RhB) and fluorescein isothiocyanate (FITC) are embedded into activated boron nitride (?BN) to form a composite phosphor. The composite phosphor shows highly efficient Förster resonance energy transfer and greatly improved thermal stability, and can emit at broad visible wavelengths of 500–650?nm under the 466?nm blue-light excitation. By packaging of the composite phosphors and a blue light-emitting diode (LED) chip with transparent epoxy resin, white LED with excellent thermal conductivity, current stability and optical performance can be realized, i.e. a thermal conductivity of 0.36?W/mk, a Commission Internationale de 1'Eclairage color coordinates of (0.32, 0.34), and a luminous efficiency of 21.6?lm·W?1. Our research opens the door toward to the practical long-life organic fluorescent dyes-based white LEDs. PMID:25682730

  9. Nickel Nanoparticle-Decorated Porous Carbons for Highly Active Catalytic Reduction of Organic Dyes and Sensitive Detection of Hg(II) Ions.

    PubMed

    Veerakumar, Pitchaimani; Chen, Shen-Ming; Madhu, Rajesh; Veeramani, Vediyappan; Hung, Chin-Te; Liu, Shang-Bin

    2015-11-11

    High surface area carbon porous materials (CPMs) synthesized by the direct template method via self-assembly of polymerized phloroglucinol-formaldehyde resol around a triblock copolymer template were used as supports for nickel nanoparticles (Ni NPs). The Ni/CPM materials fabricated through a microwave-assisted heating procedure have been characterized by various analytical and spectroscopic techniques, such as X-ray diffraction, field emission transmission electron microscopy, vibrating sample magnetometry, gas physisorption/chemisorption, thermogravimetric analysis, and Raman, Fourier-transform infrared, and X-ray photon spectroscopies. Results obtained from ultraviolet-visible (UV-vis) spectroscopy demonstrated that the supported Ni/CPM catalysts exhibit superior activity for catalytic reduction of organic dyes, such as methylene blue (MB) and rhodamine B (RhB). Further electrochemical measurements by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) also revealed that the Ni/CPM-modified electrodes showed excellent sensitivity (59.6 ?A ?M(-1) cm(-2)) and a relatively low detection limit (2.1 nM) toward the detection of Hg(II) ion. The system has also been successfully applied for the detection of mercuric ion in real sea fish samples. The Ni/CPM nanocomposite represents a robust, user-friendly, and highly effective system with prospective practical applications for catalytic reduction of organic dyes as well as trace level detection of heavy metals. PMID:26479076

  10. Green synthesis of AgI-reduced graphene oxide nanocomposites: Toward enhanced visible-light photocatalytic activity for organic dye removal

    NASA Astrophysics Data System (ADS)

    Reddy, D. Amaranatha; Lee, Seunghee; Choi, Jiha; Park, Seonhwa; Ma, Rory; Yang, Haesik; Kim, Tae Kyu

    2015-06-01

    Novel reduced graphene oxide (RGO) enwrapped AgI nanocomposites were successfully fabricated by a facile template-free ultrasound-assisted method at room temperature. The structural, morphological, and optical studies demonstrate that the obtained nanostructures have good crystallinity and that the graphene nanosheets are decorated densely with AgI nanostructures. The photocatalytic activity of the composite was evaluated by the degradation of an organic dye, Rhodamine B (RhB), under visible-light irradiation. The results indicate that AgI with incorporated graphene exhibited much higher photocatalytic activity than the pure AgI due to the improved separation efficiency of the photogenerated carriers and that it prolonged the lifetime of the electron-hole pairs due to the chemical bonding between AgI and graphene. AgI (0.4 mg mL-1 of graphene oxide) nanocomposites displayed the highest photocatalytic degradation efficiency and the corresponding catalytic efficiencies within 70 min were ?96%. Moreover, with the assistance of H2O2 the photocatalytic ability of the as-obtained AgI-RGO nanocomposites was enhanced. The corresponding catalytic efficiencies within 30 min were ?96.8% (for 1 mL H2O2) under the same irradiation conditions. The excellent visible-light photocatalytic efficiency and luminescence properties make the AgI-RGO nanocomposites promising candidates for the removal of organic dyes for water purification and enable their application in near-UV white LEDs.

  11. Solution-processable, photo-stable, low-threshold, and broadly tunable thin film organic lasers based on novel high-performing laser dyes

    NASA Astrophysics Data System (ADS)

    Díaz-García, María. A.; Morales-Vidal, Marta; Ramírez, Manuel G.; Villalvilla, José M.; Boj, Pedro G.; Quintana, José A.; Retolaza, A.; Merino, S.

    2015-09-01

    Thin film organic lasers (TFOLs) represent a new generation of inexpensive, mechanically flexible devices with demonstrated applicability in numerous applications in the fields of spectroscopy, optical communications and sensing requiring an organic, efficient, stable, wavelength-tunable and solution-processable laser material. A distributed feedback (DFB) laser is a particularly attractive TFOL because it shows single mode emission, low pump energy, easy integration with other devices, mechanical flexibility and potentially low production cost. Here, amplified spontaneous emission (ASE) and DFB laser applications of novel high performing perylene dyes and p-phenylenevinylene (PV) oligomers, both dispersed in thermoplastic polymers, used as passive matrixes, are reported. Second-order DFB lasers based on these materials show single mode emission, wavelength tunability across the visible spectrum, operational lifetimes of >105 pump pulses, larger than previously reported PV oligomers or polymers, and thresholds close to pumping requirements with light-emitting diodes.

  12. A simple method for determination of carmine in food samples based on cloud point extraction and spectrophotometric detection.

    PubMed

    Heydari, Rouhollah; Hosseini, Mohammad; Zarabi, Sanaz

    2015-11-01

    In this paper, a simple and cost effective method was developed for extraction and pre-concentration of carmine in food samples by using cloud point extraction (CPE) prior to its spectrophotometric determination. Carmine was extracted from aqueous solution using Triton X-100 as extracting solvent. The effects of main parameters such as solution pH, surfactant and salt concentrations, incubation time and temperature were investigated and optimized. Calibration graph was linear in the range of 0.04-5.0 ?g mL(-1) of carmine in the initial solution with regression coefficient of 0.9995. The limit of detection (LOD) and limit of quantification were 0.012 and 0.04 ?g mL(-1), respectively. Relative standard deviation (RSD) at low concentration level (0.05 ?g mL(-1)) of carmine was 4.8% (n=7). Recovery values in different concentration levels were in the range of 93.7-105.8%. The obtained results demonstrate the proposed method can be applied satisfactory to determine the carmine in food samples. PMID:26103432

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

    SciTech Connect

    Medhekar, S.; Kumar, R.; Mukherjee, S.; Choubey, R. K.

    2013-02-05

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

  14. Evaluation of the treatment performance of lab-scaled vertical flow constructed wetlands in removal of organic compounds, color and nutrients in azo dye-containing wastewater.

    PubMed

    Dogdu, Gamze; Yalcuk, Arda

    2016-02-01

    The objective of this study is to examine the treatment performance of vertical flow intermittent feeding constructed wetland (VFCW) in removal of organic pollution, nutrients and color in azo-dye containing wastewater. The systems consisted of PVC reactors, some filling materials such as gravel, sand and zeolite and wetland plants including Typha angustifolia and Canna indica. The average treatment efficiency of the systems for COD, color, sulphate, NH4-N, and PO4-P were in the range of 57-63%, 94-99%, 44-48%, 39-44%, and 84-88%, respectively among the VFCW reactors. It is concluded that VFCW reactor system can effectively be used in the treatment of dye-rich wastewater, especially for the removal of color and in the reduction of COD. Biofilm formation and cleavage of azo bonds could be observed by SEM and FTIR results, respectively. Almost similar NH4-N and PO4-P removal were obtained in all reactors by using same amount of zeolite media. PMID:26248021

  15. Bi-anchoring organic sensitizers of type D-(?-A)? comprising thiophene-2-acetonitrile as ?-spacer and malonic acid as electron acceptor for dye sensitized solar cell applications.

    PubMed

    Reddy, Gachumale Saritha; Ramkumar, Sekar; Asiri, Abdullah M; Anandan, Sambandam

    2015-06-15

    Two new bi-anchoring organic sensitizers of type D-(?-A)2 comprising the identical ?-spacer (thiophene-2-acetonitrile) and electron acceptor (malonic acid) but different aryl amine as electron donors (diphenylamine and carbazole) were synthesized, characterized and fabricated metal free dye-sensitized solar cell devices. The intra molecular charge transfer property and electrochemical property of these dyes were investigated by molecular absorption, emission, cyclic voltammetric experiments and in addition, quantum chemical calculation studies were performed to provide sufficient driving force for the electron injection into the conduction band of TiO2 which leads to efficient charge collection. Among the fabricated devices, carbazole based device exhibits high current conversion efficiency (?=4.7%) with a short circuit current density (JSC) 15.3 mA/cm(2), an open circuit photo voltage (VOC) of 0.59 V and a fill factor of 0.44 under AM 1.5 illumination (85 mW/cm(2)) compared to diphenylamine based device. PMID:25801442

  16. Enhanced Electron Lifetimes in Dye-Sensitized Solar Cells Using a Dichromophoric Porphyrin: The Utility of Intermolecular Forces.

    PubMed

    Zhao, Long; Wagner, Pawel; van der Salm, Holly; Gordon, Keith C; Mori, Shogo; Mozer, Attila J

    2015-10-01

    Electron lifetimes in dye-sensitized solar cells employing a porphyrin dye, an organic dye, a 1:1 mixture of the two dyes, and a dichromophoric dye design consisting of the two dyes using a nonconjugated linker were measured, suggesting that the dispersion force of the organic dyes has a significant detrimental effect on the electron lifetime and that the dichromophoric design can be utilized to control the effect of the dispersion force. PMID:26375165

  17. Organic-free Anatase TiO? Paste for Efficient Plastic Dye-Sensitized Solar Cells and Low Temperature Processed Perovskite Solar Cells.

    PubMed

    Fu, Nianqing; Huang, Chun; Liu, Yan; Li, Xing; Lu, Wei; Zhou, Limin; Peng, Feng; Liu, Yanchun; Huang, Haitao

    2015-09-01

    Recently, the synthesis of fine TiO2 paste with organic-free binder emerged as an indispensable technique for plastic photovoltaics due to the low temperature processing requirement. In this study, pure anatase TiO2 nanoparticles and organic-free TiO2-sol were successfully synthesized individually in organic-free solution. By mixing the pure anatase TiO2 with the newly developed TiO2-sol binder, mechanically robust and well-interconnected TiO2 films were prepared via UV-irradiation at low temperature for applications in plastic dye-sensitized solar cells (p-DSSCs). The structural, electrical, and photovoltaic properties of the films as well as the devices were investigated by various techniques. The dye-loading amount of the obtained film is 2.6 times that of the P25 electrodes. As revealed by electrochemical impedance spectroscopy results, the film derived from the as-prepared anatase TiO2 paste (A-TiO2) exhibits much smaller charge transport resistance and lower electron recombination rate than the P25 film, while the introduction of TiO2-sol into the paste can further remarkably decrease the resistance of the produced film (AS-TiO2). The p-DSSCs employing AS-TiO2 photoanode yield a high efficiency up to 7.51%, which is 86% higher than the P25 reference cells and also 31% higher than the A-TiO2 cell. As a proof of concept, the newly developed AS-TiO2 paste was also applied to low temperature processed perovskite solar cells (PSCs), and a promising high efficiency up to 9.95% was achieved. PMID:26284590

  18. TiO2 Immobilized on Manihot Carbon: Optimal Preparation and Evaluation of Its Activity in the Decomposition of Indigo Carmine

    PubMed Central

    Antonio-Cisneros, Cynthia M.; Dávila-Jiménez, Martín M.; Elizalde-González, María P.; García-Díaz, Esmeralda

    2015-01-01

    Applications of carbon-TiO2 materials have attracted attention in nanotechnology due to their synergic effects. We report the immobilization of TiO2 on carbon prepared from residues of the plant Manihot, commercial TiO2 and glycerol. The objective was to obtain a moderate loading of the anatase phase by preserving the carbonaceous external surface and micropores of the composite. Two preparation methods were compared, including mixing dry precursors and immobilization using a glycerol slurry. The evaluation of the micropore blocking was performed using nitrogen adsorption isotherms. The results indicated that it was possible to use Manihot residues and glycerol to prepare an anatase-containing material with a basic surface and a significant SBET value. The activities of the prepared materials were tested in a decomposition assay of indigo carmine. The TiO2/carbon eliminated nearly 100% of the dye under UV irradiation using the optimal conditions found by a Taguchi L4 orthogonal array considering the specific surface, temperature and initial concentration. The reaction was monitored by UV-Vis spectrophotometry and LC-ESI-(Qq)-TOF-MS, enabling the identification of some intermediates. No isatin-5-sulfonic acid was detected after a 60 min photocatalytic reaction, and three sulfonated aromatic amines, including 4-amino-3-hydroxybenzenesulfonic acid, 2-(2-amino-5-sulfophenyl)-2-oxoacetic acid and 2-amino-5-sulfobenzoic acid, were present in the reaction mixture. PMID:25588214

  19. A hydrazone covalent organic polymer based micro-solid phase extraction for online analysis of trace Sudan dyes in food samples.

    PubMed

    Zhang, Chengjiang; Li, Gongke; Zhang, Zhuomin

    2015-11-01

    Covalent organic polymers (COPs) connected by covalent bonds are a new class of porous network materials with large surface area and potential superiority in sample pretreatment. In this study, a new hydrazone linked covalent organic polymer (HL-COP) adsorbent was well-designed and synthesized based on a simple Schiff-base reaction. The condensation of 1,4-phthalaldehyde and 1,3,5-benzenetricarbohydrazide as organic building blocks led to the synthesis of HL-COP with uniform particle size and good adsorption performance. This HL-COP adsorbent with high hydrophobic property and rich stacking ? electrons contained abundant phenyl rings and imine (CN) groups throughout the entire molecular framework. The adsorption mechanism was explored and discussed based on ?-? affinity, hydrophobic effect, hydrogen bonding and electron-donor-acceptor (EDA) interaction, which contributed to its strong recognition affinity to target compounds. Enrichment factors were 305-757 for six Sudan dyes by HL-COP micro-solid phase extraction (?-SPE), indicating its remarkable preconcentration ability. Furthermore, the adsorption amounts by HL-COP ?-SPE were 1.0-11.0 folds as those by three commonly used commercial adsorbents. Then, HL-COP was applied as adsorbent of online ?-SPE coupled with high performance liquid chromatography (HPLC) for enrichment and analysis of trace Sudan dyes in food samples with detection limit of 0.03-0.15?g/L. The method was successfully applied for online analysis of chilli powder and sausage samples. Sudan II and Sudan III in one positive chilli powder sample were actually found and determined with concentrations of 8.3 and 6.8?g/kg, respectively. The recoveries of chilli powder and sausage samples were in range of 75.8-108.2% and 73.8-112.6% with relative standard deviations of 1.2-8.5% and 1.9-9.4% (n=5), respectively. The proposed method was accurate, reliable and convenient for the online simultaneous analysis of trace Sudan dyes in food samples. PMID:26456513

  20. Influence of the Terminal Electron Donor in D-D-?-A Organic Dye-Sensitized Solar Cells: Dithieno[3,2-b:2',3'-d]pyrrole versus Bis(amine).

    PubMed

    Dai, Panpan; Yang, Lin; Liang, Mao; Dong, Huanhuan; Wang, Peng; Zhang, Chunyao; Sun, Zhe; Xue, Song

    2015-10-14

    With respect to the electron-withdrawing acceptors of D-A-?-A organic dyes, reports on the second electron-donating donors for D-D-?-A organic dyes are very limited. Both of the dyes have attracted significant attention in the field of dye-sensitized solar cells (DSCs). In this work, four new D-D-?-A organic dyes with dithieno[3,2-b:2',3'-d]pyrrole (DTP) or bis(amine) donor have been designed and synthesized for a investigation of the influence of the terminal electron donor in D-D-?-A organic dye-sensitized solar cells. It is found that DTP is a promising building block as the terminal electron donor when introduced in the dithiophenepyrrole direction, but not just a good bridge, which exhibits several characteristics: (i) efficiently increasing the maximum molar absorption coefficient and extending the absorption bands; (ii) showing stronger charge transfer interaction as compared with the pyrrole direction; (iii) beneficial to photocurrent generation of DSCs employing cobalt electrolytes. DSCs based on M45 with the Co-phen electrolyte exhibit good light-to-electric energy conversion efficiencies as high as 9.02%, with a short circuit current density (JSC) of 15.3 mA cm(-2), open circuit voltage (VOC) of 867 mV and fill factor (FF) of 0.68 under AM 1.5 illumination (100 mW cm(-2)). The results demonstrate that N,S-heterocycles such as DTP unit could be promising candidates for application in highly efficient DSCs employing cobalt electrolyte. PMID:26394089

  1. THERMOSPRAY IONIZATION AND TANDEM MASS SPECTROMETRY OF DYES

    EPA Science Inventory

    Sixteen commercial dye samples and three liquid wastes from organic pigment and dye manufacture have been characterized without prior chromatography by thermospray ionization and low energy collision-activated dissociation of protonated molecules using a triple quadrupole mass sp...

  2. Circularly Polarized Luminescence by Visible-Light Absorption in a Chiral O-BODIPY Dye: Unprecedented Design of CPL Organic Molecules from Achiral Chromophores

    PubMed Central

    2015-01-01

    Circularly polarized luminescence (CPL) in simple (small, nonaggregated, nonpolymeric) O-BODIPYs (R)-1 and (S)-1 by irradiation with visible light is first detected as proof of the ability of a new structural design to achieve CPL from inherently achiral monochromophore systems in simple organic molecules. The measured level of CPL (|glum|) in solution falls into the usual range of that obtained from other simple organic molecules (10–5–10–2 range), but the latter having more complex architectures since axially chiral chromophores or multichromophore systems are usually required. The new design is based on chirally perturbing the acting achiral chromophore by orthogonally tethering a single axially chiral 1,1?-binaphtyl moiety to it. The latter does not participate as a chromophore in the light-absorption/emission phenomenon. This simple design opens up new perspectives for the future development of new small-sized CPL organic dyes (e.g., those based on other highly luminescent achiral chromophores and/or chirally perturbing moieties), as well as for the improvement of the CPL properties of the organic molecules spanning their use in photonic applications. PMID:24524257

  3. CTAB-assisted synthesis of novel ultrathin MoSe2 nanosheets perpendicular to graphene for the adsorption and photodegradation of organic dyes under visible light.

    PubMed

    Wu, Yuxin; Xu, Mingquan; Chen, Xi; Yang, Shuanglei; Wu, Hanshuo; Pan, Jun; Xiong, Xiang

    2015-12-17

    A novel nanostructure of perpendicular ultrathin MoSe2 nanosheets directly grown on graphene was produced by a facile hydrothermal method in the presence of CTAB. The vertically-oriented and ultrathin MoSe2 nanosheets distribute uniformly on the surface of graphene, and the nanosheets are typically 2-3 layers, which is confirmed by TEM and red shift of the A1g Raman peak. In comparison with pure MoSe2 and MoSe2 nanospheres on graphene, vertically oriented MoSe2 nanosheets on graphene show enhanced organic dye adsorption ability and photocatalytic performance in the degradation of MB, RhB and MO under dark conditions and visible light irradiation. The excellent photocatalytic activity may be contributed by the unique perpendicular MoSe2 nanosheets with fully exposed active edges and hybridized with graphene for reduced electron-hole pair recombination. PMID:26627597

  4. Kinetic isotope effect on the proton-transfer in indigo carmine

    NASA Astrophysics Data System (ADS)

    Iwakura, Izumi; Yabushita, Atsushi; Kobayashi, Takayoshi

    2010-01-01

    We have found that photo-excited indigo carmine causes stepwise proton transfer to generate mono-alcohol intermediate, which immediately returns to the parent molecule [I. Iwakura, A. Yabushita, T. Kobayashi, Chem. Lett. 38 (2009) 1020]. The kinetic isotope effect in the proton transfer of this system has been studied by direct observation of the real-time molecular vibrational amplitude during the reaction including the transition state using a sub-5-fs laser pulse. The kaH/kaD ratio for the proton transfer after photo-excitation is observed to be 1.5 ± 0.1.

  5. Towards modeling of random lasing in dye doped bio-organic based systems: ray-tracing and cellular automaton analysis

    NASA Astrophysics Data System (ADS)

    Mitus, A. C.; Stopa, P.; Zaklukiewicz, W.; Pawlik, G.; Mysliwiec, J.; Kajzar, F.; Rau, I.

    2015-08-01

    One of many photonic applications of biopolymers as functional materials is random lasing resulting from an incorporation of highly luminescent dyes into biopolymeric matrix, which leads to a random but coherent light scattering in amplifying medium. In spite of numerous theoretical and experimental studies the origin of the coherence is still not clear and various scenarios are discussed. In particular, inhomogeneity of biopolymeric layers can hypothetically promote the feedback in the scattering of the emitted light resulting in coherent and incoherent random lasing. In this paper we analyze the light scattering in a model system of scattering centers of circular shapes and various dimensions using ray-tracing techniques. In the second part, which has mostly a tutorial character, we present the approach to the study of random lasing using a cellular automaton model of Wiersma et al.

  6. Dye laser amplifier

    DOEpatents

    Moses, E.I.

    1992-12-01

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

  7. 77 FR 22485 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ...one or both of these color additives. This rule responds to a...products that contain these color additives. DATES: Effective Date...statements relating to age, manufacturing processes, analyses, guarantees...extract and carmine are color additives that are permitted for...

  8. 76 FR 3584 - Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-20

    ... From the Federal Register Online via the Government Printing Office DEPARTMENT OF THE TREASURY Alcohol and Tobacco Tax and Trade Bureau 27 CFR Parts 5 RIN 1513-AB79 Disclosure of Cochineal Extract and Carmine in the Labeling of Wines, Distilled Spirits, and Malt Beverages Correction In proposed...

  9. 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.

  10. Organic dyes with a fused segment comprising benzotriazole and thieno[3,2-b]pyrrole entities as the conjugated spacer for high performance dye-sensitized solar cells.

    PubMed

    Ni, Jen-Shyang; Yen, Yi-Chi; Lin, Jiann T

    2015-12-14

    Sensitizers with a fused segment comprising electron deficient benzotriazole () and electron rich thiophene or thieno[3,2-b]pyrrole entities as the conjugated spacer have been synthesized for dye-sensitized solar cells (DSSCs). The power conversion efficiency (PCE) increases with elongation of the conjugated spacer, and the dye with the dithieno[3,2-b]pyrrolobenzotriazole spacer has the best efficiency of 8.14%, which is comparable with that of an -based DSSC (8.03%). After coadsorbed with 1 mM CDCA, the efficiency was improved to 8.4%. The J-aggregation of the dye results in light harvesting at a longer wavelength spectral region and increasing the photocurrent of the cell. PMID:26452205

  11. Hierarchical Heteroaggregation of Binary Metal-Organic Gels with Tunable Porosity and Mixed Valence Metal Sites for Removal of Dyes in Water

    PubMed Central

    Mahmood, Asif; Xia, Wei; Mahmood, Nasir; Wang, Qingfei; Zou, Ruqiang

    2015-01-01

    Hierarchical heteronuclear metal-organic gels (MOGs) based on iron (Fe) and aluminium (Al) metal-organic framework (MOF) backbones bridged by tri-carboxylate ligands have firstly been synthesized by simple solvothermal method. Monometallic MOGs based on Fe or Al give homogenous monoliths, which have been tuned by introduction of heterogeneity in the system (mismatched growth). The developed gels demonstrate that surface areas, pore volumes and pore sizes can be readily tuned by optimizing heterogeneity. The work also elaborates effect of heterogeneity on size of MOG particles which increase substantially with increasing heterogeneity as well as obtaining mixed valence sites in the gels. High surface areas (1861?m2/g) and pore volumes (9.737?cc/g) were obtained for heterogeneous gels (0.5Fe-0.5Al). The large uptakes of dye molecules (290?mg/g rhodamine B and 265?mg/g methyl orange) with fast sorption kinetics in both neutral and acidic mediums show good stability and accessibility of MOG channels (micro and meso-/macropores), further demonstrating their potential applications in catalysis and sorption of large molecules. PMID:26014755

  12. A recyclable and highly active Co{sub 3}O{sub 4} nanoparticles/titanate nanowire catalyst for organic dyes degradation with peroxymonosulfate

    SciTech Connect

    Chen, Zhili; Chen, Shihua; Li, Yonghe; Si, Xiaolei; Huang, Jun; Massey, Sylvain; Chen, Guangliang

    2014-09-15

    Sodium ions of TNWs were exchanged with hydrogen ions, and this protocol was very suitable for capturing high density of cobalt ions. Meanwhile, the fabricated Co{sub 3}O{sub 4}/TNWs nano-material presented a highly catalytic and stable activity for dye degradation. - Highlights: • Co{sub 3}O{sub 4} nanoparticles were deposited on the pretreated TNWs surface. • The TNWs treated by hydrogen ions captures higher density of cobalt ions. • The Co{sub 3}O{sub 4}/TNWs catalyst possesses highly efficiency for dyes degradation with oxone. - Abstract: In this paper, we reported a recyclable and highly active porous catalyst of titanate nanowires (TNWs) coated with well-distributed Co{sub 3}O{sub 4} nanoparticles (NPs) (Co{sub 3}O{sub 4}/TNWs). Sodium ions of TNWs were exchanged with hydrogen ions in the dilute nitric acid, and this protocol was very suitable for capturing cobalt ions. X-ray diffraction (XRD) demonstrated the existence of Co{sub 3}O{sub 4} phase with unique lattice planes, such as (2 2 0), (3 1 1) and (5 1 1). Electron microscopes (FE-SEM and TEM) indicated that the Co{sub 3}O{sub 4} NPs with an average diameter of 22 ± 3 nm were coated uniformly on TNWs surface (average diameter: 37 ± 5.5 nm), and the Co{sub 3}O{sub 4} NPs mainly exposed their (2 2 0) and (2 2 2) active planes. XPS analysis confirms the formation of Co{sub 3}O{sub 4} phase by the presence of Co 2p peaks at 780.1 eV (2p 3/2) and 795.5 eV (2p 1/2). Methylene blue (MB) and other organic dyes (rhodamine B (RhB) and methyl orange (MO)) were chosen as target compounds for catalytic degradation under indoor scattering light. Compared to the original Co{sub 3}O{sub 4}/TNWs catalyst, the catalytic efficiency of nanoscaled catalyst with oxone for MB was about 15 times higher, and the MB solution (10 mg L{sup ?1}) was completely degraded within 8 min. The catalytic activity of recycled catalyst used in the sixth run still remained very active, and the degradation time for MB was only 16 min. The nanosized catalyst also had a high activity for dyes of RhB (10 mg L{sup ?1}) and MO (10 mg L{sup ?1}), as the degradation efficiencies of RhB and MO after 10 min of contact time were about 90.2% and 92.6%, respectively.

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

    SciTech Connect

    Shan Zhichao; Wang Wendeng; Lin Xinping; Ding Hanming Huang Fuqiang

    2008-06-15

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

  14. Post-Assembly Atomic Layer Deposition of Ultrathin Metal-Oxide Coatings Enhances the Performance of an Organic Dye-Sensitized

    E-print Network

    Post-Assembly Atomic Layer Deposition of Ultrathin Metal-Oxide Coatings Enhances the Performance-sensitized solar cells (DSCs), atomic layer deposition (ALD), dye aggregation, post-treatment, interfacial electron chemistry,13-20 adsorbed-dye encapsulation by polymer,21-23 silica,24 or atomic layer deposition (ALD),25

  15. Highly-efficient dye-sensitized solar cells with collaborative sensitization by silyl-anchor and carboxy-anchor dyes.

    PubMed

    Kakiage, Kenji; Aoyama, Yohei; Yano, Toru; Oya, Keiji; Fujisawa, Jun-Ichi; Hanaya, Minoru

    2015-11-14

    In dye-sensitized solar cells co-photosensitized with an alkoxysilyl-anchor dye ADEKA-1 and a carboxy-anchor organic dye LEG4, LEG4 was revealed to work collaboratively by enhancing the electron injection from the light-excited dyes to the TiO2 electrodes, and the cells exhibited a high conversion efficiency of over 14% under one sun illumination. PMID:26393334

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

    SciTech Connect

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

    2006-04-01

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

  17. Accidental injection of patent blue dye during gynaecological surgery: Lack of knowledge constitutes a system error.

    PubMed

    Laukaityte, Edita; Bruyère, Marie; Bull, Amanda; Benhamou, Dan

    2015-02-01

    The authors report a case in which an intravenous injection of Patent Blue V dye instead of Indigo Carmine was given during routine gynaecological surgery. The patient presented with temporary arterial (spurious) desaturation and skin discoloration over a 48-hour period. Pharmacological differences between these dyes are described. Root cause analysis based on the ALARM (Association of Litigation and Risk Management) model is presented. The authors emphasise that use of this model should not be limited solely to describing and correcting well known systems errors such as working conditions or teamwork and communication. Furthermore, they conclude that insufficient knowledge must also be recognised as a systems error and as such should be sought out and corrected using similar strategies to those used to discover other contributory factors, without allocation of blame to any individual. PMID:25829317

  18. New organic donor-acceptor-?-acceptor sensitizers for efficient dye-sensitized solar cells and photocatalytic hydrogen evolution under visible-light irradiation.

    PubMed

    Li, Xing; Cui, Shicong; Wang, Dan; Zhou, Ying; Zhou, Hao; Hu, Yue; Liu, Jin-Gang; Long, Yitao; Wu, Wenjun; Hua, Jianli; Tian, He

    2014-10-01

    Two organic donor-acceptor-?-acceptor (D-A-?-A) sensitizers (AQ and AP), containing quinoxaline/pyrido[3,4-b]pyrazine as the auxiliary acceptor, have been. Through fine-tuning of the auxiliary acceptor, a higher designed and synthesized photoelectric conversion efficiency of 6.02% for the AQ-based dye-sensitized solar cells under standard global AM1.5 solar conditions was achieved. Also, it was found that AQ-Pt/TiO2 photocatalysts displayed a better rate of H2 evolution under visible-light irradiation (420 nm

  19. Platinum-Free Counter Electrode Comprised of Metal-Organic-Framework (MOF)-Derived Cobalt Sulfide Nanoparticles for Efficient Dye-Sensitized Solar Cells (DSSCs)

    PubMed Central

    Hsu, Shao-Hui; Li, Chun-Ting; Chien, Heng-Ta; Salunkhe, Rahul R.; Suzuki, Norihiro; Yamauchi, Yusuke; Ho, Kuo-Chuan; Wu, Kevin C.-W.

    2014-01-01

    We fabricated a highly efficient (with a solar-to-electricity conversion efficiency (?) of 8.1%) Pt-free dye-sensitized solar cell (DSSC). The counter electrode was made of cobalt sulfide (CoS) nanoparticles synthesized via surfactant-assisted preparation of a metal organic framework, ZIF-67, with controllable particle sizes (50 to 320?nm) and subsequent oxidation and sulfide conversion. In contrast to conventional Pt counter electrodes, the synthesized CoS nanoparticles exhibited higher external surface areas and roughness factors, as evidenced by X-ray diffraction (XRD), scanning electron microscopy (SEM) element mapping, and electrochemical analysis. Incident photon-to-current conversion efficiency (IPCE) results showed an increase in the open circuit voltage (VOC) and a decrease in the short-circuit photocurrent density (Jsc) for CoS-based DSSCs compared to Pt-based DSSCs, resulting in a similar power conversion efficiency. The CoS-based DSSC fabricated in the study show great potential for economically friendly production of Pt-free DSSCs. PMID:25382139

  20. Photoinduced electron transfer (PET) versus excimer formation in supramolecular p/n-heterojunctions of perylene bisimide dyes and implications for organic photovoltaics.

    PubMed

    Nowak-Król, Agnieszka; Fimmel, Benjamin; Son, Minjung; Kim, Dongho; Würthner, Frank

    2015-12-22

    Foldamer systems comprised of two perylene bisimide (PBI) dyes attached to the conjugated backbones of 1,2-bis(phenylethynyl)benzene and phenylethynyl-bis(phenylene)indane, respectively, were synthesized and investigated with regard to their solvent-dependent properties. UV/Vis absorption and steady-state fluorescence spectra show that both foldamers exist predominantly in a folded H-aggregated state consisting of ?-?-stacked PBIs in THF and in more random conformations with weaker excitonic coupling between the PBIs in chloroform. Time-resolved fluorescence spectroscopy and transient absorption spectroscopy reveal entirely different relaxation pathways for the photoexcited molecules in the given solvents, i.e. photoinduced electron transfer leading to charge separated states for the open conformations (in chloroform) and relaxation into excimer states with red-shifted emission for the stacked conformations (in THF). Supported by redox data from cyclic voltammetry and Rehm-Weller analysis we could relate the processes occurring in these solution-phase model systems to the elementary processes in organic solar cells. Accordingly, only if relaxation pathways such as excimer formation are strictly avoided in molecular semiconductor materials, excitons may diffuse over larger distances to the heterojunction interface and produce photocurrent via the formation of electron/hole pairs by photoinduced electron transfer. PMID:26399996

  1. Adsorption of dyes on Sahara desert sand.

    PubMed

    Varlikli, Canan; Bekiari, Vlasoula; Kus, Mahmut; Boduroglu, Numan; Oner, Ilker; Lianos, Panagiotis; Lyberatos, Gerasimos; Icli, Siddik

    2009-10-15

    Sahara desert sand (SaDeS) was employed as a mineral sorbent for retaining organic dyes from aqueous solutions. Natural sand has demonstrated a strong affinity for organic dyes but significantly lost its adsorption capacity when it was washed with water. Therefore, characterization of both natural and water washed sand was performed by XRD, BET, SEM and FTIR techniques. It was found that water-soluble kyanite, which is detected in natural sand, is the dominant factor affecting adsorbance of cationic dyes. The sand adsorbs over 75% of cationic dyes but less than 21% for anionic ones. Among the dyes studied, Methylene Blue (MB) demonstrated the strongest affinity for Sahara desert sand (Q(e)=11.98 mg/g, for initial dye solution concentration 3.5 x 10(-5)mol/L). The effects of initial dye concentration, the amount of the adsorbent, the temperature and the pH of the solution on adsorption capacity were tested by using Methylene Blue as model dye. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were applied. It was concluded that adsorption of Methylene Blue on Sahara desert sand followed pseudo-second order kinetics. Gibbs free energy, enthalpy change and entropy change were calculated and found -6411 J/mol, -30360 J/mol and -76.58 J/mol K, respectively. These values indicate that the adsorption is an exothermic process and has a spontaneous nature at low temperatures. PMID:19515485

  2. Adsorption of porphyrin and carminic acid on TiO2 nanoparticles: A photo-active nano-hybrid material for hybrid bulk heterojunction solar cells.

    PubMed

    Munir, Shamsa; Shah, Syed Mujtaba; Hussain, Hazrat; Siddiq, Muhammad

    2015-12-01

    A photo-active nano-hybrid material consisting of titania nanoparticles, carminic acid, and sulphonic acid functionalized porphyrin is reported here. In an attempt to extend the absorption spectrum of titania to visible region by co-adsorbing carminic acid and sulphonic acid functionalized porphyrin on its surface. Interesting changes in the UV-visible and fluorescence spectra were noticed. The adsorption of carminic acid resulted in the formation of charge transfer complex with titania nanoparticles. This was confirmed by the electronic absorption and fluorescence emission spectroscopies. Chemisorption of porphyrin on the carminic acid functionalized titania further boosted the charge transfer effect. This was noticed by the increase in intensity and width of the charge transfer absorption and emission bands. Energy level diagram showed that the interaction among the constituents of the nano-hybrid assembly permitted the flow of electron in a cascade manner from carminic acid to TiO2.This also allowed direct flow of electrons either from carminic acid or porphyrin toward titania. The material was used as an active blend in hybrid bulk heterojunction solar cells. Co-functionalized TiO2-based devices were found 3.5 times more efficient than the reference device but morphology of the device proved a major setback. PMID:26555643

  3. Method of dye removal for the textile industry

    SciTech Connect

    Stone, M.L.

    2000-07-25

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

  4. Method of dye removal for the textile industry

    DOEpatents

    Stone, Mark L. (Idaho Falls, ID)

    2000-01-01

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

  5. Low temperature (150?°C) fabrication of high-performance TiO{sub 2} films for dye-sensitized solar cells using ultraviolet light and plasma treatments of TiO{sub 2} paste containing organic binder

    SciTech Connect

    Zen, Shungo Ono, Ryo; Inoue, Yuki

    2015-03-14

    Dye-sensitized solar cells (DSSCs) require annealing of TiO{sub 2} photoelectrodes at 450?°C to 550?°C. However, such high-temperature annealing is unfavorable because it limits the use of materials that cannot withstand high temperatures, such as plastic substrates. In our previous paper, a low-temperature annealing technique of TiO{sub 2} photoelectrodes using ultraviolet light and dielectric barrier discharge treatments was proposed to reduce the annealing temperature from 450?°C to 150?°C for a TiO{sub 2} paste containing an organic binder. Here, we measure the electron diffusion length in the TiO{sub 2} film, the amount of dye adsorption on the TiO{sub 2} film, and the sheet resistance of a glass substrate of samples manufactured with the 150?°C annealing method, and we discuss the effect that the 150?°C annealing method has on those properties of DSSCs.

  6. Low temperature (150 °C) fabrication of high-performance TiO2 films for dye-sensitized solar cells using ultraviolet light and plasma treatments of TiO2 paste containing organic binder

    NASA Astrophysics Data System (ADS)

    Zen, Shungo; Inoue, Yuki; Ono, Ryo

    2015-03-01

    Dye-sensitized solar cells (DSSCs) require annealing of TiO2 photoelectrodes at 450 °C to 550 °C. However, such high-temperature annealing is unfavorable because it limits the use of materials that cannot withstand high temperatures, such as plastic substrates. In our previous paper, a low-temperature annealing technique of TiO2 photoelectrodes using ultraviolet light and dielectric barrier discharge treatments was proposed to reduce the annealing temperature from 450 °C to 150 °C for a TiO2 paste containing an organic binder. Here, we measure the electron diffusion length in the TiO2 film, the amount of dye adsorption on the TiO2 film, and the sheet resistance of a glass substrate of samples manufactured with the 150 °C annealing method, and we discuss the effect that the 150 °C annealing method has on those properties of DSSCs.

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

    PubMed

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

    2013-01-01

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

  8. Discoloration of Indigo Carmine Using Aqueous Extracts from Vegetables and Vegetable Residues as Enzyme Sources

    PubMed Central

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

    2013-01-01

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

  9. Organic solvent-free air-assisted liquid-liquid microextraction for optimized extraction of illegal azo-based dyes and their main metabolite from spices, cosmetics and human bio-fluid samples in one step.

    PubMed

    Barfi, Behruz; Asghari, Alireza; Rajabi, Maryam; Sabzalian, Sedigheh

    2015-08-15

    Air-assisted liquid-liquid microextraction (AALLME) has unique capabilities to develop as an organic solvent-free and one-step microextraction method, applying ionic-liquids as extraction solvent and avoiding centrifugation step. Herein, a novel and simple eco-friendly method, termed one-step air-assisted liquid-liquid microextraction (OS-AALLME), was developed to extract some illegal azo-based dyes (including Sudan I to IV, and Orange G) from food and cosmetic products. A series of experiments were investigated to achieve the most favorable conditions (including extraction solvent: 77?L of 1-Hexyl-3-methylimidazolium hexafluorophosphate; sample pH 6.3, without salt addition; and extraction cycles: 25 during 100s of sonication) using a central composite design strategy. Under these conditions, limits of detection, linear dynamic ranges, enrichment factors and consumptive indices were in the range of 3.9-84.8ngmL(-1), 0.013-3.1?gmL(-1), 33-39, and 0.13-0.15, respectively. The results showed that -as well as its simplicity, fastness, and use of no hazardous disperser and extraction solvents- OS-AALLME is an enough sensitive and efficient method for the extraction of these dyes from complex matrices. After optimization and validation, OS-AALLME was applied to estimate the concentration of 1-amino-2-naphthol in human bio-fluids as a main reductive metabolite of selected dyes. Levels of 1-amino-2-naphthol in plasma and urinary excretion suggested that this compound may be used as a new potential biomarker of these dyes in human body. PMID:26149246

  10. Development of efficiency improved polymer-modified TiO2 for the photocatalytic degradation of an organic dye from wastewater environment

    NASA Astrophysics Data System (ADS)

    Sangareswari, Murugan; Meenakshi Sundaram, Mariappan

    2015-10-01

    In this study, the photocatalytic activity of polypyrrole-TiO2 nanocomposite was studied experimentally for the degradation of methylene blue (MB) dye under simulating solar light irradiation. To improve the photocatalytic activity of TiO2 under sunlight irradiation, conducting polymers such as polypyrrole (PPy) and its derivatives are generally used as photosensitizers. The PPy-TiO2 nanocomposite was prepared by the chemical oxidative polymerization method. The prepared nanocomposite showed better photocatalytic activity than bare TiO2 under sunlight irradiation for the degradation of MB dye. The prepared nanocomposite was subjected to characterization techniques such as SEM-EDAX, FT-IR, UV-DRS, XRD, TGA and PL spectral analysis. Different influencing operating parameters like initial concentration of dye, irradiation time, pH and amount of PPy-TiO2 nanocomposite used have also been studied. The optical density of the dye degradation was measured by UV-Visible spectrophotometer. The repeatability of photocatalytic activity was also tested. A plausible mechanism was proposed and discussed on the basis of experimental results.

  11. Simple method for the analysis of food dyes on reversed-phase thin-layer plates.

    PubMed

    Oka, H; Ikai, Y; Kawamura, N; Yamada, M; Inoue, H; Ohno, T; Inagaki, K; Kuno, A; Yamamoto, N

    1987-12-18

    A technique for the determination of food dyes using reversed-phase thin-layer chromatography on octadecyl-modified silica is described. A solvent system containing 5.0% aqueous sodium sulphate solution enables good separation of the food dyes. Their separation is dependent on the pH of the solvent system, good separation among all dyes being obtained between pH 6.0 and 7.0. The determination of thirteen dyes can be achieved by a combination of methanol-acetonitrile-5.0% aqueous sodium sulphate solution (3:3:10) (solvent system A) and methanol-methyl ethyl ketone-5.0% aqueous sodium sulphate solution (1:1:1) (solvent system B). Solvent system A was used for the determination of Tartrazine, Amaranth, Indigo Carmine, New Coccine, Sunset Yellow FCF, Allura Red AC, Fast Green FCF and Brilliant Blue FCF and for the screening of Acid Red (R-106), Eosin (R-103), Erythrosin (R-3), Rose Bengale (R-105) and Phloxine (R-104). When the spots of R-3, R-103, R-104, R-105 and R-106 appear on the plate, their determination can be achieved by using solvent system B. Each calibration graph was linear between 0.2 and 1.0 micrograms. PMID:3443633

  12. Seeking effective dyes for a mediated glucose-air alkaline battery/fuel cell

    NASA Astrophysics Data System (ADS)

    Eustis, Ross; Tsang, Tsz Ming; Yang, Brigham; Scott, Daniel; Liaw, Bor Yann

    2014-02-01

    A significant level of power generation from an abiotic, air breathing, mediated reducing sugar-air alkaline battery/fuel cell has been achieved in our laboratories at room temperature without complicated catalysis or membrane separation in the reaction chamber. Our prior studies suggested that mass transport limitation by the mediator is a limiting factor in power generation. New and effective mediators were sought here to improve charge transfer and power density. Forty-five redox dyes were studied to identify if any can facilitate mass transport in alkaline electrolyte solution; namely, by increasing the solubility and mobility of the dye, and the valence charge carried per molecule. Indigo dyes were studied more closely to understand the complexity involved in mass transport. The viability of water-miscible co-solvents was also explored to understand their effect on solubility and mass transport of the dyes. Using a 2.0 mL solution, 20% methanol by volume, with 100 mM indigo carmine, 1.0 M glucose and 2.5 M sodium hydroxide, the glucose-air alkaline battery/fuel cell attained 8 mA cm-2 at short-circuit and 800 ?W cm-2 at the maximum power point. This work shall aid future optimization of mediated charge transfer mechanism in batteries or fuel cells.

  13. Efficiency Records in Mesoscopic Dye-Sensitized Solar Cells.

    PubMed

    Albero, Josep; Atienzar, Pedro; Corma, Avelino; Garcia, Hermenegildo

    2015-08-01

    The aim of the present review article is to show the progress achieved in the efficiency of dye-sensitized solar cells (DSSCs) by evolution in the structure and composition of the dye. After an initial brief description of DSSCs and the operating mechanism the major part of the present article is organized according to the type of dye, trying to show the logic in the variation of the dye structure in order to achieve strong binding on the surface of the layer of nanoparticulate TiO2 , efficient interfacial electron injection between the excited dye and the semiconductor, and minimization of the unwanted dark current processes. Besides metal complexes, including polypyridyls and nitrogenated macro rings, organic dyes and inorganic light harvesters such as quantum dots and perovskites have also been included in the review. The last section summarizes the current state of the art and provides an overview on future developments in the field. PMID:26183911

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

    PubMed

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

    2014-12-28

    A major deficit in suitable dyes is stifling progress in the dye-sensitised solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over two decades ago. Research on these dyes has nevertheless revealed relationships between the molecular structure of dyes and their associated DSC efficiency. Here, such structure-property relationships have been codified in the form of molecular dye design rules, which have been judiciously sequenced in an algorithm to enable large-scale data mining of dye structures with optimal DSC performance. This affords, for the first time, a DSC-specific dye-discovery strategy that predicts new classes of dyes from surveying a representative set of chemical space. A lead material from these predictions is experimentally validated, showing DSC efficiency that is comparable to many well-known organic dyes. This demonstrates the power of this approach. PMID:25011389

  15. Data Mining with Molecular Design Rules Identifies New Class of Dyes for Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Cole, Jacqueline

    2014-03-01

    A major deficit in suitable dyes is stiffling progress in the dye-sensitized solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over two decades ago. Research on these dyes has nevertheless revealed relationships between the molecular structure of dyes and their associated DSC efficiency. Here, we have codified such structure-property relationships in the form of molecular dye design rules, which have been judiciously sequenced in an algorithm to enable large-scale data mining of dye structures with optimal DSC performance. For the first time, we have a DSC-specific dye-discovery strategy that predicts new classes of dyes from surveying a representative set of chemical space. A lead material from these predictions is experimentally validated herein, showing DSC efficiency that is comparable to many well-known organic dyes. This demonstrates the power of this approach.

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

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

  17. 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##

  18. 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.

  19. 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.

  20. Toxicity of xanthene food dyes by inhibition of human drug-metabolizing enzymes in a noncompetitive manner.

    PubMed

    Mizutani, Takaharu

    2009-01-01

    The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC(50) values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC(50) values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of (1)O(2) originating on xanthene dyes by light irradiation, because inhibition was prevented by (1)O(2) quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin. PMID:20041016

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

    PubMed Central

    Mizutani, Takaharu

    2009-01-01

    The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC50 values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of 1O2 originating on xanthene dyes by light irradiation, because inhibition was prevented by 1O2 quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin. PMID:20041016

  2. Decolorization and removal of textile and non-textile dyes from polluted wastewater and dyeing effluent by using potato (Solanum tuberosum) soluble and immobilized polyphenol oxidase.

    PubMed

    Khan, Amjad Ali; Husain, Qayyum

    2007-03-01

    Celite bound potato polyphenol oxidase preparation was employed for the treatment of wastewater/dye effluent contaminated with reactive textile and non-textile dyes, Reactive Blue 4 and Reactive Orange 86. The maximum decolorization was found at pH 3.0 and 4.0 in case of Reactive Blue 4 and Reactive Orange 86, respectively. Immobilized potato polyphenol oxidase was significantly more effective in decolorizing the individual dye and complex mixtures of dyes as compared to soluble enzyme. The absorption spectra of the treated and untreated dye mixture and dyeing effluent exhibited a marked difference in the absorption value at various wavelengths. The polluted water contaminated with an individual dye or mixtures of dyes treated with soluble and immobilized potato polyphenol oxidase resulted in the remarkable loss in total organic carbon. PMID:16765044

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

    NASA Astrophysics Data System (ADS)

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

    2012-05-01

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

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

    NASA Astrophysics Data System (ADS)

    Devi, L. Gomathi; Kumar, S. Girish

    2011-01-01

    To understand the role of dopant inside TiO2 matrix, anatase TiO2 was doped with transition metal ions like Mn2+, Fe3+, Ru3+ and Os3+ having unique half filled electronic configuration and their photocatalytic activity was probed in the degradation of Indigo Carmine (IC) and 4-nitrophenol (NP) under UV/solar light. For comparison, TiO2 was also doped with V5+, Ni2+ and Zn2+ metal ions having d0, d8 and d10 electronic configuration respectively. Irrespective of excitation source UV/solar light and nature of the organic pollutant, photocatalytic activities of doped photocatalysts followed the order: Mn2+-TiO2 > Fe3+-TiO2 > Ru3+-TiO2 ? Os3+-TiO2 > Zn2+-TiO2 > V5+-TiO2 > Ni2+-TiO2 at an optimum concentration of dopant. Based on the experimental results obtained, it is proposed that the existence of dopant with half filled electronic configuration in TiO2 matrix which is known to enhance the photocatalytic activity is not universal! Rather it is a complex function of several physicochemical-electronic properties of doped titania. Enhanced photocatalytic activity of Mn2+ (0.06 at.%)-TiO2 was attributed to the combined factors of high positive reduction potential of Mn2+/Mn3+ pairs, synergistic effects in the mixed polymorphs of anatase and rutile, smaller crystallite size with high intimate contact between two phases and favorable surface structure of the photocatalyst. Despite the intense research devoted to transition metal ion doped TiO2, it is rather difficult to make unifying conclusion which is highlighted in this study.

  5. The Development and Application of Novel IR and NMR-Based Model for the Evaluation of Carminative Effect of Artemisia judaica L. Essential Oil

    PubMed Central

    Alzweiri, Muhammed; Alrawashdeh, Ibrahim M.; Bardaweel, Sanaa K.

    2014-01-01

    Artemisia judaica L. is a medicinal plant that is traditionally used to relieve abdominal pains through its carminative activity. In this study, spectroscopic analysis was employed to investigate the carminative activity associated with A. judaica. Using infrared spectroscopy, the carminative activity was evaluated based on the first derivative of IR-characteristic stretching signal of CO2. Our results indicate that A. judaica oil effectively reduced the response of CO2 signal equivalent to thymol standard. Additionally, 1H-NMR spectroscopy was utilized to assess surface activity of A. judaica crude oil through the reduction of interfacial tension in a D2O/CDCl3 system. Apparently, 10?mg of the oil was able to solubilize water in a chloroform layer up to 4.3% (w/w). In order to correlate the observed surface activity of the oil to its actual composition, GC-MS and GC-FID structural analysis were undertaken. The results revealed that the oil composition consists of oxygenated terpenes which might be responsible for the carminative effect. Furthermore, owing to its sensitivity, our model provides a fundamental basis for the pharmacological assessment of trace amounts of oils with high precision and accuracy. PMID:25614741

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

    EPA Science Inventory

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

  7. Bi-anchoring organic sensitizers of type D-(?-A)2 comprising thiophene-2-acetonitrile as ?-spacer and malonic acid as electron acceptor for dye sensitized solar cell applications

    NASA Astrophysics Data System (ADS)

    Reddy, Gachumale Saritha; Ramkumar, Sekar; Asiri, Abdullah M.; Anandan, Sambandam

    2015-06-01

    Two new bi-anchoring organic sensitizers of type D-(?-A)2 comprising the identical ?-spacer (thiophene-2-acetonitrile) and electron acceptor (malonic acid) but different aryl amine as electron donors (diphenylamine and carbazole) were synthesized, characterized and fabricated metal free dye-sensitized solar cell devices. The intra molecular charge transfer property and electrochemical property of these dyes were investigated by molecular absorption, emission, cyclic voltammetric experiments and in addition, quantum chemical calculation studies were performed to provide sufficient driving force for the electron injection into the conduction band of TiO2 which leads to efficient charge collection. Among the fabricated devices, carbazole based device exhibits high current conversion efficiency (? = 4.7%) with a short circuit current density (JSC) 15.3 mA/cm2, an open circuit photo voltage (VOC) of 0.59 V and a fill factor of 0.44 under AM 1.5 illumination (85 mW/cm2) compared to diphenylamine based device.

  8. Doping nano-Co3O4 surface with bigger nanosized Ag and its photocatalytic properties for visible light photodegradation of organic dyes

    NASA Astrophysics Data System (ADS)

    Chen, Guangliang; Si, Xiaolei; Yu, Jinsong; Bai, Huiyu; Zhang, Xianhui

    2015-03-01

    This paper reports the synthesis of nanosized Ag/Co3O4 composite catalysts using a silver-mirror reaction and the calibration of their catalytic activities towards methyl blue (MB) dye degradation with peroxymonosulfate (PMS) under visible light. The nanosized Ag/Co3O4 composites were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy. The experimental evidence indicated that the hydrothermal synthesis approach lead to the exposure of the {1 1 2} facets of the Co3O4 nanoflakes. Compared to Co3O4 nanoflakes, Co3O4 doped with Ag nanoparticle (average diameters of 10-15 nm) presented lower band gap energy and photoluminescent (PL) intensity. Meanwhile, the Ag/Co3O4 exhibited high stability and excellent dispersion property in dye solution. Experimental data suggested that 3.06 wt% Ag nanoparticle-doped Ag/Co3O4 nanocomposite catalyst possessed the highest catalytic activity towards MB degradation in aqueous solution at the tested concentration level of 15 mg/L, about 2.4 times higher than that of pure Co3O4. Complete decolorization of the 15 mg/L MB solution can be achieved by 3.06 wt% Ag-doped Ag/Co3O4 nanocomposite within 20 min of visible light irradiation.

  9. 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.

  10. A green-chemical synthetic route to fabricate a lamellar-structured Co/Co(OH)2 nanocomposite exhibiting a high removal ability for organic dye.

    PubMed

    Wu, Longyun; Liu, Yuhua; Zhang, Lishu; Zhao, Lijun

    2014-04-14

    A novel lamellar-structured Co/Co(OH)2 nanocomposite was synthesized with a room-temperature solution-phase reduction method. A possible reaction mechanism and shape evolutionary process for the Co/Co(OH)2 nanocomposite were supposed. The Co/Co(OH)2 nanocomposite shows a ferromagnetic behavior. Congo red (CR) was used to evaluate the Co/Co(OH)2 nanocomposite wastewater treatment capability. It was found that 150 ppm of CR could be removed from an aqueous solution within 10 min using the Co/Co(OH)2 nanocomposite, and the adsorption maximum is 2058 mg g(-1) which is higher than all previously reported values. The significantly reduced treatment time required to remove the CR and the simple, low-cost and pollution-free preparation method make the Co/Co(OH)2 nanocomposite promising for use in the highly efficient removal of dyes from wastewater. PMID:24519445

  11. Electron transfer mediation by aqueous C60 aggregates in H2O2/UV advanced oxidation of indigo carmine

    NASA Astrophysics Data System (ADS)

    Ge, Ling; Moor, Kyle; Zhang, Bo; He, Yiliang; Kim, Jae-Hong

    2014-10-01

    C60 fullerene has long been known to exhibit favorable electron accepting and shuttling properties, but little is known about the possibility of electron transfer mediation by fullerene aggregates (nC60) in water. In this study, we investigated the electron shuttling capabilities of nC60 using UV/H2O2 as a model oxidation process in the presence of an electron donor, indigo carmine (IC). nC60 addition to the IC/H2O2 system was found to drastically increase IC degradation and shift the reactive oxygen species (ROS) balance, favoring the formation of superoxide and perhydroxyl radical species compared to hydroxyl radicals. Results indicate that nC60 can act as an electron mediator, where the adsorbed IC donates an electron to nC60, which is subsequently transferred to H2O2 or perhydroxyl radical.C60 fullerene has long been known to exhibit favorable electron accepting and shuttling properties, but little is known about the possibility of electron transfer mediation by fullerene aggregates (nC60) in water. In this study, we investigated the electron shuttling capabilities of nC60 using UV/H2O2 as a model oxidation process in the presence of an electron donor, indigo carmine (IC). nC60 addition to the IC/H2O2 system was found to drastically increase IC degradation and shift the reactive oxygen species (ROS) balance, favoring the formation of superoxide and perhydroxyl radical species compared to hydroxyl radicals. Results indicate that nC60 can act as an electron mediator, where the adsorbed IC donates an electron to nC60, which is subsequently transferred to H2O2 or perhydroxyl radical. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr03647f

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

    NASA Astrophysics Data System (ADS)

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

    2011-09-01

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

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

    SciTech Connect

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

    2011-09-22

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

  14. Degradation of environment pollutant dyes using phytosynthesized metal nanocatalysts

    NASA Astrophysics Data System (ADS)

    MeenaKumari, M.; Philip, Daizy

    2015-01-01

    We present for the first time biogenic reduction and stabilization of gold and silver ions at room temperature using fruit juice of Punica granatum. The formation, morphology and crystalline structure of the synthesized nanoparticles are determined using UV-Visible, XRD and TEM. An attempt to reveal the partial role of phenolic hydroxyls in the reduction of Au3+ and Ag+ is done through FTIR analysis. The synthesized nanoparticles are used as potential catalysts in the degradation of a cationic phenothiazine dye, an anionic mono azo dye and a cationic fluorescent dye. The calculated values of percentage removal of dyes and the rate constants from pseudo first order kinetic data fit give a comparative study on degradation of organic dyes in presence of prepared gold and silver nanoparticles.

  15. Comparative performance evaluation of Aspergillus lentulus for dye removal through bioaccumulation and biosorption.

    PubMed

    Kaushik, Prachi; Malik, Anushree

    2013-05-01

    Dyes used in various industries are discharged into the environment and pose major environmental concern. In the present study, fungal isolate Aspergillus lentulus was utilized for the treatment of various dyes, dye mixtures and dye containing effluent in dual modes, bioaccumulation (employing growing biomass) and biosorption (employing pre-cultivated biomass). The effect of dye toxicity on the growth of the fungal isolate was studied through phase contrast and scanning electron microscopy. Dye biosorption was studied using first and second-order kinetic models. Effects of factors influencing adsorption and isotherm studies were also conducted. During bioaccumulation, good removal was obtained for anionic dyes (100 mg/l), viz. Acid Navy Blue, Fast Red A and Orange-HF dye (99.4 %, 98.8 % and 98.7 %, respectively) in 48 h. Cationic dyes (10 mg/l), viz. Rhodamine B and Methylene Blue, had low removal efficiency (80.3 % [48 h] and 92.7 % [144 h], respectively) as compared to anionic dyes. In addition to this, fungal isolate showed toxicity response towards Methylene Blue by producing larger aggregates of fungal pellets. To overcome the limitations of bioaccumulation, dye removal in biosorption mode was studied. In this mode, significant removal was observed for anionic (96.7-94.3 %) and cationic (35.4-90.9 %) dyes in 24 h. The removal of three anionic dyes and Rhodamine B followed first-order kinetic model whereas removal of Methylene Blue followed second-order kinetic model. Overall, fungal isolate could remove more than 90 % dye from different dye mixtures in bioaccumulation mode and more than 70 % dye in biosorption mode. Moreover, significant color removal from handmade paper unit effluent in bioaccumulation mode (86.4 %) as well as in biosorption mode (77.1 %) was obtained within 24 h. This study validates the potential of fungal isolate, A. lentulus, to be used as the primary organism for treating dye containing wastewater. PMID:22996821

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

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

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

  17. 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.

  18. 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.

  19. Hair Dyes and Cancer Risk

    MedlinePLUS

    ... 1331. [PubMed Abstract] Rauscher GH, Shore D, Sandler DP. Hair dye use and risk of adult acute ... 10):1448–1454. [PubMed Abstract] Lin J, Dinney CP, Grossman HB, Wu X. Personal permanent hair dye ...

  20. One-pot synthesis of C??-functionalized core-shell magnetic mesoporous silica composite as efficient sorbent for organic dye.

    PubMed

    Zhang, Xiaole; Zeng, Tao; Wang, Saihua; Niu, Hongyun; Wang, Xiaoke; Cai, Yaqi

    2015-06-15

    In this work, a facile one-pot strategy was proposed for the synthesis of C18-functionalized core-shell magnetic mesoporous silica composite (Fe3O4/mSiO2-C18). The Fe3O4/mSiO2-C18 composite, with an average size of 80 nm and a functionalized mesoporous silica shell of about 30 nm in thickness, has excellent adsorption ability toward methylene blue dye (MB) due to the large surface area (303 m(2) g(-1)) and the abundant hydrophobic C18 groups. The adsorption equilibrium was achieved within 20 min and the adsorption behavior of MB on Fe3O4/mSiO2-C18 composite fitted the pseudo-second-order kinetic model well (k2=1.29×10(-2) g mg(-1) min(-1), q(e)=144.72 mg g(-1), h(o)=270.27 mg g(-1) min(-1) under 25 °C and an initial MB concentration of 10 mg L(-1)). Langmuir and Freundlich isothermal adsorption models can both be used to describe the adsorption process and the maximum Langmuir adsorption capacity of MB on Fe3O4/mSiO2-C18 at 25 °C and pH 7.5 is 363.64 mg g(-1). Thermodynamic parameters show that the adsorption reaction is exothermic and spontaneous (?H(0)=-63.49 kJ mol(-1), ?G(0)=-7.80 kJ mol(-1)). Ionic strength and pH affected the adsorption slightly. In addition, the MB adsorbed sorbent can be readily separated from water solution by an external magnet because of the high magnetic saturation value (22.62 emu g(-1)). After being regenerated by treatment with acidic methanol, the sorbent could be reused for at least 5 cycles with a little decrease in adsorption capacity. PMID:25734221

  1. Electrochemical removal of synthetic textile dyes from aqueous solutions using Ti/Pt anode: role of dye structure.

    PubMed

    Araújo, Cynthia K C; Oliveira, Gustavo R; Fernandes, Nedja S; Zanta, Carmem L P S; Castro, Suely Souza Leal; da Silva, Djalma R; Martínez-Huitle, Carlos A

    2014-01-01

    In this work, the efficiency of electrochemical oxidation (EO) was investigated for removing a dye mixture containing Novacron Yellow (NY) and Remazol Red (RR) in aqueous solutions using platinum supported on titanium (Ti/Pt) as anode. Different current densities (20, 40 and 60 mA cm(-2)) and temperatures (25, 40 and 60 °C) were studied during electrochemical treatment. After that, the EO of each of these dyes was separately investigated. The EO of each of these dyes was performed, varying only the current density and keeping the same temperature (25 °C). The elimination of colour was monitored by UV-visible spectroscopy, and the degradation of organic compounds was analysed by means of chemical oxygen demand (COD). Data obtained from the analysis of the dye mixture showed that the EO process was effective in colour removal, in which more than 90% was removed. In the case of COD removal, the application of a current density greater than 40 mA cm(-2) favoured the oxygen evolution reaction, and no complete oxidation was achieved. Regarding the analysis of individual anodic oxidation dyes, it was appreciated that the data for the NY were very close to the results obtained for the oxidation of the dye mixture while the RR dye achieved higher colour removal but lower COD elimination. These results suggest that the oxidation efficiency is dependent on the nature of the organic molecule, and it was confirmed by the intermediates identified. PMID:24801286

  2. A metal-free N-annulated thienocyclopentaperylene dye: power conversion efficiency of 12% for dye-sensitized solar cells.

    PubMed

    Yao, Zhaoyang; Zhang, Min; Li, Renzhi; Yang, Lin; Qiao, Yongna; Wang, Peng

    2015-05-11

    Reported are two highly efficient metal-free perylene dyes featuring N-annulated thienobenzoperylene (NTBP) and N-annulated thienocyclopentaperylene (NTCP), which are coplanar polycyclic aromatic hydrocarbons. Without the use of any coadsorbate, the metal-free organic dye derived from the NTCP segment was used for a dye-sensitized solar cell which attained a power conversion efficiency of 12% under an irradiance of 100?mW?cm(-2), simulated air mass global (AM1.5G) sunlight. PMID:25820975

  3. Planar amine-based dye features the rigidified O-bridged dithiophene ?-spacer: A potential high-efficiency sensitizer for dye-sensitized solar cells application

    NASA Astrophysics Data System (ADS)

    Li, Wei; Bai, Fu-Quan; Chen, Jie; Wang, Jian; Zhang, Hong-Xing

    2015-02-01

    This work reports a systematically theoretical study concerning the design of D-?-A organic dyes for DSSC. Two elaborate strategies, namely the rigidity of dithiophene and introduction of strong electron rich/deficient moieties, are proposed. By using the state-of-the-art theoretical calculations, the general influences of fastening atoms (C, N, and O) for ?-spacer rigidification in planar amine-based organic dyes are firstly investigated and elucidated. The properties of isolated dye, dye/(TiO2)38, and dye-I2 interaction are discussed in detail. The results show that, compared with the P2T dye containing dithiophene ?-spacer, its three counterparts with rigidified dithiophene ?-spacers would present the improved absorption properties. We further demonstrate that incorporation of O-bridged dithiophene moiety into the ?-spacer was promising to challenge the photoelectric conversion efficiency 8.29% of P2T. Furthermore, benzothiadiazole (BTD) and 3,4-ethylenedioxythiophene (EDOT) moieties are the well-known ?-skeletons that can effectively tune the electronic structure properties and the light-harvesting ability. Subsequently, a series of dyes are designed through introducing the BTD and EDOT groups into ?-spacer. The calculated results reveal that the dye with the incorporation of EDOT moiety would be more beneficial for photocurrent and photovoltage performance. The current theoretical studies are expected to be very relevant for the molecular design of D-?-A organic dyes in DSSC.

  4. Pigment violet 19 - a test case to define a simple method to simulate the vibronic structure of absorption spectra of organic pigments and dyes in solution.

    PubMed

    Champagne, Benoît; Liégeois, Vincent; Zutterman, Freddy

    2015-02-01

    A typical quinacridone pigment, PV19, has been used to analyze the impact of several computational parameters on the UV/vis absorption band shape in solution, simulated using density functional theory and time-dependent density functional theory levels of approximation. These encompass, (i) the choice of exchange-correlation functional, (ii) the basis set, (iii) the method for non-equilibrium optimization of the excited state geometry, (iv) the approach for evaluating the vibronic band structure, (v) the peak broadening, and (vi) the scaling of the harmonic vibrational frequencies. Among these, the choice of exchange-correlation functional is certainly of the most importance because it can drastically modify the spectral shape. In the case of PV19, the M05-2X and to a lesser extent CAM-B3LYP XC functionals are the most efficient to reproduce the vibronic structure, confirming the important role of exact Hartree-Fock exchange. Still, these functionals are not the most reliable to predict the excitation energies and oscillator strengths, for which M05, a functional with less HF exchange, performs better. For evaluating the vibronic structure, the simple gradient method, where only one step of geometry optimization of the excited state is carried out and the gradients are used to evaluate the Huang-Rhys factors as well as to determine the excited state geometries produces a spectrum that is very similar to the ones obtained with the more involved Duschinsky and geometry methods, opening the way to a fast simulation of the UV/vis absorption spectra of pigments and dyes. Then, the effect of scaling the calculated vibrational frequencies to account for anharmonicity effects as well as for limitation of the method also impacts the shape of the vibronic spectrum and this effect depends on the method used to determine the Huang-Rhys factors. Indeed, scaling the vibrational frequencies by a factor which is typically smaller than 1.0 results in a relative decrease of the 0-1 peak intensity with respect to the 0-0 band when optimizing the geometry of the excited state whereas the effect is opposite and magnified if using the gradient method. PMID:25501947

  5. Alzheimer's Dye Test?

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Massachusetts Institute of Technology (MIT) scientists have developed a new dye that could offer noninvasive early diagnosis of Alzheimer's disease, a discovery that could aid in monitoring the progression of the disease and in studying the efficacy of new treatments to stop it. The work is published in Angewandte Chemie. Today, doctors can only…

  6. Indanthrone dye revisited after sixty years.

    PubMed

    Kotwica, Kamil; Bujak, Piotr; Wamil, Damian; Materna, Mariusz; Skorka, Lukasz; Gunka, Piotr A; Nowakowski, Robert; Golec, Barbara; Luszczynska, Beata; Zagorska, Malgorzata; Pron, Adam

    2014-10-01

    Indanthrone, an old, insoluble dye can be converted into a solution processable, self-assembling and electroluminescent organic semiconductor, namely tetraoctyloxydinaptho[2,3-a:2',3'-h]phenazine (P-C8), in a simple one-pot process consisting of the reduction of the carbonyl group by sodium dithionite followed by the substitution with solubility inducing groups under phase transfer catalysis conditions. PMID:25133516

  7. The Comparative Nucleophilicity of Naphthoxide Derivatives in Reactions with a Fast-Red TR Dye: A Discovery-Oriented Capstone Project for the Second-Year Organic Laboratory

    ERIC Educational Resources Information Center

    Mascarenhas, Cheryl M.

    2008-01-01

    In this experiment, organic chemistry students perform reactions between three naphthyl acetate derivatives and the diazonium salt Fast-Red TR, under basic conditions. The three naphthyl acetate derivatives used in this study are 2-naphthyl acetate (1a), 6-bromo-2-naphthyl acetate (1b) and 1,6-dibromo-2-naphthyl acetate (1c). The two-step, one-pot…

  8. Modulation of Electron Injection Dynamics of Ru-Based Dye/TiO2 System in the Presence of Three Different Organic Solvents: Role of Solvent Dipole Moment and Donor Number.

    PubMed

    Mahanta, Subrata; Matsuzaki, Hiroyuki; Murakami, Takurou N; Katoh, Ryuzi; Matsumoto, Hajime; Furube, Akihiro

    2015-06-01

    In the present work, femtosecond transient absorption spectroscopy (fs-TAS) has been employed to investigate the electron injection efficiency (EIE) both from the singlet and triplet excited states of a well-known ruthenium dye (N719) to the conduction band (CB) of nanostructured TiO(2) in presence of three different organic solvents [?-butylactone (GBL), 3-methoxypropionitrile (MPN), and dimethylformamide (DMF)] with different donor numbers (DNs) and dipole moments (DMs). The DM and DN of a solvent modulates the CB edge energy of TiO(2), and this effect reflects well in the fs-TAS results, which shows an EIE trend following the order GBL?MPN?DMF, that is, highest in GBL and lowest in DMF solvent environments. Fs-TAS results indicate a lower contribution of electron injection from both the singlet and triplet states in DMF, for which the dominant adsorption of DMF molecules on the TiO(2) surface seems to play an important role in the mechanism. PMID:25832779

  9. Enhancement of the photoproperties of solid-state TiO2|dye|CuI cells by coupling of two dyes

    NASA Astrophysics Data System (ADS)

    Sirimanne, P. M.; Senevirathna, M. K. I.; Premalal, E. V. A.; Pitigala, P. K. D. D. P.

    2006-06-01

    The electronic coupling of a natural pigment extracted from pomegranate fruits (rich with cyanin and exist as flavylium at natural PH) with an organic dye mercurochrome enhanced the performance of solid-state TiO2|dye|CuI-type photovoltaic cells sensitized from pomegranate pigments or mercurochrome individually.

  10. Substituent effects on the croconate dyes in dye sensitized solar cell applications: a density functional theory study.

    PubMed

    Chitumalla, Ramesh Kumar; Lim, Manho; Gao, Xingfa; Jang, Joonkyung

    2015-11-01

    Using the density functional theory (DFT), we studied two model croconate dyes, one with an electron-donating substituent (CR1) and the other with an electron-withdrawing group (CR2). The geometric, electronic, and optical properties of these dyes were compared. Upon switching from CR1 to CR2, a considerable bathochromic shift was observed in the electronic absorption spectrum. We also investigated the adsorption behavior of the two dyes on a TiO2 (101) anatase surface by employing periodic DFT simulations. The periodic electronic-structure calculations revealed that the diketo group of CR1 bound more strongly to the TiO2 surface than that of CR2, with a binding strength comparable to that of a typical organic D-?-A dye. In this work we evaluate in particular the effect of the electron withdrawing/donating nature of the substituent on the electronic, optical, and adsorption properties of the croconate dyes. Finally, we hope that the present study will help in the design of highly efficient dyes for dye sensitized solar cells by considering substituent effects. Graphical abstract Effect of substituent on binding energy and charge transfer. PMID:26518689

  11. Dyeing fabrics with metals

    NASA Astrophysics Data System (ADS)

    Kalivas, Georgia

    2002-06-01

    Traditionally, in textile dyeing, metals have been used as mordants or to improve the color produced by a natural or synthetic dye. In biomedical research and clinical diagnostics gold colloids are used as sensitive signals to detect the presence of pathogens. It has been observed that when metals are finely divided, a distinct color may result that is different from the color of the metal in bulk. For example, when gold is finely divided it may appear black, ruby or purple. This can be seen in biomedical research when gold colloids are reduced to micro-particles. Bright color signals are produced by few nanometer-sized particles. Dr. William Todd, a researcher in the Department of Veterinary Science at the Louisiana State University, developed a method of dyeing fabrics with metals. By using a reagent to bond the metal particles deep into the textile fibers and actually making the metal a part of the chemistry of the fiber. The chemicals of the fabric influence the resulting color. The combination of the element itself, the size of the particle, the chemical nature of the particle and the interaction of the metal with the chemistry of the fabric determine the actual hue. By using different elements, reagents, textiles and solvents a broad range of reproducible colors and tones can be created. Metals can also be combined into alloys, which will produce a variety of colors. The students of the ISCC chapter at the Fashion Institute of Technology dyed fabric using Dr. Todd's method and created a presentation of the results. They also did a demonstration of dyeing fabrics with metals.

  12. Dye-coated europium monosulfide

    SciTech Connect

    Kar, Srotoswini; Dollahon, Norman R.; Stoll, Sarah L.

    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.

  13. Fluorescence properties of organic dyes: quantum chemical studies on the green/blue neutral and protonated DMA-DPH emitters in polymer matrices.

    PubMed

    Kerkines, Ioannis S K; Petsalakis, Ioannis D; Argitis, Panagiotis; Theodorakopoulos, Giannoula

    2011-12-28

    The absorption and fluorescence spectra of the green emitter DMA-DPH {1-[4-(dimethylamino)phenyl]-6-phenylhexa-1,3,5-triene} and its protonated blue-emitter form have been studied theoretically through time-dependent density functional theory (TD-DFT) and resolution-of-identity 2nd order perturbative coupled cluster (RI-CC2) calculations with basis sets up to augmented triple-? quality, in the gas phase and in solvents of different polarity. These systems dispersed in a polymer matrix are of interest for applications in organic light emitting diode devices (OLEDs). Calculations show that the observed absorption and emission spectra correspond to transitions between the S(0) and S(1) states, in both systems. The nature and characteristics of these transitions are discussed. Excellent agreement with experimental data is obtained, both for absorption and emission, provided that the state-specific polarized continuum model (SS-PCM) method is employed for the inclusion of the solvent. PMID:22025129

  14. Improved photocatalytic activity of CdSe-nanocomposites: effect of Montmorillonite support towards efficient removal of Indigo Carmine.

    PubMed

    Chikate, Rajeev C; Kadu, Brijesh S

    2014-04-24

    To ascertain the contribution of adsorptive capacity of Montmorillonite (MMT) towards photocatalytic process, CdSe-MMT nanocomposites are explored for adsorptive removal of Indigo Carmine (IC). The nanocomposites are prepared via two approaches: (a) in-situ formation and (b) wet impregnation of CdSe onto MMT support. XRD analysis of composites suggested the proper dispersion of CdSe nanoparticles in MMT clay matrix with spherical morphology of 5-10nm sized CdSe nanoparticles. These nanocomposites are employed for photocatalytic degradation of IC under visible light at various IC concentrations and different amount of catalyst. Kinetics of IC is found to be of pseudo-second order with 10% in-situ and 50% loaded nanocomposites exhibiting better photocatalytic activity at 1.0 g L(-)(1) catalyst and 100 mg L(-)(1)of IC. Dynamics of its adsorptive removal on the composite surface evaluated by employing error estimation tools clearly suggest that Redlich-Peterson and Flory-Huggins adsorption isotherms effectively describe the multi-layer process. It is observed that spontaneous, exothermic chemisorption process occurring on the surface indeed enhances photocatalytic activity. Moreover, such a feature is also found to be associated with diffusion of IC within mesoporous structure of MMT that subsequently favors pore-diffusion controlled adsorption process. IR spectral analysis demonstrated that IC molecule is degraded on the catalyst surface. Light or oxygenated species induced photocorrosion of CdSe is suppressed due to its composite formation with MMT that results in 620 ppm removal of IC during successive cycles; a feature ascribed as improved photocatalytic activity for CdSe nanoparticles. PMID:24468986

  15. The Chemistry of Plant and Animal Dyes.

    ERIC Educational Resources Information Center

    Sequin-Frey, Margareta

    1981-01-01

    Provides a brief history of natural dyes. Chemical formulas are provided for flavonoids, luteolin, genistein, brazilin, tannins, terpenes, naphthoquinone, anthraquinone, and dyes with an alkaloid structure. Also discusses chemical background of different dye processes. (CS)

  16. Compact dye laser on a chip fabricated by ultraviolet nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Peroz, Ch.; Galas, J.-C.; Le Gratiet, L.; Chen, Y.; Shi, J.

    2006-12-01

    High aspect ratio and high resolution distributed feed back (DFB) gratings have been patterned on a fused silica plate by ultraviolet nanoimprint lithography and reactive ion etch techniques. Then, they were integrated into a microfluidic chip for optofluidic operations. The authors observed laser emission from organic dye solutions flowing through an optical resonator formed between two third order DFB gratings. Such a dye layer can operate with a picoliter dye solution. With rhodamine 6G dye molecules dissolved in ethanol and pumped by a frequency-doubled Nd:YAG pulsed laser, a laser emission of threshold of 12?J/mm2 has been found.

  17. 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

  18. Triphenylamine-based indoline derivatives for dye-sensitized solar cells: a density functional theory investigation.

    PubMed

    Ren, Xue-Feng; Kang, Guo-Jun; He, Qiong-Qiong

    2016-01-01

    A new series of triphenylamine-based indoline dye sensitizers were molecularly designed and investigated for their potential use in dye-sensitized solar cells (DSSCs). Theoretical calculations revealed that modifying donor part of D149 by triphenylamine significantly altered the electronic structures, MO energies, and intramolecular chargetransfer (ICT) absorption band. Key parameters associated with the light-harvesting efficiency at a given wavelength LHE(?), the driving force ?G inject, and the open-circuit photovoltage V oc were characterized. More importantly, these designed (dimeric) dye sensitizers were found to have similar broad absorption spectra to their corresponding monomers, indicating that modifying the donor part with triphenylamine may stop unfavorable dye aggregation. Further analyses of the dye-(TiO2)9 cluster interaction confirmed that there was strong electronic coupling at the interface. These results are expected to provide useful guidance in the molecular design of new highly efficient metal-free organic dyes. PMID:26659403

  19. New triarylamine sensitizers for high efficiency dye-sensitized solar cells: Recombination kinetics of cobalt(III) complexes at titania/dye interface

    NASA Astrophysics Data System (ADS)

    Gao, Weixue; Liang, Mao; Tan, Yulin; Wang, Min; Sun, Zhe; Xue, Song

    2015-06-01

    A new generation of dye-sensitized solar cells (DSCs) is based on a combination of D-?-A organic dyes in conjunction with cobalt-based redox mediators. Here, two new triarylamine organic dyes (M36 and M37) toward cobalt electrolytes are constructed and employed as photosensitizers for dye-sensitized solar cells. The photoelectrochemical properties and photovoltaic performance of dyes are sensitive to the slightly structural modification of the terminal donor in triarylamine. Recombination kinetics of cobalt(III) complexes at titania/dye interface are also studied using electrochemical impedance spectroscopy and controlled intensity modulated photovoltage spectroscopy measurements. Our results show that, for M36 sensitized DSCs, a Marcus inverted region can be reached for the charge recombination kinetics behavior of cobalt(III) species. While that for DSCs based on M37 just lies in the Marcus normal region. The results can be attributed to differences in the retarding charge recombination ability of the dye layer. Benefiting from a Marcus inverted region behavior, the M36 dye exhibits a good compatibility with the [Co(phen)3]2+/3+ redox couples, achieving a high overall power conversion efficiency (PCE) of 9.58% under full sun illumination.

  20. 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.

  1. 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.

  2. Recent Advances in Heterogeneous Photocatalytic Decolorization of Synthetic Dyes

    PubMed Central

    Muhd Julkapli, Nurhidayatullaili; Bagheri, Samira; Bee Abd Hamid, Sharifah

    2014-01-01

    During the process and operation of the dyes, the wastes produced were commonly found to contain organic and inorganic impurities leading to risks in the ecosystem and biodiversity with the resultant impact on the environment. Improper effluent disposal in aqueous ecosystems leads to reduction of sunlight penetration which in turn diminishes photosynthetic activity, resulting in acute toxic effects on the aquatic flora/fauna and dissolved oxygen concentration. Recently, photodegradation of various synthetic dyes has been studied in terms of their absorbance and the reduction of oxygen content by changes in the concentration of the dye. The advantages that make photocatalytic techniques superior to traditional methods are the ability to remove contaminates in the range of ppb, no generation of polycyclic compounds, higher speed, and lower cost. Semiconductor metal oxides, typically TiO2, ZnO, SnO, NiO, Cu2O, Fe3O4, and also CdS have been utilized as photocatalyst for their nontoxic nature, high photosensitivity, wide band gap and high stability. Various process parameters like photocatalyst dose, pH and initial dye concentrations have been varied and highlighted. Research focused on surface modification of semiconductors and mixed oxide semiconductors by doping them with noble metals (Pt, Pd, Au, and Ag) and organic matter (C, N, Cl, and F) showed enhanced dye degradation compared to corresponding native semiconductors. This paper reviews recent advances in heterogeneous photocatalytic decolorization for the removal of synthetic dyes from water and wastewater. Thus, the main core highlighted in this paper is the critical selection of semiconductors for photocatalysis based on the chemical, physical, and selective nature of the poisoning dyes. PMID:25054183

  3. Recent advances in heterogeneous photocatalytic decolorization of synthetic dyes.

    PubMed

    Muhd Julkapli, Nurhidayatullaili; Bagheri, Samira; Bee Abd Hamid, Sharifah

    2014-01-01

    During the process and operation of the dyes, the wastes produced were commonly found to contain organic and inorganic impurities leading to risks in the ecosystem and biodiversity with the resultant impact on the environment. Improper effluent disposal in aqueous ecosystems leads to reduction of sunlight penetration which in turn diminishes photosynthetic activity, resulting in acute toxic effects on the aquatic flora/fauna and dissolved oxygen concentration. Recently, photodegradation of various synthetic dyes has been studied in terms of their absorbance and the reduction of oxygen content by changes in the concentration of the dye. The advantages that make photocatalytic techniques superior to traditional methods are the ability to remove contaminates in the range of ppb, no generation of polycyclic compounds, higher speed, and lower cost. Semiconductor metal oxides, typically TiO2, ZnO, SnO, NiO, Cu2O, Fe3O4, and also CdS have been utilized as photocatalyst for their nontoxic nature, high photosensitivity, wide band gap and high stability. Various process parameters like photocatalyst dose, pH and initial dye concentrations have been varied and highlighted. Research focused on surface modification of semiconductors and mixed oxide semiconductors by doping them with noble metals (Pt, Pd, Au, and Ag) and organic matter (C, N, Cl, and F) showed enhanced dye degradation compared to corresponding native semiconductors. This paper reviews recent advances in heterogeneous photocatalytic decolorization for the removal of synthetic dyes from water and wastewater. Thus, the main core highlighted in this paper is the critical selection of semiconductors for photocatalysis based on the chemical, physical, and selective nature of the poisoning dyes. PMID:25054183

  4. Preparation of Graphene Oxide-Based Hydrogels as Efficient Dye Adsorbents for Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Guo, Haiying; Jiao, Tifeng; Zhang, Qingrui; Guo, Wenfeng; Peng, Qiuming; Yan, Xuehai

    2015-06-01

    Graphene oxide (GO) sheets exhibit superior adsorption capacity for removing organic dye pollutants from an aqueous environment. In this paper, the facile preparation of GO/polyethylenimine (PEI) hydrogels as efficient dye adsorbents has been reported. The GO/PEI hydrogels were achieved through both hydrogen bonding and electrostatic interactions between amine-rich PEI and GO sheets. For both methylene blue (MB) and rhodamine B (RhB), the as-prepared hydrogels exhibit removal rates within about 4 h in accordance with the pseudo-second-order model. The dye adsorption capacity of the hydrogel is mainly attributed to the GO sheets, whereas the PEI was incorporated to facilitate the gelation process of GO sheets. More importantly, the dye-adsorbed hydrogels can be conveniently separated from an aqueous environment, suggesting potential large-scale applications of the GO-based hydrogels for organic dye removal and wastewater treatment.

  5. Preparation of Graphene Oxide-Based Hydrogels as Efficient Dye Adsorbents for Wastewater Treatment.

    PubMed

    Guo, Haiying; Jiao, Tifeng; Zhang, Qingrui; Guo, Wenfeng; Peng, Qiuming; Yan, Xuehai

    2015-12-01

    Graphene oxide (GO) sheets exhibit superior adsorption capacity for removing organic dye pollutants from an aqueous environment. In this paper, the facile preparation of GO/polyethylenimine (PEI) hydrogels as efficient dye adsorbents has been reported. The GO/PEI hydrogels were achieved through both hydrogen bonding and electrostatic interactions between amine-rich PEI and GO sheets. For both methylene blue (MB) and rhodamine B (RhB), the as-prepared hydrogels exhibit removal rates within about 4 h in accordance with the pseudo-second-order model. The dye adsorption capacity of the hydrogel is mainly attributed to the GO sheets, whereas the PEI was incorporated to facilitate the gelation process of GO sheets. More importantly, the dye-adsorbed hydrogels can be conveniently separated from an aqueous environment, suggesting potential large-scale applications of the GO-based hydrogels for organic dye removal and wastewater treatment. PMID:26123269

  6. 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.

  7. 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.

  8. 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.

  9. Fluorescence properties of dye doped mesoporous silica

    SciTech Connect

    Carbonaro, Carlo M. Corpino, Riccardo Ricci, Pier Carlo Chiriu, Daniele; Cannas, Carla

    2014-10-21

    In this paper we present a review of the main results we obtained studying the emission properties of organic-inorganic hybrids obtained combining mesoporous silica and Xantene dyes, in particular the standard reference Rhodamine 6G. The purpose of the review is to show the possibility to efficiently 'dope' the transparent inorganic porous matrix to obtain promising systems for photonic and biomedical applications. The strategies to solve the concentration effect and the leaching phenomenon are discussed within the framework of the single exciton theory.

  10. Convenient Microscale Synthesis of a Coumarin Laser Dye Analog

    ERIC Educational Resources Information Center

    Aktoudianakis, Evangelos; Dicks, Andrew P.

    2006-01-01

    Coumarin (2H-1-benzopyran-2-one) and its derivatives constitute a fascinating class of organic substances that are utilized industrially in areas such as cosmetics, food preservatives, insecticides and fluorescent laser dyes. The product can be synthesized, purified, and characterized within two hours with benefits of microscale reactivity being…

  11. Microfluidic dye laser intracavity absorption

    NASA Astrophysics Data System (ADS)

    Galas, J. C.; Peroz, C.; Kou, Q.; Chen, Y.

    2006-11-01

    The authors report absorption measurements on low concentration analytes using a microfluidic dye laser. The laser cavity is made of two gold mirrors coated on the end faces of two optical fibers inserted in a chip. Rhodamine 6G dye molecules dissolved in ethanol are used for laser amplification and absorption measurements are done with methylene blue dye solutions. When optically pumped with a frequency doubled Nd:YAG laser at 532nm wavelength, the device shows a laser output emission at 565nm and a high sensitivity of the lasing output to the losses in the cavity, in good agreement with the results of numerical calculations.

  12. Bichromophoric Dyes for Wavelength Shifting of Dye-Protein Fluoromodules

    PubMed Central

    Pham, Ha H.; Szent-Gyorgyi, Christopher; Brotherton, Wendy L.; Schmidt, Brigitte F.; Zanotti, Kimberly J.; Waggoner, Alan S.

    2015-01-01

    Dye-protein fluoromodules consist of fluorogenic dyes and single chain antibody fragments that form brightly fluorescent noncovalent complexes. This report describes two new bichromophoric dyes that extend the range of wavelengths of excitation or emission of existing fluoromodules. In one case, a fluorogenic thiazole orange (TO) was attached to an energy acceptor dye, Cy5. Upon binding to a protein that recognizes TO, red emission due to efficient energy transfer from TO to Cy5 replaces the green emission observed for monochromophoric TO bound to the same protein. Separately, TO was attached to a coumarin that serves as an energy donor. The same green emission is observed for coumarin-TO and TO bound to a protein, but efficient energy transfer allows violet excitation of coumarin-TO, versus longer wavelength, blue excitation of monochromophoric TO. Both bichromophores exhibit low nanomolar KD values for their respective proteins, >95% energy transfer efficiency and high fluorescence quantum yields. PMID:25679477

  13. 2H-[1,2,3]Triazolo[4,5-c]pyridine Cored Organic Dyes Achieving a High Efficiency: a Systematic Study of the Effect of Different Donors and ? Spacers.

    PubMed

    Chaurasia, Sumit; Ni, Jen-Shyang; Hung, Wei-I; Lin, Jiann T

    2015-10-01

    New D-A-?-A-based isomeric sensitizers, PTNn (n = 1-2) and NPTn (n = 1-5), were synthesized using 2H-[1,2,3]triazolo[4,5-c]pyridine (PT) as an auxiliary acceptor, triphenylamine or N,N-bis[4-(hexyloxy)phenyl]aniline as the donor, furan, thiophene, phenyl, or 3-hexylthiophene as the conjugated spacer, and 2-cyanoacrylic acid as the acceptor and anchor as well. They were used as the sensitizers of dye-sensitized solar cells. The NPTn dyes show better performance than the PTNn dyes. Among them, the best efficiency of 7.92% (?96%, N719) was obtained with the NPT5 dye, indicating that the PT core could be used as a new building block for the design of high-performance sensitizers in the future. The negative Mulliken charge from the auxiliary acceptor was found to be useful as a semiempirical index for correlation of the molecular structure with the cell efficiency among structurally similar D-A-?-A-type congeners. PMID:26366610

  14. Decolorization and detoxification of textile dyes with a laccase from Trametes hirsuta.

    PubMed

    Abadulla, E; Tzanov, T; Costa, S; Robra, K H; Cavaco-Paulo, A; Gübitz, G M

    2000-08-01

    Trametes hirsuta and a purified laccase from this organism were able to degrade triarylmethane, indigoid, azo, and anthraquinonic dyes. Initial decolorization velocities depended on the substituents on the phenolic rings of the dyes. Immobilization of the T. hirsuta laccase on alumina enhanced the thermal stabilities of the enzyme and its tolerance against some enzyme inhibitors, such as halides, copper chelators, and dyeing additives. The laccase lost 50% of its activity at 50 mM NaCl while the 50% inhibitory concentration (IC(50)) of the immobilized enzyme was 85 mM. Treatment of dyes with the immobilized laccase reduced their toxicities (based on the oxygen consumption rate of Pseudomonas putida) by up to 80% (anthraquinonic dyes). Textile effluents decolorized with T. hirsuta or the laccase were used for dyeing. Metabolites and/or enzyme protein strongly interacted with the dyeing process indicated by lower staining levels (K/S) values than obtained with a blank using water. However, when the effluents were decolorized with immobilized laccase, they could be used for dyeing and acceptable color differences (DeltaE*) below 1.1 were measured for most dyes. PMID:10919791

  15. Design and synthesis of a noncentrosymmetric Dipyrromethene Dye

    SciTech Connect

    Meinhardt, M.B.; Cahill, P.A.; Kowalczyk, T.C.; Singer, K.D.

    1994-12-31

    Semiempirical methods were applied to the design of a new second order nonlinear optical (NLO) dye through noncentrosymmetric modifications to the symmetric dipyrromethene boron difluoride chromophore. Computational evaluations of candidate structures suggested that a synthetically accessible methoxyindole modification would have second order NLO properties. This new dye consists of 4 fused rings, is soluble in polar organic solvents and has a large molar extinction coefficient (86 {times} 103). Its measured hyperpolarizability, {beta}, is -44 {times} 10{sup {minus}30} esu at 1367 nm. The methoxyindole therefore induces moderate asymmetry to the chromophore.

  16. Hair Dye and Hair Relaxers

    MedlinePLUS

    ... Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco ... Print and Share (615 KB) En Español Hair dye is used to color your hair. Hair relaxers are used to make ...

  17. 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.

  18. A NIR-remote controlled upconverting nanoparticle: an improved tool for living cell dye-labeling

    NASA Astrophysics Data System (ADS)

    Zheng, Bin; Gong, Xiaoqun; Wang, Hanjie; Wang, Sheng; Wang, Huiquan; Li, Wei; Tan, Jian; Chang, Jin

    2015-10-01

    In living cells, due to the selective permeability and complicated cellular environment, the uptake efficiency and fluorescence decay of organic dyes during dye-labeling may be influenced, which may eventually result in poor fluorescent imaging. In this work, a protocol of UCNs@mSiO2-(FA and Azo) core-shell nanocarriers was designed and prepared successfully. The core-shell nanocarriers were assembled from two parts, including a mesoporous silica shell surface modified by folate (FA) and azobenzene (Azo), and an upconverting nanocrystal (UCN) core. The mesoporous silica shell is used for loading organic dyes and conjugating folate which helps to enhance the cellular uptake of nanocarriers. The UCN core works as a transducer to convert near infrared (NIR) light to local UV and visible light to activate a back-and-forth wagging motion of azobenzene molecules on the surface, while the azobenzene acts as a molecular impeller for propelling the release of organic dyes. The nanocarriers of loading organic dyes can maintain the stability of the fluorescent imaging effect better than free organic dyes. The experimental results show that with the help of the nanoparticle, cell uptake efficiency of the model dyes of rhodamine and 4?, 6-diamidino-2-phenylindole (DAPI) was significantly improved. The release of dyes can only be triggered by NIR light exposure and their quantity is highly dependent on the duration of NIR light exposure, thus realizing NIR-regulated dye release spatiotemporally. Our work may open a novel avenue for precisely controlling UCN-based living cell imaging in biotechnology and diagnostics, as well as studying cell dynamics, cell-cell interactions, and tissue morphogenesis.

  19. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste

    NASA Astrophysics Data System (ADS)

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-Aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-10-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T-) electrolyte.

  20. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste

    PubMed Central

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-01-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T?) electrolyte. PMID:26458745

  1. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste.

    PubMed

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-Aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-01-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T(-)) electrolyte. PMID:26458745

  2. Dye-sensitized polyoxometalate for visible-light-driven photoelectrochemical cells.

    PubMed

    Gao, Junkuo; Miao, Jianwei; Li, Yongxin; Ganguly, Rakesh; Zhao, Yang; Lev, Ovadia; Liu, Bin; Zhang, Qichun

    2015-08-28

    A simple and facile one-step method for the synthesis of an organic dye-functionalized polyoxometalate (POM) hybrid with visible-light photo-response was reported. The POM hybrid was fully characterized via single crystal XRD, powder XRD, FTIR and elemental analysis. The reaction of the organic dye with inorganic salts gave the dye-functionalized POM (MoBB3), in which the POM cluster was formed in situ. The electronic absorption peak of this hybrid was successfully extended beyond 680 nm. Photoelectrochemical measurement indicated that MoBB3 was photoresponsive under visible-light illumination, suggesting that it is an n-type (electron conductive) semiconducting material. This result might offer a method for the design of novel organic dye-functionalized POMs for photoelectric applications. PMID:26200796

  3. Discovery of Black Dye Crystal Structure Polymorphs: Implications for Dye Conformational Variation in Dye-Sensitized Solar Cells.

    PubMed

    Cole, Jacqueline M; Low, Kian Sing; Gong, Yun

    2015-12-23

    We present the discovery of a new crystal structure polymorph (1) and pseudopolymorph (2) of the Black Dye, one of the world's leading dyes for dye-sensitized solar cells, DSSCs (10.4% device performance efficiency). This reveals that Black Dye molecules can adopt multiple low-energy conformers. This is significant since it challenges existing models of the Black Dye···TiO2 adsorption process that renders a DSSC working electrode; these have assumed a single molecular conformation that refers to the previously reported Black Dye crystal structure (3). The marked structural differences observed between 1, 2, and 3 make the need for modeling multiple conformations more acute. Additionally, the ordered form of the Black Dye (1) provides a more appropriate depiction of its anionic structure, especially regarding its anchoring group and NCS bonding descriptions. The tendency toward NCS ligand isomerism, evidenced via the disordered form 2, has consequences for electron injection and electron recombination in Black Dye embedded DSSC devices. Dyes 2 and 3 differ primarily by the absence or presence of a solvent of crystallization, respectively; solvent environment effects on the dye are thereby elucidated. This discovery of multiple Black Dye conformers from diffraction, with atomic-level definition, complements recently reported nanoscopic evidence for multiple dye conformations existing at a dye···TiO2 interface, for a chemically similar DSSC dye; those results emanated from imaging and spectroscopy, but were unresolved at the submolecular level. Taken together, these findings lead to the general notion that multiple dye conformations should be explicitly considered when modeling dye···TiO2 interfaces in DSSCs, at least for ruthenium-based dye complexes. PMID:26599130

  4. [Dye analytical investigations on the polarization microscopy detection of collagen with Sominrot 4B (Part II)].

    PubMed

    Schräpler, R; Schmidt, T; Schultka, R; Hepp, W D

    1991-01-01

    We use the disazo dyestuff Solaminrot 4B for the visualization of collagen fibres in the morphological substratum investigated. The dye selectively enhance the birefringency of the fibres. Therefore, the parts of this paper are dealing with the dye properties of 2 charges of Solaminrot 4B produced by Chemie AG Bitterfeld--Wolfen. The 1st charge contain supplementary substances; the 2nd charge is without ones. We used various physicochemical methods, e.g. chromatography, spectroscopy, and electrophoresis. Moreover, we analyzed the solubility of dye in inorganic and organic solventia, the phase dispersion in benzen and octanol, the influence of the dye probes on the pH values of the dye solutions, and so on. The results indicate that the physicochemical properties of both charges investigated by us are partially different. This is important for the application of Sirius Red dyestuffs to the histological staining procedures. PMID:2048392

  5. Chemically Altering the Solubility and Durability of Dyes for Sensitized Solar Cells.

    PubMed

    Maniam, Subashani; Holmes, Andrew B; Leeke, Gary A; Bilic, Ante; Collis, Gavin E

    2015-08-21

    By designing dyes with fluoroalkyl groups, the optical and electronic properties of the alkyl analogue were maintained while dramatically altering the solubility. Dyes, F-TABTA (8) and its masked derivative F-TABTSi (9), that enable them to be deposited under conventional organic solvent and scCO2 conditions, respectively, were developed. In liquid DSSC devices, the fluoroalkyl dye (F-TABTA, 8) performs slightly better than its alkyl analogue (D21L6, 10), and interestingly, it was found that the former device showed better stability over time. Deploying the silyl-masked precursor F-TABTSi (9), this dye was deposited onto TiO2 photoanodes from scCO2 in very short contact times (2.5 h), and ECEs of 7.70% were obtained that exceed the performance of the alkyl dye when deposited by conventional methods. PMID:26238416

  6. The synthesis and spectral properties of a stimuli-responsive D-?-A charge transfer dye

    NASA Astrophysics Data System (ADS)

    Kim, Sung-Hoon; Gwon, Seon-Yeong; Bae, Jin-Seok; Son, Young-A.

    2011-01-01

    A new donor-?-acceptor (D-?-A) type isophorone dye was synthesized by the condensation reaction between 2-(3,5,5-trimethylcyclohex-2-enylidene)-malononitrile and indole-3-carboxaldehyde. The chemical structure of the dye was characterized by 1H NMR, EA and MS. A novel, chromogenic, fluorescent dye based on indol as donor unit and isophorone as acceptor unit displayed marked UV-visible absorption changes and highly selective fluorescence quenching in the presence of fluoride ion. The dye also exhibited sizeable colour changes when used as a pH-induced molecular switch and as a detector for volatile organic compounds. The absorption and fluorescent intensity of the dye can be reversibly selected by protonation/deprotonation of the amine moiety via control of intramolecular charge transfer (ICT), leading to a molecular switch with "on" and "off" states.

  7. Non-Carbon Dyes For Platic Scintillators- Report

    SciTech Connect

    Teprovich, J.; Colon-Mercado, H.; Gaillard, J.; Sexton, L.; Washington, A.; Ward, P.; Velten, J.

    2015-10-19

    Scintillation based detectors are desirable for many radiation detection applications (portal and border monitoring, safeguards verification, contamination detection and monitoring). The development of next generation scintillators will require improved detection sensitivity for weak gamma ray sources, and fast and thermal neutron quantification. Radiation detection of gamma and neutron sources can be accomplished with organic scintillators, however, the single crystals are difficult to grow for large area detectors and subject to cracking. Alternatives to single crystal organic scintillators are plastic scintillators (PS) which offer the ability to be shaped and scaled up to produce large sized detectors. PS is also more robust than the typical organic scintillator and are ideally suited for deployment in harsh real-world environments. PS contain a mixture of dyes to down-convert incident radiation into visible light that can be detected by a PMT. This project will evaluate the potential use of nano-carbon dyes in plastic scintillators.

  8. Sea dye marker provides visibility for 20 hours

    NASA Technical Reports Server (NTRS)

    De Laat, F.

    1966-01-01

    Sea dye marker block releases a visible slick which lasts at least twelve hours. The dye marker uses a fluorescent dye in a heat cured binder which, when immersed in seawater, releases the dye at a controlled rate.

  9. Metal-free tetrathienoacene sensitizers for high-performance dye-sensitized solar cells.

    PubMed

    Zhou, Nanjia; Prabakaran, Kumaresan; Lee, Byunghong; Chang, Sheng Hsiung; Harutyunyan, Boris; Guo, Peijun; Butler, Melanie R; Timalsina, Amod; Bedzyk, Michael J; Ratner, Mark A; Vegiraju, Sureshraju; Yau, Shuehlin; Wu, Chun-Guey; Chang, Robert P H; Facchetti, Antonio; Chen, Ming-Chou; Marks, Tobin J

    2015-04-01

    A new series of metal-free organic chromophores (TPA-TTAR-A (1), TPA-T-TTAR-A (2), TPA-TTAR-T-A (3), and TPA-T-TTAR-T-A (4)) are synthesized for application in dye-sensitized solar cells (DSSC) based on a donor-?-bridge-acceptor (D-?-A) design. Here a simple triphenylamine (TPA) moiety serves as the electron donor, a cyanoacrylic acid as the electron acceptor and anchoring group, and a novel tetrathienoacene (TTA) as the ?-bridge unit. Because of the extensively conjugated TTA ?-bridge, these dyes exhibit high extinction coefficients (4.5-5.2 × 10(4) M(-1) cm(-1)). By strategically inserting a thiophene spacer on the donor or acceptor side of the molecules, the electronic structures of these TTA-based dyes can be readily tuned. Furthermore, addition of a thiophene spacer has a significant influence on the dye orientation and self-assembly modality on TiO2 surfaces. The insertion of a thiophene between the ?-bridge and the cyanoacrylic acid anchoring group in TPA-TTAR-T-A (dye 3) promotes more vertical dye orientation and denser packing on TiO2 (molecular footprint = 79 Å(2)), thus enabling optimal dye loading. Using dye 3, a DSSC power conversion efficiency (PCE) of 10.1% with Voc = 0.833 V, Jsc = 16.5 mA/cm(2), and FF = 70.0% is achieved, among the highest reported to date for metal-free organic DSSC sensitizers using an I(-)/I3(-) redox shuttle. Photophysical measurements on dye-grafted TiO2 films reveal that the additional thiophene unit in dye 3 enhances the electron injection efficiency, in agreement with the high quantum efficiency. PMID:25768124

  10. 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.

  11. Isolation and characterization of Bacillus thuringiensis for acid red 119 dye decolourisation.

    PubMed

    Dave, Shailesh R; Dave, Riddhi H

    2009-01-01

    Studies were carried out to isolate Acid red 119 (AR-119) resistant and decolourising bacteria from dye contaminated soil and water samples. Six morphologically distinct bacterial isolates resistant to 100 ppm AR-119 dye were isolated directly from the soil and waste contaminated with azo dyes. The most efficient isolate, which showed decolourisation zone of 44 mm on 100 ppm AR-119 containing plate was identified as Bacillus thuringiensis SRDD. Gradual adaptation increased the efficiency of the isolate and within 7h of incubation it showed decolourisation up to 1000 ppm of AR-119 dye in liquid medium. Addition of 300 ppm of AR-119 in each step in ongoing dye decolourisation flask gave more than 90% decolourisation of 300 ppm AR-119 in time as short as 1.25 h. The developed B. thuringiensis showed 50-60% decolourisation of 5000 ppm AR-119 in 7d of incubation. This organism was also able to remove more than 98%, 92%, 95% and 95% colour of C.I. Acid brown 14, C.I. Acid black 210, C.I. Acid violet 90 and C.I. Acid yellow 42 azo dyes at 100 ppm concentration in 24h, respectively. When the developed isolate was studied for bioremediation of actual azo dye contaminated waste it removed 70% colour from the waste in 24h. The developed B. thuringiensis exhibited excellent resistance and decolourisation ability to AR-119 and other acid azo dyes. PMID:18590958

  12. Clean Photothermal Heating and Controlled Release From Near Infrared Dye Doped Nanoparticles Without Oxygen Photosensitization

    PubMed Central

    Guha, Samit; Shaw, Scott K.; Spence, Graeme T.; Roland, Felicia M.; Smith, Bradley D.

    2015-01-01

    The photothermal heating and release properties of biocompatible organic nanoparticles, doped with a near-infrared croconaine (Croc) dye, were compared with analogous nanoparticles doped with the common near-infrared dyes ICG and IR780. Separate formulations of lipid-polymer-hybrid nanoparticles and liposomes, each containing Croc dye, absorbed strongly at 808 nm and generated clean laser-induced heating (no production of 1O2 and no photobleaching of the dye). In contrast, laser-induced heating of nanoparticles containing ICG or IR780 produced reactive 1O2 leading to bleaching of the dye and also decomposition of co-encapsulated payload such as the drug Doxorubicin. Croc dye was especially useful as a photothermal agent for laser controlled release of chemically sensitive payload from nanoparticles. Solution state experiments demonstrated repetitive fractional release of water soluble fluorescent dye from the interior of thermosensitive liposomes. Additional experiments used a focused laser beam to control leakage from immobilized liposomes with very high spatial and temporal precision. The results indicate that fractional photothermal leakage from nanoparticles doped with Croc dye is a promising method for a range of controlled release applications. PMID:26149326

  13. 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

  14. Tuning the electrical and optical properties of diketopyrrolopyrrole complexes for panchromatic dye-sensitized solar cells.

    PubMed

    Qu, Sanyin; Qin, Chuanjiang; Islam, Ashraful; Hua, Jianli; Chen, Han; Tian, He; Han, Liyuan

    2012-12-01

    A series of metal-free organic dyes that were bridged by a diketopyrrolopyrrole moiety and were composed of indoline and triphenylamine as donor groups and furan and benzene as conjugated spacer groups were designed and synthesized for use in dye-sensitized solar cells (DSCs). The photophysical properties, electrochemical properties, and performance of the DSCs were related to the structure of their corresponding dyes. Their absorption spectra broadened upon the introduction of the indoline and heterocyclic furan moieties through fine-tuning of their molecular configuration. The overall conversion efficiencies of DSCs that were based on these dyes ranged from 5.14-6.53%. Among the four dyes that were tested, indoline-based ID01 and ID02 showed higher efficiencies (6.35% and 6.53%) as a result of their improved light-harvesting efficiency and larger electron driving force. The ID01 dye, which contained an indoline moiety as an electron donor and a furan group as a ?-conjugated linker, showed an excellent monochromatic incident-photon-to-current-conversion efficiency (IPCE) spectrum (350-650?nm) with a maximum value of 78% in the high plateau region and an onset value close to 800?nm. Intensity-modulated photovoltage spectroscopy (IMVS) and impedance spectroscopy (IS) revealed that dyes that contained benzene conjugation spacers suppressed the charge-recombination rate more efficiently than dyes that contained furan spacers, thereby resulting in improved photovoltage. PMID:23015395

  15. Novel near-infrared carboxylated 1,3-indandione sensitizers for highly efficient flexible dye-sensitized solar cells.

    PubMed

    Shibayama, Naoyuki; Inoue, Yukiko; Abe, Masahiro; Kajiyama, Shingo; Ozawa, Hironobu; Miura, Hidetoshi; Arakawa, Hironori

    2015-08-18

    Three novel metal-free organic dyes (DN458, DN475 and DN484) were designed for use in plastic-substrate dye-sensitized solar cells (PDSCs). The photoelectric conversion region of DN475 was successfully expanded into the near-infrared region. As a result, an energy conversion efficiency of 5.76% was achieved. PMID:26166712

  16. DOI: 10.1002/chem.200501541 Squaraine-Derived Rotaxanes: Highly Stable, Fluorescent Near-IR Dyes

    E-print Network

    Smith, Bradley D.

    DOI: 10.1002/chem.200501541 Squaraine-Derived Rotaxanes: Highly Stable, Fluorescent Near-IR Dyes with optical imaging is restricted tissue penetration, however, it is pre- dicted that low-energy, near-IR (NIR, there is no organic NIR dye that has all of these desirable properties.[5] Abstract: Squaraines are fluorescent, near-IR

  17. Elucidating the structure-property relationships of donor-?-acceptor dyes for dye-sensitized solar cells (DSSCs) through rapid library synthesis by a one-pot procedure.

    PubMed

    Fuse, Shinichiro; Sugiyama, Sakae; Maitani, Masato M; Wada, Yuji; Ogomi, Yuhei; Hayase, Shuzi; Katoh, Ryuzi; Kaiho, Tatsuo; Takahashi, Takashi

    2014-08-18

    The creation of organic dyes with excellent high power conversion efficiency (PCE) is important for the further improvement of dye-sensitized solar cells. We wish to describe the rapid synthesis of a 112-membered donor-?-acceptor dye library by a one-pot procedure, evaluation of PCEs, and elucidation of structure-property relationships. No obvious correlations between ?, and the ? were observed, whereas the HOMO and LUMO levels of the dyes were critical for ?. The dyes with a more positive E(HOMO), and with an E(LUMO)<-0.80?V, exerted higher PCEs. The proper driving forces were crucial for a high J(sc), and it was the most important parameter for a high ?. The above criteria of E(HOMO) and E(LUMO) should be useful for creating high PCE dyes; nevertheless, that was not sufficient for identifying the best combination of donor, ?, and acceptor blocks. Combinatorial synthesis and evaluation was important for identifying the best dye. PMID:24954633

  18. Dye Sensitized Tandem Photovoltaic Cells

    SciTech Connect

    Barber, Greg D.

    2009-12-21

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

  19. Single mode pulsed dye laser oscillator

    DOEpatents

    Hackel, R.P.

    1992-11-24

    A single mode pulsed dye laser oscillator is disclosed. The dye laser oscillator provides for improved power efficiency by reducing the physical dimensions of the overall laser cavity, which improves frequency selection capability. 6 figs.

  20. 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...

  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-sensitized solar cells, the excited ERDs must be able to efficiently transfer energy to the sensitizing dyes, TT1, to increase the overall power conversion efficiency of a dye-sensitized solar cell (DSC) from 3

  2. Modeling the efficiency of Frster resonant energy transfer from energy relay dyes in dye-

    E-print Network

    McGehee, Michael

    Modeling the efficiency of Förster resonant energy transfer from energy relay dyes in dye resonant energy transfer can improve the spectral breadth, absorption and energy conversion efficiency of dye sensitized solar cells. In this design, unattached relay dyes absorb the high energy photons

  3. 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.

  4. 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.

  5. 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.

  6. Reactive Fluorescent Dyes For Urethane Coatings

    NASA Technical Reports Server (NTRS)

    Willis, Paul B.; Cuddihy, Edward F.

    1991-01-01

    Molecules of fluorescent dyes chemically bound in urethane conformal-coating materials to enable nondestructive detection of flaws in coats through inspection under ultraviolet light, according to proposal. Dye-bonding technique prevents outgassing of dyes, making coating materials suitable for use where flaw-free coats must be assured in instrumentation or other applications in which contamination by outgassing must be minimized.

  7. PHOTOLYSIS OF SMOKE DYES ON SOILS

    EPA Science Inventory

    Photolysis of an azo, a quinophthalone, and several anthraquinone smoke dyes was studied on soil surfaces. nitially, rapid photodegradation of each dye occurred, followed by a period of much slower rate of loss, indicating that the remaining fraction of the dye was photochemicall...

  8. Solvatochromism and temperature effects on the electronic absorption spectra of some azo dyes

    NASA Astrophysics Data System (ADS)

    Alizadeh, Kamal; Seyyedi, Susan; Shamsipur, Mojtaba; Rouhani, Shohreh; Haghbeen, Kamaladin

    2009-10-01

    The UV-visible electronic spectra of some azo dyes have been studied. The different bands observed in the electronic spectra of the compounds in various organic solvents have been assigned to the proper electronic transitions. The solvatochromic behaviour of these compounds was investigated by studying their visible spectra in several pure and mixed organic solvents. The longer wavelength band displayed by para-nitro azo dyes is assigned to an intermolecular charge-transfer transition. The solvated H-bonding complexes formed between N, N-dimethylformamide and the para-nitro azo dyes were investigated. ? G and formation constant, the values of Kf of the molecular complexes formed in solution have been determined. The effects of increase of temperature and concentration dependent spectroscopic changes on the longer wavelength visible band of para-nitro azo dyes were also investigated.

  9. Organics.

    ERIC Educational Resources Information Center

    Chian, Edward S. K.; DeWalle, Foppe B.

    1978-01-01

    Presents water analysis literature for 1978. This review is concerned with organics, and it covers: (1) detergents and surfactants; (2) aliphatic and aromatic hydrocarbons; (3) pesticides and chlorinated hydrocarbons; and (4) naturally occurring organics. A list of 208 references is also presented. (HM)

  10. Anthraquinone dyes for superhydrophobic cotton.

    PubMed

    Salabert, J; Sebastián, R M; Vallribera, A

    2015-09-28

    Water-repellent, self-cleaning and stain resistant textiles are of interest for industrial applications. Anthraquinone reactive dyes were covalently grafted onto cotton fabric surfaces obtaining bright colors with good wash-fastness properties and giving rise to breathable superhydrophobic textiles with self-cleaning properties. PMID:26265296

  11. Dye-doped silica-based nanoparticles for bioapplications

    NASA Astrophysics Data System (ADS)

    Nhung Tran, Hong; Nghiem, Thi Ha Lien; Thuy Duong Vu, Thi; Tan Pham, Minh; Van Nguyen, Thi; Trang Tran, Thu; Chu, Viet Ha; Thuan Tong, Kim; Thuy Tran, Thanh; Le, Thi Thanh Xuan; Brochon, Jean-Claude; Quy Nguyen, Thi; Nhung Hoang, My; Nguyen Duong, Cao; Thuy Nguyen, Thi; Hoang, Anh Tuan; Hoa Nguyen, Phuong

    2013-12-01

    This paper presents our recent research results on synthesis and bioapplications of dye-doped silica-based nanoparticles. The dye-doped water soluble organically modified silicate (ORMOSIL) nanoparticles (NPs) with the size of 15-100 nm were synthesized by modified Stöber method from methyltriethoxysilane CH3Si(OCH3)3 precursor (MTEOS). Because thousands of fluorescent dye molecules are encapsulated in the silica-based matrix, the dye-doped nanoparticles are extremely bright and photostable. Their surfaces were modified with bovine serum albumin (BSA) and biocompatible chemical reagents. The highly intensive luminescent nanoparticles were combined with specific bacterial and breast cancer antigen antibodies. The antibody-conjugated nanoparticles can identify a variety of bacterium, such as Escherichia coli O157:H7, through antibody-antigen interaction and recognition. A highly sensitive breast cancer cell detection has been achieved with the anti-HER2 monoclonal antibody-nanoparticles complex. These results demonstrate the potential to apply these fluorescent nanoparticles in various biodetection systems.

  12. 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.

  13. 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.

  14. Dyeing of Jute with Reactive Dyes: Optimisation of the Process Variables and Assessment of Colourfastness Characteristics

    NASA Astrophysics Data System (ADS)

    Samanta, A. K.; Chakraborty, Sharmistha; Guha Roy, T. K.

    2012-08-01

    This paper deals with the studies on the effect of dye concentration, electrolyte (common salt) concentration, dyeing time, dyeing temperature, soda ash concentration, pH of the dye solution and material to liquor ratio (MLR) on colour strength and other colour parameters after being dyed of jute fabrics with reactive dyes, namely, Turquoise blue, Lemon Yellow, Red CN colours. The dye absorption increases with increase in electrolyte (common salt) concentration, dyeing time, dyeing temperature, soda ash concentration, pH and decreases with increase of MLR. Colour fastness to wash, light and rubbing for the dyed samples has been studied and reported. It is observed that reactive dye gives overall good colour fastness to both washing and rubbing. But the light fastness has been found to be moderate only, due to the UV-light initiated fading of jute fibre itself change of the colour substrate, ie, undyed material. This colour fastness has been significantly resolved by post treatment with 1 % benzotriazole.

  15. Degradation characteristic of monoazo, diazo and anthraquinone dye by UV/H{sub 2}O{sub 2} process

    SciTech Connect

    Abidin, Che Zulzikrami Azner E-mail: drfahmi@unimap.edu.my E-mail: fatinnadhirah89@gmail.com; Fahmi, Muhammad Ridwan E-mail: drfahmi@unimap.edu.my E-mail: fatinnadhirah89@gmail.com; Fazara, Md Ali Umi E-mail: drfahmi@unimap.edu.my E-mail: fatinnadhirah89@gmail.com; Nadhirah, Siti Nurfatin E-mail: drfahmi@unimap.edu.my E-mail: fatinnadhirah89@gmail.com

    2014-10-24

    In this study, the degradation characteristic of monoazo, diazo and anthraquinone dye by UV/H{sub 2}O{sub 2} process was evaluated based on the trend of color, chemical oxygen demand (COD) and total organic carbon (TOC) removal. Three types of dyes consist of monoazo, diazo and anthraquinone dyes were used to compare the degradation mechanism of the dyes. The UV/H{sub 2}O{sub 2} experiments were conducted in a laboratory scale cylindrical glass reactor operated in semi-batch mode. The UV/Vis characterization of monoazo, diazo and anthraquinone dye indicated that the rapid degradation of the dyes by UV/H{sub 2}O{sub 2} process is meaningful with respect to decolourization, as a result of the azo bonds and substitute antraquinone chromophore degradation. However, this process is not efficient for aromatic amines removal. The monoazo MO was difficult to be decolorized than diazo RR120 dye, which imply that number of sulphonic groups in the dye molecules determines the reactivity with hydroxyl radical. The increased in COD removal is the evidence for oxidation and decreased in carbon content of dye molecules. TOC removal analysis shows that low TOC removal of monoazo MO and diazo RR120, as compared to anthraquinone RB19 may indicate an accumulation of by-products that are resistant to the H{sub 2}O{sub 2} photolysis.

  16. Cell type-specific delivery of short interfering RNAs by dye-functionalised theranostic nanoparticles

    PubMed Central

    Press, Adrian T.; Traeger, Anja; Pietsch, Christian; Mosig, Alexander; Wagner, Michael; Clemens, Mark G.; Jbeily, Nayla; Koch, Nicole; Gottschaldt, Michael; Bézière, Nicolas; Ermolayev, Volodymyr; Ntziachristos, Vasilis; Popp, Jürgen; Kessels, Michael M.; Qualmann, Britta; Schubert, Ulrich S.; Bauer, Michael

    2014-01-01

    Efficient delivery of short interfering RNAs reflects a prerequisite for the development of RNA interference therapeutics. Here, we describe highly specific nanoparticles, based on near infrared fluorescent polymethine dye-derived targeting moieties coupled to biodegradable polymers. The fluorescent dye, even when coupled to a nanoparticle, mimics a ligand for hepatic parenchymal uptake transporters resulting in hepatobiliary clearance of approximately 95% of the dye within 45?min. Body distribution, hepatocyte uptake and excretion into bile of the dye itself, or dye-coupled nanoparticles can be tracked by intravital microscopy or even non-invasively by multispectral optoacoustic tomography. Efficacy of delivery is demonstrated in vivo using 3-hydroxy-3-methyl-glutaryl-CoA reductase siRNA as an active payload resulting in a reduction of plasma cholesterol levels if siRNA was formulated into dye-functionalised nanoparticles. This suggests that organ-selective uptake of a near infrared dye can be efficiently transferred to theranostic nanoparticles allowing novel possibilities for personalised silencing of disease-associated genes. PMID:25470305

  17. Spectroscopic properties and amplified spontaneous emission of fluorescein laser dye in ionic liquids as green media

    NASA Astrophysics Data System (ADS)

    AL-Aqmar, Dalal M.; Abdelkader, H. I.; Abou Kana, Maram T. H.

    2015-09-01

    The use of ionic liquids (ILs) as milieu materials for laser dyes is a promising field and quite competitive with volatile organic solvents and solid state-dye laser systems. This paper investigates some photo-physical parameters of fluorescein dye incorporated into ionic liquids; 1-Butyl-3-methylimidazolium chloride (BMIM Cl), 1-Butyl-3-methylimidazolium tetrachloroaluminate (BMIM AlCl4) and 1-Butyl-3-methylimidazolium tetrafluoroborate (BMIM BF4) as promising host matrix in addition to ethanol as reference. These parameters are: absorption and emission cross-sections, fluorescence lifetime and quantum yield, in addition to the transition dipole moment, the attenuation length and oscillator strength were also investigated. Lasing characteristics such as amplified spontaneous emission (ASE), the gain, and the photostability of fluorescein laser dye dissolved in different host materials were assessed. The composition and properties of the matrix of ILs were found that it has great interest in optimizing the laser performance and photostability of the investigated laser dye. Under transverse pumping of fluorescein dye by blue laser diode (450 nm) of (400 mW), the initial ASE for dye dissolved in BMIM AlCl4 and ethanol were decreased to 39% and 36% respectively as time progressed 132 min. Relatively high efficiency and high fluorescence quantum yield (11.8% and 0.82% respectively) were obtained with good photostability in case of fluorescein in BMIM BF4 that was decreased to ?56% of the initial ASE after continuously pumping with 400 mW for 132 min.

  18. Decolorization of reactive textile dyes using water falling film dielectric barrier discharge.

    PubMed

    Doj?inovi?, Biljana P; Rogli?, Goran M; Obradovi?, Bratislav M; Kuraica, Milorad M; Kosti?, Mirjana M; Neši?, Jelena; Manojlovi?, Dragan D

    2011-08-30

    Decolorization of reactive textile dyes Reactive Black 5, Reactive Blue 52, Reactive Yellow 125 and Reactive Green 15 was studied using advanced oxidation processes (AOPs) in a non-thermal plasma reactor, based on coaxial water falling film dielectric barrier discharge (DBD). Used initial dye concentrations in the solution were 40.0 and 80.0mg/L. The effects of different initial pH of dye solutions, and addition of homogeneous catalysts (H(2)O(2), Fe(2+) and Cu(2+)) on the decolorization during subsequent recirculation of dye solution through the DBD reactor, i.e. applied energy density (45-315kJ/L) were studied. Influence of residence time was investigated over a period of 24h. Change of pH values and effect of pH adjustments of dye solution after each recirculation on the decolorization was also tested. It was found that the initial pH of dye solutions and pH adjustments of dye solution after each recirculation did not influence the decolorization. The most effective decolorization of 97% was obtained with addition of 10mM H(2)O(2) in a system of 80.0mg/L Reactive Black 5 with applied energy density of 45kJ/L, after residence time of 24h from plasma treatment. Toxicity was evaluated using the brine shrimp Artemia salina as a test organism. PMID:21703757

  19. Nonlinear optical properties of poly(methyl methacrylate) thin films doped with Bixa Orellana dye

    NASA Astrophysics Data System (ADS)

    Zongo, S.; Kerasidou, A. P.; Sone, B. T.; Diallo, A.; Mthunzi, P.; Iliopoulos, K.; Nkosi, M.; Maaza, M.; Sahraoui, B.

    2015-06-01

    Natural dyes with highly delocalized ?-electron systems are considered as promising organic materials for nonlinear optical applications. Among these dyes, Bixa Orellana dye with extended ?-electron delocalization is one of the most attractive dyes. Bixa Orellana dye-doped Poly(methyl methacrylate) (PMMA) thin films were prepared through spin coating process for linear and nonlinear optical properties investigation. Atomic force microscopy (AFM) was used to evaluate the roughness of the thin films. The optical constants n and k were evaluated by ellipsometric spectroscopy. The refractive index had a maximum of about 1.456 at 508.5, 523.79 and 511.9 nm, while the maximum of k varies from 0.070 to 0.080 with the thickness. The third order nonlinear optical properties of the hybrid Bixa Orellana dye-PMMA polymer were investigated under 30 ps laser irradiation at 1064 nm with a repetition rate of 10 Hz. In particular the third-order nonlinear susceptibility has been determined by means of the Maker Fringes technique. The nonlinear third order susceptibility was found to be 1.00 × 10-21 m2 V-2 or 0.72 × 10-13 esu. Our studies provide concrete evidence that the hybrid-PMMA composites of Bixa dye are prospective candidates for nonlinear material applications.

  20. Cell type-specific delivery of short interfering RNAs by dye-functionalised theranostic nanoparticles

    NASA Astrophysics Data System (ADS)

    Press, Adrian T.; Traeger, Anja; Pietsch, Christian; Mosig, Alexander; Wagner, Michael; Clemens, Mark G.; Jbeily, Nayla; Koch, Nicole; Gottschaldt, Michael; Bézière, Nicolas; Ermolayev, Volodymyr; Ntziachristos, Vasilis; Popp, Jürgen; Kessels, Michael M.; Qualmann, Britta; Schubert, Ulrich S.; Bauer, Michael

    2014-12-01

    Efficient delivery of short interfering RNAs reflects a prerequisite for the development of RNA interference therapeutics. Here, we describe highly specific nanoparticles, based on near infrared fluorescent polymethine dye-derived targeting moieties coupled to biodegradable polymers. The fluorescent dye, even when coupled to a nanoparticle, mimics a ligand for hepatic parenchymal uptake transporters resulting in hepatobiliary clearance of approximately 95% of the dye within 45?min. Body distribution, hepatocyte uptake and excretion into bile of the dye itself, or dye-coupled nanoparticles can be tracked by intravital microscopy or even non-invasively by multispectral optoacoustic tomography. Efficacy of delivery is demonstrated in vivo using 3-hydroxy-3-methyl-glutaryl-CoA reductase siRNA as an active payload resulting in a reduction of plasma cholesterol levels if siRNA was formulated into dye-functionalised nanoparticles. This suggests that organ-selective uptake of a near infrared dye can be efficiently transferred to theranostic nanoparticles allowing novel possibilities for personalised silencing of disease-associated genes.

  1. Artificial evolution of coumarin dyes for dye sensitized solar cells.

    PubMed

    Venkatraman, Vishwesh; Abburu, Sailesh; Alsberg, Bjørn Kåre

    2015-10-14

    The design and discovery of novel molecular structures with optimal properties has been an ongoing effort for materials scientists. This field has in general been dominated by experiment driven trial-and-error approaches that are often expensive and time-consuming. Here, we investigate if a de novo computational design methodology can be applied to the design of coumarin-based dye sensitizers with improved properties for use in Grätzel solar cells. To address the issue of synthetic accessibility of the designed compounds, a fragment-based assembly is employed, wherein the combination of chemical motifs (derived from the existing databases of structures) is carried out with respect to user-adaptable set of rules. Rather than using computationally intensive density functional theory (DFT)/ab initio methods to screen candidate dyes, we employ quantitative structure-property relationship (QSPR) models (calibrated from empirical data) for rapid estimation of the property of interest, which in this case is the product of short circuit current (Jsc) and open circuit voltage (Voc). Since QSPR models have limited validity, pre-determined applicability domain criteria are used to prevent unacceptable extrapolation. DFT analysis of the top-ranked structures provides supporting evidence of their potential for dye sensitized solar cell applications. PMID:26428071

  2. New Analytical Method for the Determination of Detergent Concentration in Water by Fabric Dyeing

    ERIC Educational Resources Information Center

    Seng, Set; Kita, Masakazu; Sugihara, Reiko

    2007-01-01

    The use of harmful organic solvents in classrooms has become a critical issue of concern in the field of chemistry education. This article describes a classroom activity at a high school in which an acrylic fabric was used as the extraction medium in the analysis of the detergent concentration in water instead of organic solvents. Dyes were used…

  3. Multiwalled carbon nanotubes dispersed in carminic acid for the development of catalase based biosensor for selective amperometric determination of H(2)O(2) and iodate.

    PubMed

    Periasamy, Arun Prakash; Ho, Ya-Hui; Chen, Shen-Ming

    2011-11-15

    We report the preparation of stable dispersion of multiwalled carbon nanotubes (MWCNTs) using carminic acid (CA) as a dispersing agent. The transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) results confirmed that MWCNT is well dispersed in CA aqueous solution and CA has been well adsorbed at MWCNT walls. Fourier transform infrared (FTIR) and UV-vis absorption spectra results also confirmed the adsorption of CA at MWCNT. To develop a highly selective amperometric biosensor for H(2)O(2) and iodate, the model enzyme catalase (CAT) was immobilized at CACNT modified glassy carbon electrode surface. The immobilized CAT exhibits well defined quasi reversible redox peaks at a formal potential (E°') of -0.559V in 0.05M pH 7 phosphate buffer solution (PBS). The proposed CAT/CACNT biosensor exhibits excellent amperometric response towards H(2)O(2) and iodate in the linear concentration range between 10?M to 3.2mM and 0.01-2.16mM. The sensitivity values are 287.98?AmM(-1)cm(-2) and 0.253mAmM(-1)cm(-2), respectively. Moreover, the developed CAT biosensor exhibits high affinity for H(2)O(2) and iodate with good selectivity. PMID:21900003

  4. Kinetic, equilibrium and thermodynamic studies on sorption of uranium and thorium from aqueous solutions by a selective impregnated resin containing carminic acid.

    PubMed

    Rahmani-Sani, Abolfazl; Hosseini-Bandegharaei, Ahmad; Hosseini, Seyyed-Hossein; Kharghani, Keivan; Zarei, Hossein; Rastegar, Ayoob

    2015-04-01

    In this work, the removal of uranium and thorium ions from aqueous solutions was studied by solid-liquid extraction using an advantageous extractant-impregnated resin (EIR) prepared by loading carminic acid (CA) onto Amberlite XAD-16 resin beads. Batch sorption experiments using CA/XAD-16 beads for the removal of U(VI) and Th(IV) ions were carried out as a function of several parameters, like equilibration time, metal ion concentration, etc. The equilibrium data obtained from the sorption experiments were adjusted to the Langmuir isotherm model and the calculated maximum sorption capacities in terms of monolayer sorption were in agreement with those obtained from the experiments. The experimental data on the sorption behavior of both metal ions onto the EIR beads fitted well in both Bangham and intra-particle diffusion kinetic models, indicating that the intra-particle diffusion is the rate-controlling step. The thermodynamic studies at different temperatures revealed the feasibility and the spontaneous nature of the sorption process for both uranium and thorium ions. PMID:25576783

  5. Organic Chemicals: Angels or Goblins?

    ERIC Educational Resources Information Center

    Ferguson, Lloyd N.

    1978-01-01

    Discusses some of the controversial organic chemical substances such as DDT, Red Dye No. 2, DES, Tris, Laetrile, cyclamate, and saccharin. Concludes that the use of some has to be considered on a benefit/risk ratio. (GA)

  6. Whole-cell fungal transformation of precursors into dyes

    PubMed Central

    2010-01-01

    Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25). Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid) into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other commercially important products. The use of immobilized fungal biomass limits free migration of cells and facilitates their reuse in a continuous system for precursor transformation. PMID:20598166

  7. 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.

  8. Structure, Dynamic and Photophysical Properties of a Fluorescent Dye Incorporated in an Amorphous Hydrophobic Polymer Bundle

    PubMed Central

    De Mitri, N.; Monti, S.; Barone, V.

    2015-01-01

    The properties of a low molecular weight organic dye, namely 4-naphtoyloxy-1-methoxy-2,2,6,6-tetramethylpiperidine, covalently bound to an apolar polyolefin are investigated by means of a multi-level approach, combining classical molecular dynamics simulations, based on an purposely parameterized force fields, and quantum mechanical calculations, based on density functional theory (DFT) and its time-dependent extension (TD-DFT). The structure and dynamics of the dye in its embedding medium is analyzed and discussed in the light of the entangling effect of the surrounding polymer, also by comparing it to the results obtained for a different environment, i.e. toluene solution. The influence on photophysical properties of long lived cages, found in the polymeric embedding is eventually investigated in terms of slow and fast dye’s internal dynamics, by comparing computed IR and UV spectra with their experimental counterparts. PMID:24988373

  9. Secondary dye testing of the lacrimal system.

    PubMed

    Becker, B B

    1993-02-01

    Using the Olympus PF-22 angioscope to examine the inferior meatus during secondary dye testing of the lacrimal system, I evaluated the efficacy of the secondary dye test to localize partial or functional obstruction of the upper or lower lacrimal excretory system. Secondary dye testing was positive (dye present in the nose) in 12 of 13 lacrimal systems (92%) with functional nasolacrimal duct obstruction, in 7 of 8 (89%) with involutional ectropion, and in 4 of 5 (80%) with facial nerve palsy. Secondary dye testing was negative in the 1 lacrimal system with canalicular stenosis and in 5 of the 6 (83%) with punctal stenosis. Secondary dye testing is helpful in differentiating punctal or canalicular stenosis from functional nasolacrimal duct obstruction; however, it cannot help differentiate ectropion or facial nerve palsy from functional nasolacrimal duct obstruction. PMID:8446360

  10. Grating cavity dual wavelength dye laser.

    PubMed

    Zapata-Nava, Oscar Javier; Rodríguez-Montero, Ponciano; Iturbe-Castillo, M David; Treviño-Palacios, Carlos Gerardo

    2011-02-14

    We report simultaneous dual wavelength dye laser emission using Littman-Metcalf and Littrow cavity configurations with minimum cavity elements. Dual wavelength operation is obtained by laser operation in two optical paths inside the cavity, one of which uses reflection in the circulating dye cell. Styryl 14 laser dye operating in the 910 nm to 960 nm was used in a 15%:85% PC/EG solvent green pumped with a Q-switched doubled Nd3+:YAG laser. PMID:21369171

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

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

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

  12. Interactions of small molecules with phospholipid bilayers. Binding to egg phosphatidylcholine of some organic anions (bromosulphophthalein, oestrone sulphate, haem and bilirubin) that bind to ligandin and aminoazo-dye-binding protein A.

    PubMed Central

    Tipping, E; Ketterer, B; Christodoulides, L

    1979-01-01

    1. To assess the possible involvement of ligandin and aminoazo-dye-binding protein A in intracellular transport it is necessary to know how their ligands, most of which are molecules with hydrophobic moieties, interact with cellular membranes. To obtain such information we examined the interactions of bromosulphophthalein, oestrone sulphate, haem and bilirubin with aqueous dispersions of egg phosphatidylcholine and egg phosphatidylchone/cholesterol (1:1, molar ratio) by equilibrium dialysis and spectrophotometry. 2. In all four cases, saturation effects were observed. Values of Vmax (v = mol of compound bound/mol of lipid phosphorus) at 25 degrees C were: for bromosulphophthalein, approximately 0.1; for oestrone sulphate, approximately 0.25; for haem, approximately 0.25 (all at pH 7.4); and for bilirubin 0.1--0.2 (at pH 8.2). 3. Limiting values of v/c (c = unbound concentration) as v leads to 0 at 25 degrees C and pH 7.4 are: for bromosulphophthalein, 6.25 x 10(4) litre-mol-1; for oestrone sulphate, 7.8 x 10(2) litre-mol-1; for haem, 4.5 x 10(5) litre-mol-1; and for bilirubin, approximately 1.2 x 10(4) litre-mol-1. For haem the result depends on the assumption that only the monomeric form binds to the lipid. 4. The binding of each compound was decreased by cholesterol; bromosulphophthalein and oestrone sulphate were affected more than haem and bilirubin. 5. Bromosulphophthalein at saturating concentration decreased the limiting values of v/c of the other three compounds by approximately one order of magnitude. 6. By assuming that the interactions with egg phosphatidylcholine resemble those with the phospholipid components of mammalian intracellular membranes the binding data for phosphyatidylcholine, together with data for binding to the intracellular proteins ligandin and aminoazo-dye-binding protein A, enable the subcellular distributions of the four compounds to be estimated. For the rat hepatocyte up to 92, 51, 98 and 47% of the total bromosulphophthalein, oestrone sulphate, haem and bilirubin respectively may be membrane-bound. PMID:39548

  13. Concrete Embedded Dye-Synthesized Photovoltaic Solar Cell

    PubMed Central

    Hosseini, T.; Flores-Vivian, I.; Sobolev, K.; Kouklin, N.

    2013-01-01

    This work presents the concept of a monolithic concrete-integrated dye-synthesized photovoltaic solar cell for optical-to-electrical energy conversion and on-site power generation. The transport measurements carried out in the dark revealed the presence of VOC of ~190?mV and ISC of ~9??A, induced by the electrochemical conversion of concrete-supplied ionic impurities at the electrodes. The current-voltage measurements performed under illumination at incident optical powers of ~46?mW confirmed the generation of electrical power of ~0.64??W with almost half generated via battery effect. This work presents a first step towards realizing the additional pathways to low-cost electrical power production in urban environments based on a combined use of organic dyes, nanotitania and concrete technology. PMID:24067664

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

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

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

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

    PubMed

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

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (?) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs. PMID:23832227

  16. 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.

  17. Phytoremediation of textile dyes and effluents: Current scenario and future prospects.

    PubMed

    Khandare, Rahul V; Govindwar, Sanjay P

    2015-12-01

    Phytoremediation has emerged as a green, passive, solar energy driven and cost effective approach for environmental cleanup when compared to physico-chemical and even other biological methods. Textile dyes and effluents are condemned as one of the worst polluters of our precious water bodies and soils. They are well known mutagenic, carcinogenic, allergic and cytotoxic agents posing threats to all life forms. Plant based treatment of textile dyes is relatively new and hitherto has remained an unexplored area of research. Use of macrophytes like Phragmites australis and Rheum rhabarbarum have shown efficient removal of Acid Orange 7 and sulfonated anthraquinones, respectively. Common garden and ornamental plants namely Aster amellus, Portulaca grandiflora, Zinnia angustifolia, Petunia grandiflora, Glandularia pulchella, many ferns and aquatic plants have also been advocated for their dye degradation potential. Plant tissue cultures like suspension cells of Blumea malcolmii and Nopalea cochenillifera, hairy roots of Brassica juncea and Tagetes patula and whole plants of several other species have confirmed their role in dye degradation. Plants' oxidoreductases such as lignin peroxidase, laccase, tyrosinase, azo reductase, veratryl alcohol oxidase, riboflavin reductase and dichlorophenolindophenol reductase are known as key biodegrading enzymes which break the complex structures of dyes. Schematic metabolic pathways of degradation of different dyes and their environmental fates have also been proposed. Degradation products of dyes and their fates of metabolism have been reported to be validated by UV-vis spectrophotometry, high performance liquid chromatography, high performance thin layer chromatography, Fourier Transform Infrared Spectroscopy, gas chromatograph-mass spectroscopy and several other analytical tools. Constructed wetlands and various pilots scale reactors were developed independently using the plants of P. australis, Portulaca grandiflora, G. pulchella, Typha domingensis, Pogonatherum crinitum and Alternanthera philoxeroides. The developed phytoreactors gave noteworthy treatments, and significant reductions in biological oxygen demand, chemical oxygen demand, American Dye Manufacturers Institute color removal value, total organic carbon, total dissolved solids, total suspended solids, turbidity and conductivity of the dye effluents after phytoremediation. Metabolites of dyes and effluents have been assayed for phytotoxicity, cytotoxicity, genotoxicity and animal toxicity and were proved to be non/less toxic than untreated compounds. Effective strategies to handle fluctuating dye load and hydraulics for in situ treatment needs scientific attention. Future studies on development of transgenic plants for efficacious phytodegradation of textile dyes should be focused. PMID:26386310

  18. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Dye and chemical solution stains. 864...DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains...

  19. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Dye and chemical solution stains. 864...DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains...

  20. Dye lasers. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Cavagnaro, D. M.

    1980-08-01

    Studies on dye laser theory, design, components, optical systems, and frequency range are presented in approximately 96 citations. Abstracts on lasing dyes, pumping, tuning, excitation, molecular structure, and modulation are included. Studies on dye laser use in spectroscopy are covered.

  1. Investigation of effect of anti-aggregation agent on the performance of nanostructure dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hosseinnezhad, M.; Moradian, S.; Gharanjig, K.

    2015-06-01

    Dye sensitized solar cells (DSSCs) based on indigo dyes exhibit suitable conversion efficiency. These organic dyes have been undergone for aggregation. Electron transfer process is reduced due to an aggregation of molecular dyes. Therefore, anti-aggregation agent is commonly utilized in fabrication of DSSCs. In the present study, two anti-aggregation agents namely as 3?,7?-dihydroxy-5?-cholanic acid (cheno) and 3?,7?,12?-trihydroxy-5?-cholanic acid (cholic acid) were added to indigo dye solution in DSSCs in order to determine the photovoltaic parameters such as short circuit photocurrent, open circuit voltage and conversion efficiency of each individual dye in the absence and presence of anti-aggregation agents. The results show that the conversion efficiencies are improved with reduced aggregation. Spectrophotometric evaluations of the indigo dyes in solution and on a TiO2 substrate were carried out in the absence and presence of anti-aggregation agents in order to estimate changes in the status of the dyes in different environments. J-type aggregates on the nano TiO2 are reduced in the presence of anti-aggregation agents.

  2. Color Tuning of an Acidic Blue Dye by Intercalation into the Basic Interlayer Galleries of a Poly(allylamine)/Synthetic Fluoromica

    E-print Network

    conjugated system and a free sulfonate group. Introduction Many organic dyes are used in the food, cosmetics and hydroxide. For food, medical, and cosmetics applications, however, only certain acidic dyes for cosmetics, the use is strictly restricted by the Pollutant Release and Transfer Register (PRTR

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

    NASA Astrophysics Data System (ADS)

    Furukawa, Shoji; Iino, Hiroshi; Kukita, Koudai; Kaminosono, Kaoru

    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 point larger than that of the solar cell fabricated using red-cabbage dye with a pH of 4.0. It was also found that the conversion efficiency of the solar cell fabricated using red-perilla dye with a pH of 3.1 was 0.10 point larger than that of the solar cell fabricated using red-perilla dye with a pH of 5.8. The results are discussed on the bases of the molecular structure of mainly contained dye and the optical absorption spectra.

  4. 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.

  5. Molecular cloning and expression of glutathione S-transferases involved in propargite resistance of the carmine spider mite, Tetranychus cinnabarinus (Boisduval).

    PubMed

    Luo, Yan-Jie; Yang, Zhen-Guo; Xie, Dao-Yan; Ding, Wei; Da, Ai-Si; Ni, Jing; Chai, Jian-Ping; Huang, Ping; Jiang, Xiu-Jun; Li, Shao-Xiang

    2014-09-01

    The carmine spider mite (CSM) Tetranychus cinnabarinus has become a serious pest in China and has developed resistance to acaricide propargite as it is used to control mites worldwide including T. cinnabarinus. In this study, a resistant colony of T. cinnabarinus, PRR34 (37.78-fold resistant ratio), was established after 34 generations of propargite selection, and cross-resistance patterns of 7 other acaricides were determined in comparison with a susceptible strain (SS). The contribution of detoxification enzymes to propargite tolerance were investigated using biological, biochemical and molecular approaches. Enzyme inhibitor synergist tests suggested glutathione S-transferases (GST) involvement in propargite-resistance of PRR34, and GST activity against 1-chloro-2,4-dinitrobenzene (CDNB) was correlated with the development of resistance. Eight novel GST genes (TcGSTd1, TcGSTd2, TcGSTm1, TcGSTm2, TcGSTm3, TcGSTm4 and TcGSTm5) were cloned, and phylogenetic analysis showed that the eight GST genes were most closely related to GST family delta and mu from Tetranychusurticae. Quantitative RT-PCR revealed that the expression level of GSTs in PPR34 strain increased in larvae, nymphs and adults, while decreased in eggs compared with that of SS. Collectively, these results support a role of GSTs in mediating resistance to propargite in the PRR34 strain. TcGSTd1,TcGSTd2 and TcGSTm2 genes might play significant roles in propargite resistance of CSM, especially at adult stage. This is the first attempt to define specific genes involved in GST mediated propargite resistance of T. cinnabarinus at the transcriptional level. PMID:25175649

  6. Analysis of Insecticide Resistance-Related Genes of the Carmine Spider Mite Tetranychus cinnabarinus Based on a De Novo Assembled Transcriptome

    PubMed Central

    Liu, Yanchao; Liu, Xing; Chen, Qiushuang; Peng, Miao; Wang, Xiangzun; Shen, Guangmao; He, Lin

    2014-01-01

    The carmine spider mite (CSM), Tetranychus cinnabarinus, is an important pest mite in agriculture, because it can develop insecticide resistance easily. To gain valuable gene information and molecular basis for the future insecticide resistance study of CSM, the first transcriptome analysis of CSM was conducted. A total of 45,016 contigs and 25,519 unigenes were generated from the de novo transcriptome assembly, and 15,167 unigenes were annotated via BLAST querying against current databases, including nr, SwissProt, the Clusters of Orthologous Groups (COGs), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO). Aligning the transcript to Tetranychus urticae genome, the 19255 (75.45%) of the transcripts had significant (e-value <10?5) matches to T. urticae DNA genome, 19111 sequences matched to T. urticae proteome with an average protein length coverage of 42.55%. Core Eukaryotic Genes Mapping Approach (CEGMA) analysis identified 435 core eukaryotic genes (CEGs) in the CSM dataset corresponding to 95% coverage. Ten gene categories that relate to insecticide resistance in arthropod were generated from CSM transcriptome, including 53 P450-, 22 GSTs-, 23 CarEs-, 1 AChE-, 7 GluCls-, 9 nAChRs-, 8 GABA receptor-, 1 sodium channel-, 6 ATPase- and 12 Cyt b genes. We developed significant molecular resources for T. cinnabarinus putatively involved in insecticide resistance. The transcriptome assembly analysis will significantly facilitate our study on the mechanism of adapting environmental stress (including insecticide) in CSM at the molecular level, and will be very important for developing new control strategies against this pest mite. PMID:24830288

  7. Effect of single walled carbon nanotubes on the threshold voltage of dye based photovoltaic devices

    NASA Astrophysics Data System (ADS)

    Chakraborty, S.; Manik, N. B.

    2016-01-01

    Carbon nanotubes are being widely used in organic photovoltaic (OPV) devices as their usage has been reported to enhance the device efficiency along with other related parameters. In this work we have studied the energy (Ec) effect of single walled carbon nanotubes (SWCNT) on the threshold voltage (Vth) and also on the trap states of dye based photovoltaic devices. SWCNT is added in a series of dyes such as Rose Bengal (RB), Methyl Red (MR), Malachite Green (MG) and Crystal Violet (CV). By analysing the steady state dark current-voltage (I-V) characteristics Vth and Ec is estimated for the different devices with and without addition of SWCNT. It is observed that on an average for all the dyes Vth is reduced by about 30% in presence of SWCNT. The trap energy Ec also reduces in case of all the dyes. The relation between Vth, Ec and total trap density is discussed. From the photovoltaic measurements it is seen that the different photovoltaic parameters change with addition of SWCNT to the dye based devices. Both the short circuit current density and fill factor are found to increase for all the dye based devices in presence of SWCNT.

  8. Ternary bulk heterojunction solar cells: addition of soluble NIR dyes for photocurrent generation beyond 800 nm.

    PubMed

    Lim, Bogyu; Bloking, Jason T; Ponec, Andrew; McGehee, Michael D; Sellinger, Alan

    2014-05-14

    The incorporation of a tert-butyl-functionalized silicon 2,3-naphthalocyanine bis(trihexylsilyloxide) dye molecule as a third component in a ternary blend bulk heterojunction (BHJ) organic solar cell containing P3HT (donor) and PC60BM (acceptor) results in increased NIR absorption. This absorption yields an increase of up to 40% in the short-circuit current and up to 19% in the power conversion efficiency (PCE) in photovoltaic devices. Two-dimensional grazing incidence wide-angle X-ray scattering (2-D GIWAXS) experiments show that compared to the unfunctionalized dye the tert-butyl functionalization enables an increase in the volume fraction of the dye molecule that can be incorporated before the device performance decreases. Quantum efficiency and absorption spectra also indicate that, at dye concentrations above about 8 wt %, there is an approximately 30 nm red shift in the main silicon naphthalocyanine absorption peak, allowing further dye addition to contribute to added photocurrent. This peak shift is not observed in blends with unfunctionalized dye molecules, however. This simple approach of using ternary blends may be generally applicable for use in other unoptimized BHJ systems towards increasing PCEs beyond current levels. Furthermore, this may offer a new approach towards OPVs that absorb NIR photons without having to design, synthesize, and purify complicated donor-acceptor polymers. PMID:24755205

  9. Kinetic study of electro-Fenton oxidation of azo dyes on boron-doped diamond electrode.

    PubMed

    Almomani, Fares; Baranova, Elena A

    2013-01-01

    The present work compares electrochemical degradation of red and blue azo textile dyes in single- and two-compartment electrochemical cells in the presence of Fenton reagent (Fe2+) and using a boron-doped diamond anode. Degradation of both dyes was related to the concentration of dye, applied current density and the concentration of FeSO4 catalyst. Complete colour removal and approximately 91% of organic matter oxidation was achieved in a two-compartment electrochemical cell at an applied current density of 20 mA x cm(-2), pH of 3 and Fe(2+) ion concentration of 0.02 mM. Higher current density and reaction time were required to achieve the same removals in a one-compartment electrochemical cell. Dye degradation kinetics as well as chemical oxygen demand removal rate were successfully modelled to pseudo first-order kinetics. The apparent first-order rate constants (k(o)) for degradation of red dye with an initial concentration of 20, 40 and 60 ppm were found to be 2.67 +/- 0.16, 2.19 +/- 0.09 and 1.5 +/- 0.03 min(-1), and for blue dye at the same initial concentrations were 1.99 +/- 0.2, 0.95 +/- 0.02 and 0.71 +/- 0.030 min(-1), respectively. PMID:24191481

  10. Decolourisation of dyes under electro-Fenton process using Fe alginate gel beads.

    PubMed

    Rosales, E; Iglesias, O; Pazos, M; Sanromán, M A

    2012-04-30

    This study focuses on the application of electro-Fenton technique by use of catalytic activity of Fe alginate gel beads for the remediation of wastewater contaminated with synthetic dyes. The Fe alginate gel beads were evaluated for decolourisation of two typical dyes, Lissamine Green B and Azure B under electro-Fenton process. After characterization of Fe alginate gel beads, the pH effect on the process with Fe alginate beads and a comparative study of the electro-Fenton process with free Fe and Fe alginate bead was done. The results showed that the use of Fe alginate beads increases the efficiency of the process; moreover the developed particles show a physical integrity in a wide range of pH (2-8). Around 98-100% of dye decolourisation was obtained for both dyes by electro-Fenton process in successive batches. Therefore, the process was performed with Fe alginate beads in a bubble continuous reactor. High color removal (87-98%) was attained for both dyes operating at a residence time of 30 min, without operational problems and maintaining particle shapes throughout the oxidation process. Consequently, the stable performance of Fe alginate beads opens promising perspectives for fast and economical treatment of wastewater polluted by dyes or similar organic contaminants. PMID:22381372

  11. 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

  12. Photolysis of smoke dyes on soils

    SciTech Connect

    Adams, R.L. . Environmental Research Lab.); Weber, E.J.; Baughman, G.L. . Environmental Research Lab.)

    1994-06-01

    Photolysis of an azo, a quinophthalone, and several anthraquinone smoke dyes was studied on soil surfaces. Initially, rapid photodegradation of each dye occurred, followed by a period of much slower rate of loss, indicating that the remaining fraction of the dye was photochemically protected. The average mean depths of photolysis ranged from 0.33 to 0.68 mm for outdoor studies and from 0.42 to 0.73 mm for lab studies. The magnitude of the mean depths of photolysis suggests that photo-degradation of the dyes occurs through indirect photochemical processes. Photolysis products for only two of the dyes could be identified. Photolysis of Disperse Red 9 resulted in the formation of 1-aminoanthraquinone, whereas Solvent Yellow 33 photo-degraded to give 2-carboxyquinoline and phthalic anhydride. Reaction mechanisms involving sensitized photo-oxidation by singlet oxygen are consistent with the formation of these reaction products.

  13. Near Field Enhanced Photocurrent Generation in P-type Dye-Sensitized Solar Cells

    PubMed Central

    Xu, Xiaobao; Cui, Jin; Han, Junbo; Zhang, Junpei; Zhang, Yibo; Luan, Lin; Alemu, Getachew; Wang, Zhong; Shen, Yan; Xiong, Dehua; Chen, Wei; Wei, Zhanhua; Yang, Shihe; Hu, Bin; Cheng, Yibing; Wang, Mingkui

    2014-01-01

    Over the past few decades, the field of p-type dye-sensitized solar cell (p-DSSC) devices has undergone tremendous advances, in which Cu-based delafossite nanocrystal is of prime interest. This paper presents an augment of about 87% improvement in photocurrent observed in a particular configuration of organic dye P1 sensitized CuCrO2 delafossite nanocrystal electrode coupled with organic redox shuttle, 1-methy-1H- tetrazole-5-thiolate and its disulfide dimer when Au nanoparticles (NPs, with diameter of about 20?nm) is added into the photocathode, achieving a power convert efficiency of 0.31% (measured under standard AM 1.5?G test conditions). Detailed investigation shows that the local electrical-magnetic field effect, induced by Au NPs among the mesoporous CuCrO2 film, can improve the charge injection efficiency at dye/semiconductor interface, which is responsible for the bulk of the gain in photocurrent. PMID:24492539

  14. Pyronin Y (basic xanthene dye)-bentonite composite: A spectroscopic study

    NASA Astrophysics Data System (ADS)

    Tabak, A.; Kaya, M.; Yilmaz, N.; Meral, K.; Onganer, Y.; Caglar, B.; Sungur, O.

    2014-02-01

    The expansion by 1.43 Angstrom of basal spacing and the shift to higher frequencies of in-plane ring vibrations of the Pyronin Y molecule at 1603 and 1527 cm-1 on the formation of Pyronin Y-bentonite composite exhibited that the dye cations might be oriented as a monolayer form in the interlamellar spacing with aromatic rings parallel to clay layers. Thermal analysis results of this composite compared to those of raw bentonite signified the different outer sphere water entities associated with the replacement of inorganic cations with organic dye cations and the gradual decomposition of the organic molecule in the interlamellar spacing. Thermo-Infrared spectra of Pyronin Y-bentonite sample up to high temperatures showed the thermal stability of the dye-clay composite as a result of the presence of ? interactions. The pore structure characteristics of Pyronin Y-bentonite composite exhibited the increase in the number of mesopores during formation of the composite.

  15. Optical properties of thin merocyanine dye layers for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Dikova, J.; Kitova, S.; Stoyanova, D.; Vasilev, A.; Deligeorgiev, T.; Angelova, S.

    2014-05-01

    The potentiality was studied of our newly synthesized push-pull type merocyanine dye, labeled A1, for use as an electron donating component in solution-processed bulk heterojunction (BHJ) organic solar cells. For the purpose, a soluble n-type fullerene, (6,6)-phenyl C61 butyric acid methyl ester (PCBM), which is currently and in the ear future without an alternative, was chosen as an acceptor. The optical constants (n and k) of thin films obtained by spin coating from solutions in chlorobenzene of A1 and of an A1/PCBM blend were determined by spectrophotometric measurements. Further, an optical simulation of a standard BHJ cell with an active layer of an A1dye/PCMB blend was performed using a transfer-matrix formalism. Thus, the optimum thickness of the active layer was calculated to be about 80 nm, which provides overlapping of the total absorption with the solar spectrum in the broad range 400 nm - 800 nm. Finally, the maximum current density, Jsc, was determined to be 13 mA cm2 assuming that the internal quantum efficiency, IQE, is unity. Comparing the calculated Jsc with data on some advanced small-molecule BHJ devices, the prospects for practical applications of the new merocyanine dye are discussed.

  16. Calibration of Far West Technology (FWT-60) radiachromic dye dosemeters

    SciTech Connect

    Mincher, B.J.; Zaidi, M.K.

    1992-01-01

    Radiachromic dye dosimetry was used to measure kilogray doses absorbed by various liquid samples during gamma-ray exposure in a spent nuclear fuel pool. The source of nuclear fuel was the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL). Calibrations were performed using a {sup 60}Co source and were run on bare dosemeters, as well as on dosemeters which mocked to simulate the samples. These dosemeters were prepared as a dye-impregnated nylon film and are commercially available. When exposed to gamma-ray doses of 0.5 to 200 kGy, a color change occurs which has an optical density proportional to absorbed dose. The difference in the calibration curves demonstrated the importance of irradiation of dosemeters under conditions as close to the actual samples as possible. Since these dosemeters could not be immersed directly in the organic solutions of interest, they were sandwiched between layers of lucite and stainless steel. This simulated the conditions inside an irradiated sample and provides a practical method of measuring absorbed doses. The reproducibility of measurements using the radiachromic dye dosemeters is also shown. 10 refs.

  17. Calibration of Far West Technology (FWT-60) radiachromic dye dosemeters

    SciTech Connect

    Mincher, B.J.; Zaidi, M.K.

    1992-08-01

    Radiachromic dye dosimetry was used to measure kilogray doses absorbed by various liquid samples during gamma-ray exposure in a spent nuclear fuel pool. The source of nuclear fuel was the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory (INEL). Calibrations were performed using a {sup 60}Co source and were run on bare dosemeters, as well as on dosemeters which mocked to simulate the samples. These dosemeters were prepared as a dye-impregnated nylon film and are commercially available. When exposed to gamma-ray doses of 0.5 to 200 kGy, a color change occurs which has an optical density proportional to absorbed dose. The difference in the calibration curves demonstrated the importance of irradiation of dosemeters under conditions as close to the actual samples as possible. Since these dosemeters could not be immersed directly in the organic solutions of interest, they were sandwiched between layers of lucite and stainless steel. This simulated the conditions inside an irradiated sample and provides a practical method of measuring absorbed doses. The reproducibility of measurements using the radiachromic dye dosemeters is also shown. 10 refs.

  18. The self-aggregation of some 7H-indolo[1,2-a]quinolinium dyes in aqueous solution

    NASA Astrophysics Data System (ADS)

    Sawicka, Marta J.

    2015-10-01

    The aggregation of some 7H-indolo[1,2-a]quinolinium dyes in aqueous solution was investigated based on UV-vis spectroscopy. The influence of pH, dye concentration, ionic strength and the addition of organic solvents on the process was studied. The aggregation took place in alkaline solution and was strongly affected by ionic strength and the presence of organic solvents. The existence of aggregates in the solution was manifested in a new band appearance which exhibited bathochromic shift with respect to the monomer band. For all studied dyes the band was assigned to the dimer and the equilibrium constants for dimer formation were calculated. The dye tendency to aggregate was determined by its structure and was enhanced by the presence of naphthalene moiety in comparison to that of benzene ring as well as electron-rich substituents such as halogens.

  19. 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.

  20. DFT and TD-DFT study on geometries, electronic structures and electronic absorption of some metal free dye sensitizers for dye sensitized solar cells.

    PubMed

    Mohr, T; Aroulmoji, V; Ravindran, R Samson; Müller, M; Ranjitha, S; Rajarajan, G; Anbarasan, P M

    2015-01-25

    The geometries, electronic structures, polarizabilities and hyperpolarizabilities of 2-hydroxynaphthalene-1,4-dione (henna1), 3-(5-((1E)-2-(1,4-dihydro-1,4-dioxonaphthalen-3-yloxy) vinyl) thiophen-2-yl)-2-isocyanoacrylic acid (henna2) and anthocyanin dye sensitizers were studied based on density functional theory (DFT) using the hybrid functional B3LYP. The Ultraviolet-Visible (UV-Vis) spectrum was investigated by using a hybrid method which combines the properties and dynamics of many-body in the presence of time-dependent (TD) potentials, i.e. TDSCF-DFT (B3LYP). Features of the electronic absorption spectrum in the visible and near-UV regions were plotted and assigned based on TD-DFT calculations. Due to the absorption, bands of the metal-organic compound are n??(*) present. The calculated results suggest that the three lowest energy excited states of the investigated dye sensitizers are due to photoinduced electron transfer processes. The interfacial electron transfer between semiconductor TiO2 electrode and dye sensitizer is owing to an electron injection process from excited dye to the semiconductor's conduction band. The role of linking the henna1 dye with a carboxylic acid via a thiophene bridge was analyzed. The results are that using a stronger ?-conjugate bridge as well as a strong donator and acceptor group enhances the efficiency. PMID:25173523

  1. Visible-light responsive dye-modified TiO{sub 2} photocatalyst

    SciTech Connect

    Jiang Dong; Xu Yao Wu Dong; Sun Yuhan

    2008-03-15

    A series of dye-modified TiO{sub 2} photocatalysts were synthesized using dye Chrysoidine G (CG), tolylene-2,4-diisocyanate (TDI), and commercial TiO{sub 2} (Degussa P25) as starting materials. TDI was used as a bridging molecule whose two -NCO groups reacted with Ti-OH of TiO{sub 2} and -NH{sub 2} groups of CG, respectively. As a result, special organic complexes were formed on the TiO{sub 2} surface via stable {pi}-conjugated chemical bonds between TiO{sub 2} and dye molecules, confirmed by FT-IR, XPS, and UV-vis spectra. Due to the existence of {pi}-conjugated surface organic complexes, the as-synthesized photocatalysts showed a great improvement in visible absorption (400-550 nm). Methylene blue, as a photodegradation target, was used to evaluate the photocatalytic performance, and the dye-modified TiO{sub 2} exhibited much better activity under the visible light irradiation than bare TiO{sub 2}. - Graphical abstract: Dye-modified TiO{sub 2} photocatalysts were synthesized via the reaction between Chrysoidine G (CG), Degussa P25 (TiO{sub 2}), and tolylene-2,4-diisocyanate (TDI) as a bridging molecule. As a result, {pi}-conjugated surface organic complexes were formed on TiO{sub 2} surface. Due to the existence of organic complexes, dye-modified TiO{sub 2} catalysts showed great visible absorption and high activity under the visible light irradiation.

  2. Interfacial Properties of a Hydrophobic Dye in the Tetrachloroethylene-Water-Glass Systems

    SciTech Connect

    Tuck, D.M.

    1999-02-23

    Interfacial effects play an important role in governing multiphase fluid behavior in porous media. Strongly hydrophobic organic dyes, used in many experimental studies to facilitate visual observation of the phase distributions, have generally been implicitly assumed to have no influence on the interfacial properties of the various phases in porous media. Sudan IV is the most commonly used dye for non-aqueous phase liquids (NAPLs) in laboratory experiments. It has also been used in at least one field experiment. The effects of this dye on the tetrachloroethylene (PCE)-water-glass system were investigated to test the assumption that the dye does not effect the interfacial properties and therefore PCE mobility. The results indicate that the dye does indeed change the interfacial relationships.The effect of the dye on the interfacial relationships is a complex function of the dye concentration, the solid phase composition, and the dynamic rate of new interface formation. The dye caused a slight (<10 percent) increase in interfacial tension at low concentrations (<0.1 g/L) and high rates of new interface formation. The dye reduced interfacial tension between PCE and water at low rates of new interface formation for all dye concentrations tested (0.00508 to 5.08 g/L). At the highest dye concentration, the PCE-water interfacial tension was significantly reduced regardless of the rate of new interface formation. The apparent interfacial tension increase at low dye concentrations is suspected to be an artifact of a low measured IFT value for the undyed PCE caused by leaching of rubber o-rings by the PCE prior to testing in the final drop-volume configuration.In addition to reducing interfacial tension, the dye was found to significantly alter the wetting relationship between PCE and water on a glass surface at and above the range of reported dye concentrations cited in the literature (1.1 to 1.7 g/L). The wetting relationship was rendered neutral from a water-wet initial condition at the highest dye concentration. The contact angle, measured through the aqueous phase, changed from 58 degrees for undyed PCE to 93 degrees at a dye concentration of 5.08 g/L. Complete reversal of the wettability is likely given the short equilibration time used in this study (approximately five minutes) together with literature indications that hundreds to thousands of hours may be required to reach equilibrium during contact angle measurements. Observations suggesting changing wetting relationships were also noted between PCE, water, and the platinum-iridium surface used in the standard du No/374y ring method for measuring interfacial tension.Observations of the dyed-PCE-water interface behavior during du No/374y ring interfacial tension measurements were similar to observations noted previously during measurements of the interfacial tension between the Savannah River Site (SRS) M-Area Settling Basin DNAPL (M-Area DNAPL) and water. This observation suggests that the M-Area DNAPL may contain surface active components. If this proves to be the case, it would have significant implications for how the M-Area DNAPL is distributed and moves in the SRS subsurface.

  3. Shock wave diagnostics using fluorescent dye probes

    NASA Astrophysics Data System (ADS)

    Banishev, Alexandr; Christensen, James; Dlott, Dana

    2015-06-01

    Fluorescent probes are highly developed, and have found increasing use in a wide variety of applications. We have studied shock compression of various materials with embedded dye probes used as high speed probes of pressure and temperature. Under the right conditions, dye emission can be used to make a map of the pressure distribution in shocked microstructured materials with high time (1 ns) and space (1 micrometer) resolution. In order to accomplish this goal, we started by studying shock compression of PMMA polymer with rhodamine 6G dye (R6G), as a function of shock pressure and shock duration. We observed the shock-induced spectral redshift and the shock-induced intensity loss. We investigated the fundamental mechanisms of R6G response to pressure. We showed that the time response of a dye probe is limited by its photophysical behavior under shock. We developed superemissive ultrafast dye probes by embedding R6G in a silica nanoparticle. More recently, we have searched for dye probes that have better responses. For instance, we have found that the dye Nile Red embedded in the right polymer matrix has 1.7 times larger pressure-induced redshift than R6G.

  4. Hierarchically Structured Zn2SnO4 Nanobeads for High-Efficiency Dye-Sensitized Solar Cells

    PubMed Central

    Hwang, Daesub; Jin, Jun-Su; Lee, Horim; Kim, Hae-Jin; Chung, Heejae; Kim, Dong Young; Jang, Sung-Yeon; Kim, Dongho

    2014-01-01

    We developed a unique strategy for fabricating hierarchically structured (nanoparticles-in-beads) Zn2SnO4 beads (ZTO-Bs), which were then used to produce ternary metal oxide-based dye-sensitized solar cells (DSSCs). DSSCs were fabricated using the ZTO-Bs as the photoelectrodes and highly absorbable organic dyes as the sensitizers. The DSSCs based on the ZTO-Bs and the organic dyes (SJ-E1 and SJ-ET1) exhibited the highest performance ever reported for DSSCs with ternary metal oxide-based photoelectrodes. The optimized DSSCs exhibited a power conversion efficiency of 6.3% (VOC of 0.71?V, JSC of 12.2?mA cm?2, FF of 0.72), which was much higher than that for DSSCs with conventional ZTO-NPs-based photoelectrodes or those based on the popular ruthenium-based dye, N719. The unique morphology of the ZTO-Bs allowed for improvements in dye absorption, light scattering, electrolyte penetration, and the charge recombination lifetime, while the organic dyes resulted in high molar absorbability. PMID:25483243

  5. Ultrasound energy to accelerate dye uptake and dye-fiber interaction of reactive dye on knitted cotton fabric at low temperatures.

    PubMed

    Tissera, Nadeeka D; Wijesena, Ruchira N; de Silva, K M Nalin

    2016-03-01

    Acoustic cavitation formed due to propagation of ultrasound wave inside a dye bath was successfully used to dye cotton fabric with a reactive dye at lower temperatures. The energy input to the system during sonication was 0.7W/cm(2). This was within the energy range that contributes towards forming cavitation during ultra-sonication. The influence of ultrasound treatment on dye particle size and fiber morphology is discussed. Particle size analysis of the dye bath revealed ultra-sonication energy was capable of de-agglomeration of hydrolyzed dye molecules during dyeing. SEM micrograph and AFM topographical image of the fiber surface revealed fiber morphology remains unchanged after the sonication. The study was extended in understanding the contribution of ultrasound method of dyeing towards achieving good color strength on the fabric, compared to the normal heating method of dyeing. Study showed color strength obtained using ultra sound method of dyeing is higher compared to normal heating dyeing. Ultrasound energy was able to achieve the good color strength on cotton fabric at very low temperature such as 30°C, which was approximately 230% more than the color strength achieved in normal heating method of dyeing. This indicates that energy input to the system using ultrasound was capable of acting as an effective alternative method of dyeing knitted cotton fabrics with reactive dye. PMID:26585007

  6. Biology of the Blues: The Snails behind the Ancient Dyes

    NASA Astrophysics Data System (ADS)

    Steinhart, Carol

    2001-11-01

    Three species of marine snails were used in the ancient Mediterranean dye industry. Colorless dye precursors, sulfur-containing indole derivatives, are secreted by the hypobranchial gland of these animals. The several functions of this gland and other aspects of the lives of the snails that are interesting and relevant to the dye industry are described and the chemistry of dye production is summarized.

  7. A luminescent dye@MOF as a dual-emitting platform for sensing explosives.

    PubMed

    Hu, Xiao-Li; Qin, Chao; Wang, Xin-Long; Shao, Kui-Zhan; Su, Zhong-Min

    2015-12-01

    An anionic metal-organic framework (MOF) with 1D nanotube channels has been constructed. The charge and size dependent ion-exchange of cationic dyes was investigated. Rho@1 could be used as a dual-emitting fluorescent sensor for sensing explosives by self-referencing energy transfer behaviors. PMID:26434916

  8. Synthesis of Triarylmethane and Xanthene Dyes Using Electrophilic Aromatic Substitution Reactions

    ERIC Educational Resources Information Center

    McCullagh, James V.; Daggett, Kelly A.

    2007-01-01

    The synthesis of dyes has long been a popular topic in organic chemistry laboratory experiments because it allows students to see first hand that reactions learned in class can be used to make compounds with useful applications. In this experiment electrophilic aromatic substitution reactions are used to synthesize several triarylmethane and…

  9. Dye Degradation by Fungi: An Exercise in Applied Science for Biology Students

    ERIC Educational Resources Information Center

    Lefebvre, Daniel D.; Chenaux, Peter; Edwards, Maureen

    2005-01-01

    An easily implemented practical exercise in applied science for biology students is presented that uses fungi to degrade an azo-dye. This is an example of bioremediation, the employment of living organisms to detoxify or contain pollutants. Its interdisciplinary nature widens students' perspectives of biology by exposing them to a chemical…

  10. Improved Charge-Transfer Fluorescent Dyes

    NASA Technical Reports Server (NTRS)

    Meador, Michael

    2005-01-01

    Improved charge-transfer fluorescent dyes have been developed for use as molecular probes. These dyes are based on benzofuran nuclei with attached phenyl groups substituted with, variously, electron donors, electron acceptors, or combinations of donors and acceptors. Optionally, these dyes could be incorporated as parts of polymer backbones or as pendant groups or attached to certain surfaces via self-assembly-based methods. These dyes exhibit high fluorescence quantum yields -- ranging from 0.2 to 0.98, depending upon solvents and chemical structures. The wavelengths, quantum yields, intensities, and lifetimes of the fluorescence emitted by these dyes vary with (and, hence, can be used as indicators of) the polarities of solvents in which they are dissolved: In solvents of increasing polarity, fluorescence spectra shift to longer wavelengths, fluorescence quantum yields decrease, and fluorescence lifetimes increase. The wavelengths, quantum yields, intensities, and lifetimes are also expected to be sensitive to viscosities and/or glass-transition temperatures. Some chemical species -- especially amines, amino acids, and metal ions -- quench the fluorescence of these dyes, with consequent reductions in intensities, quantum yields, and lifetimes. As a result, the dyes can be used to detect these species. Another useful characteristic of these dyes is a capability for both two-photon and one-photon absorption. Typically, these dyes absorb single photons in the ultraviolet region of the spectrum (wavelengths < 400 nm) and emit photons in the long-wavelength ultraviolet, visible, and, when dissolved in some solvents, near-infrared regions. In addition, these dyes can be excited by two-photon absorption at near-infrared wavelengths (600 to 800 nm) to produce fluorescence spectra identical to those obtained in response to excitation by single photons at half the corresponding wavelengths (300 to 400 nm). While many prior fluorescent dyes exhibit high quantum yields, solvent-polarity- dependent fluorescence behavior, susceptibility to quenching by certain chemical species, and/or two-photon fluorescence, none of them has the combination of all of these attributes. Because the present dyes do have all of these attributes, they have potential utility as molecular probes in a variety of applications. Examples include (1) monitoring curing and deterioration of polymers; (2) monitoring protein expression; (3) high-throughput screening of drugs; (4) monitoring such chemical species as glucose, amines, amino acids, and metal ions; and (5) photodynamic therapy of cancers and other diseases.

  11. Quirks of dye nomenclature. 5. Rhodamines.

    PubMed

    Cooksey, C J

    2016-01-01

    Rhodamines were first produced in the late 19(th) century, when they constituted a new class of synthetic dyes. These compounds since have been used to color many things including cosmetics, inks, textiles, and in some countries, food products. Certain rhodamine dyes also have been used to stain biological specimens and currently are widely used as fluorescent probes for mitochondria in living cells. The early history and current biological applications are sketched briefly and an account of the ambiguities, complications and confusions concerning dye identification and nomenclature are discussed. PMID:26529223

  12. Near?infrared fluorescence imaging of prostate cancer using heptamethine carbocyanine dyes.

    PubMed

    Yuan, Jianlin; Yi, Xiaomin; Yan, Fei; Wang, Fuli; Qin, Weijun; Wu, Guojun; Yang, Xiaojian; Shao, Chen; Chung, Leland W K

    2015-02-01

    Near?infrared fluorescence (NIRF) imaging is an attractive novel modality for the detection of cancer. A previous study defined two organic polymethine cyanine dyes as ideal NIRF probes, IR?783 and its derivative MHI?148, which have excellent optical characteristics, superior biocompatibility and cancer targeting abilities. To investigate the feasibility of NIRF dye?mediated prostate cancer imaging, dye uptake and subcellular co?localization were investigated in PC?3, DU?145 and LNCaP human prostate cancer cells and RWPE?1 normal prostate epithelial cells. Different organic anion transporting peptide (OATP) inhibitors were utilized to explore the potential role of the OATP subtype, including the nonspecific OATP inhibitor bromosulfophthalein, the OATP1 inhibitor 17??estradiol, the selective OATP1B1 inhibitor rifampicin and the selective OATP1B3 inhibitor cholecystokinin octapeptide. NIRF dyes were also used for the simulated detection of circulating tumor cells and the rapid detection of prostate cancer in human prostate cancer tissues and prostate cancer xenografts in mouse models. The results revealed that the cancer?specific uptake of these organic dyes in prostate cancer cells occurred primarily via OATP1B3. A strong NIRF signal was detected in prostate cancer tissues, but not in normal tissues that were stained with IR?783. Prostate cancer cells were recognized with particular NIR fluorescence in isolated mononuclear cell mixtures. The results of the present study demonstrated that NIRF dye?mediated imaging is a feasible and practicable method for prostate cancer detection, although further investigative studies are required before clinical translation. PMID:25354708

  13. Natural Dye Extracted from Vitex negundo as a Potential Alternative to Synthetic Dyes for Dyeing of Silk

    NASA Astrophysics Data System (ADS)

    Narayana Swamy, Venkataramanappa; Gowda, Kurikempanadoddi Ninge; Sudhakar, Rajagopal

    2015-06-01

    Since the last decade, the application of natural dyes on textile material has been gaining popularity all over the world, possibly because of the increasing awareness of issues concerning the environment, ecology and pollution control. The present paper investigates extraction of natural dye from leaves of the plant Vitex negundo, which is an abundant, cheap, and readily available agricultural by-product. Water extracts from V. negundo was used to dye silk fabrics. Optimum extraction conditions included pH 9, duration 120 min, and temperature 90 °C. Optimum dyeing conditions included dyeing pH 5 and duration of 60 min. Potash alum, tannic and tartaric acid were used as mordants, all of which are benign to human health and the environment. Color strength and color coordinates in terms of L*, a*, b*, C, and h were examined. A range of shades were obtained when fabrics were dyed with different mordants and mordanting techniques. The extracted dye was tested for some of the eco-parameters using atomic absorption spectrophotometry and GC/MS. The test results were compared with set standards to determine the eco-friendliness of natural dye. Their concentrations were found to be lower than the stipulated limits. Dyed samples were tested for antimicrobial activity against gram-positive and gram-negative bacteria. The dyed silk fabrics showed acceptable fastness properties and were also found to possess antibacterial activity. It can be concluded that the abundantly available agricultural by-product V. negundo has great potential to be effectively utilized as a natural dye for silk.

  14. Effect of Electrolytes on the Decomposition of Dye by Pulsed Discharge in Air Spraying Water Droplets

    NASA Astrophysics Data System (ADS)

    Nose, Taisuke; Yokoyama, Yuzo; Minamitani, Yasushi

    Effect of electrolytes on the decolorization of indigo carmine and on the production of H2O2 by pulsed discharge in air spraying water droplets was performed in sodium chloride and magnesium sulfate solutions. Peak voltage of the discharge decreased with increasing solution conductivity, but peak current and discharge energy increased. Decolorization rate and decolorization efficiency of indigo carmine and the yield of H2O2 decreased with increasing chloride and sulfate ion concentrations. It was found that the decolorization of indigo carmine and the production of H2O2 are affected by the ion concentration even in the case of discharge in air spraying water droplets. However it was less effective than that of discharge in water. Chloride ion was more effective than sulfate ion regarding the decrease of decolorization rate and the production of H2O2. Decolorization rate of indigo carmine was strongly related to the production of H2O2. These results also indicated that decolorization of indigo carmine depends on the production of hydroxyl radical.

  15. Degradation of sulphonated azo dye Red HE7B by Bacillus sp. and elucidation of degradative pathways.

    PubMed

    Thakur, Jyoti Kumar; Paul, Sangeeta; Dureja, Prem; Annapurna, K; Padaria, Jasdeep C; Gopal, Madhuban

    2014-08-01

    Bacteria capable of degrading the sulfonated azo dye Red HE7B were isolated from textile mill effluent contaminated soil. The most efficient isolate was identified as Bacillus sp. Azo1 and the isolate could successfully decolorize up to 89% of the dye. The decolorized cultural extract analyzed by HPLC confirmed degradation. Enzymatic analysis showed twofold and fourfold increase in the activity of azoreductase and laccase enzymes, respectively, indicating involvement of both reductive and oxidative enzymes in biodegradation of Red HE7B. Degraded products which were identified by GC/MS analysis included various metabolites like 8-nitroso 1-naphthol, 2-diazonium naphthalene. Mono azo dye intermediate was initially generated from the parent molecule. This mono azo dye was further degraded by the organism, into additional products, depending on the site of cleavage of R-N=N-R molecule. Based on the degradation products identified, three different pathways have been proposed. The mechanism of degradation in two of these pathways is different from that of the previously reported pathway for azo dye degradation. This is the first report of a microbial isolate following multiple pathways for azo dye degradation. Azo dye Red HE7B was observed to be phytotoxic, leading to decrease in root development, shoot length and seedling fresh weight. However, after biotreatment the resulting degradation products were non-phytotoxic. PMID:24682261

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

    PubMed Central

    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

  17. 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.

  18. Analysis and Characterization of Dye-Based Black Matrix Film of Low Dielectric Constant Containing Phthalocyanine and Perylene Dyes.

    PubMed

    Lee, Woosung; Choi, Jun; Kim, Se Hun; Park, Jongseung; Kim, Jae Pil

    2015-01-01

    For liquid crystal display black matrices of low dielectric constant, greenish zinc phthalocyanine dye and reddish perylene dye exhibiting high solubility and thermal stability were employed to fabricate dye-based black matrices. The spectral, optical, thermal and dielectric properties of the dye-based black matrices were tested, and the surfaces of them were investigated using field emission scanning electron microscopy and atomic force microscopy. The dye-based black matrices had sufficiently low dielectric constants and showed satisfactory thermal stability and weaker light absorption property compared with black matrices containing carbon black, due to the low solubility of the dyes and dye aggregations after a post-baking process. PMID:26328348

  19. Spontaneous photoinduced patterning of azo-dye polymer films: the facts

    SciTech Connect

    Hubert, Christophe

    2007-08-15

    We describe the spontaneous photoinduced patterning of azo-dye polymer films. We have observed that the illumination of an azo-dye polymer film by a uniform single laser beam with normal incidence leads to a self-structurization process that results in the formation of well-ordered submicrometer-sized structures whose organization depends on the light polarization direction. A modulation depth as high as 100 nm can be achieved. The influence of several experimental parameters on the structure formation is studied. Results are discussed and confronted to different models and phenomena already investigated in the literature. A physical origin to this peculiar photopatterning process is proposed.

  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. Chromosome characterization using single fluorescent dye

    DOEpatents

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

    1995-01-01

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

  2. Polymerization of novel methacrylated anthraquinone dyes

    PubMed Central

    Dollendorf, Christian; Kreth, Susanne Katharina; Choi, Soo Whan

    2013-01-01

    Summary A new series of polymerizable methacrylated anthraquinone dyes has been synthesized by nucleophilic aromatic substitution reactions and subsequent methacrylation. Thereby, green 5,8-bis(4-(2-methacryloxyethyl)phenylamino)-1,4-dihydroxyanthraquinone (2), blue 1,4-bis(4-((2-methacryloxyethyl)oxy)phenylamino)anthraquinone (6) and red 1-((2-methacryloxy-1,1-dimethylethyl)amino)anthraquinone (12), as well as 1-((1,3-dimethacryloxy-2-methylpropan-2-yl)amino)anthraquinone (15) were obtained. By mixing of these brilliant dyes in different ratios and concentrations, a broad color spectrum can be generated. After methacrylation, the monomeric dyes can be covalently emplaced into several copolymers. Due to two polymerizable functionalities, they can act as cross-linking agents. Thus, diffusion out of the polymer can be avoided, which increases the physiological compatibility and makes the dyes promising compounds for medical applications, such as iris implants. PMID:23503994

  3. 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)

  4. Thermal treatment of dyes from military munitions

    SciTech Connect

    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.

  5. Phytoremediation in education: textile dye teaching experiments.

    PubMed

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

    2009-07-01

    Phytoremediation, the use of plants to clean up contaminated soil and water, has a wide range of applications and advantages, and can be extended to scientific education. Phytoremediation of textile dyes can be used as a scientific experiment or demonstration in teaching laboratories of middle school, high school and college students. In the experiments that we developed, students were involved in a hands-on activity where they were able to learn about phytoremediation concepts. Experiments were set up with 20-40 mg L(-1) dye solutions of different colors. Students can be involved in the set up process and may be involved in the experimental design. In its simplest forms, they use two-week-old sunflower seedlings and place them into a test tube of known volume of dye solution. Color change and/or dye disappearance can be monitored by visual comparison or with a spectrophotometer. Intensity and extent of the lab work depends on student's educational level, and time constraints. Among the many dyes tested, Evan's Blue proved to be the most readily decolorized azo dye. Results could be observed within 1-2 hours. From our experience, dye phytoremediation experiments are suitable and easy to understand by both college and middle school students. These experiments help visual learners, as students compare the color of the dye solution before and after the plant application. In general, simple phytoremediation experiments of this kind can be introduced in many classes including biology, biochemistry and ecological engineering. This paper presents success stories of teaching phytoremediation to middle school and college students. PMID:19810348

  6. Corrosion Inhibitors as Penetrant Dyes for Radiography

    NASA Technical Reports Server (NTRS)

    Novak, Howard L.; Hall, Phillip B.

    2003-01-01

    Liquid/vapor-phase corrosion inhibitors (LVCIs) have been found to be additionally useful as penetrant dyes for neutron radiography (and perhaps also x-radiography). Enhancement of radiographic contrasts by use of LVCIs can reveal cracks, corrosion, and other defects that may be undetectable by ultrasonic inspection, that are hidden from direct optical inspection, and/or that are difficult or impossible to detect in radiographs made without dyes.

  7. 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

  8. Exploring ruthenium dye synthesis and TiO2-dye-I-/I3- electron transfer reactions in a dye-sensitised solar cell. 

    E-print Network

    Chadwick, Nina

    2013-11-28

    Octahedral, six co-ordinate ruthenium complexes containing acid substituted polypyridyl ligands have proved particularly successful as dyes for Dye-Sensitised Solar Cells (DSSCs); thus there have been hundreds, if not ...

  9. Modeling opto-electronic properties of a dye molecule in proximity of a semiconductor nanoparticle

    NASA Astrophysics Data System (ADS)

    Delgado, Alain; Corni, Stefano; Goldoni, Guido

    2013-07-01

    A general methodology is presented to model the opto-electronic properties of a dye molecule in the presence of a semiconductor nanoparticle (NP), a model system for the architecture of dye-sensitized solar cells. The method is applied to the L0 organic dye solvated with acetonitrile in the neighborhood of a TiO2 NP. The total reaction potential due to the polarization of the solvent and the metal oxide is calculated by extending the polarizable continuum model integral equation formalism. The ground state energy is computed by using density functional theory (DFT) while the vertical electronic excitations are obtained by time-dependent DFT in a state-specific corrected linear response scheme. We calculate the excited state oxidation potential (ESOP) for the protonated and deprotonated forms of the L0 dye at different distances and configurations with respect to the NP surface. The stronger renormalizations of the ESOP values due to the presence of the TiO2 nanostructure are found for the protonated dye, reaching a maximum of about -0.15 eV. The role of protonation effect is discussed in terms of the atomic Löwdin charges of the oxidized and reduced species. On the other hand, we observed a weak effect on the L0 optical excitation gap due to the polarization response of the NP.

  10. Degradation of dyes by active species injected from a gas phase surface discharge

    NASA Astrophysics Data System (ADS)

    Li, Jie; Wang, Tiecheng; Lu, Na; Zhang, Dandan; Wu, Yan; Wang, Tianwei; Sato, Masayuki

    2011-06-01

    A reactor, based on the traditional gas phase surface discharge (GPSD), is designed for degradation of dye wastewater in this study. The reactor is characterized by using the dye wastewater as a ground electrode. A spiral discharge electrode of stainless steel wire attached on the inside wall of a cylindrical insulating medium and the wastewater surrounding the insulating medium for simultaneous cooling of the discharge electrode constitute the reactor. The active chemical radicals generated by the discharge of the spiral electrode are injected into the water with the carrier gas. The removal of three organic dyes (including methyl red (MR), reactive brilliant blue (RBB) and cationic red (CR)) in aqueous solution is investigated. The effects of electrode configuration, discharge voltage and solution pH value on the decoloration efficiency of MR are discussed. The experimental results show that over 95% of decoloration efficiencies for all the dyes are obtained after several minutes of plasma treatment. 40% of chemical oxygen demand removal of MR is obtained after 8 min of discharge treatment. Furthermore, it is found that ozone mainly affects the removal of dyes and several aliphatic compounds are identified as the oxidation products of MR. The possible degradation pathways of MR by GPSD are proposed.

  11. Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics

    PubMed Central

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

    2014-01-01

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

  12. 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...

  13. 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...

  14. Chlorine disinfection of dye wastewater: implications for a commercial azo dye mixture.

    PubMed

    Vacchi, Francine Inforçato; Albuquerque, Anjaina Fernandes; Vendemiatti, Josiane Aparecida; Morales, Daniel Alexandre; Ormond, Alexandra B; Freeman, Harold S; Zocolo, Guilherme Julião; Zanoni, Maria Valnice Boldrin; Umbuzeiro, Gisela

    2013-01-01

    Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC-ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1. PMID:23178834

  15. Solvatochromism, spectral properties and antimicrobial activities of new azo-azomethine dyes with N2S2O2 donor set of atoms

    NASA Astrophysics Data System (ADS)

    Khanmohammadi, Hamid; Pass, Maryam; Rezaeian, Khatereh; Talei, Gholamreza

    2014-08-01

    Six new azo-azomethine dyes, H2Ln (n = 1-6), with N2S2O2 donor set of atoms have been prepared via condensation reaction of 1,10-diaza-4,7-dithiadecane, I, with substituted azo-coupled salicylaldehyde. The dyes were characterized by IR, UV-Vis and 1H NMR spectroscopic methods as well as elemental analysis. The solvatochromic behavior of the dyes was also probed by studying their UV-Vis spectra in four pure organic solvents of different polarities and a meaningful correlation was observed. Furthermore, all prepared dyes were assayed for their antibacterial and antifungal activities by disc diffusion method. The results indicated that all prepared dyes show good inhibition against Staphylococcus epidermidis and Bacillus cereus and did not show any antibacterial activity against Escherichia coli as compared to standard drugs.

  16. Fiber optics interface for a dye laser oscillator and method

    NASA Astrophysics Data System (ADS)

    Johnson, S. A.; Seppala, L. G.

    1984-06-01

    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 along with a specific arrnagement including an optical fiber and a fibre 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.

  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. Physical and chemical investigations on natural dyes

    NASA Astrophysics Data System (ADS)

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

    2010-09-01

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

  19. Joint electrical, photophysical, and photovoltaic studies on truxene dye-sensitized solar cells: impact of arylamine electron donors.

    PubMed

    Wang, Zhihui; Liang, Mao; Wang, He; Wang, Peng; Cheng, Fangyi; Sun, Zhe; Song, Xue

    2014-03-01

    The judicious design of electron donors is one of the viable tactics to improve the efficiency of organic dyes for dye-sensitized solar cells (DSCs) employing outer-sphere redox couples. Herein, a hexahexyltruxene-substituted 4-(hexyloxy)-N-phenylaniline (HT-HPA) segment is constructed and employed as the electron donor in two organic push-pull dyes (M28 and M29) with high molar absorption coefficient values. Relative to its congener (C241) possessing the dihexyloxy-substituted triphenylamine electron donor, M29 exhibits red-shifted absorption as well as enhanced maximum molar absorption coefficient values. A thorough comparison with M29 and C241 demonstrates that the HT-HPA segment adequately insulates the TiO2 surface from the electrolyte, which prevents back-recombination and prolongs electron lifetime in the semiconductor. The diminishment of charge recombination not only enables attainment of strikingly high photovoltages (approaching 1?V), but also overcompensates the disadvantageous impact of lower dye-load amounts. As a result, the dye transformation from C241 to M29 brings forth an efficiency improvement from 7.3?% to 8.5?% at the 100?mW?cm(-2) simulated AM1.5 conditions. Our work should shed light on the future design of more powerful push-pull organic photosensitizers for iodine-free DSCs. PMID:24493016

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

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

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

    PubMed

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

    2014-07-15

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC. PMID:24682058

  2. Optical properties of dyes affected by accelerating UV light exposure

    NASA Astrophysics Data System (ADS)

    Huang, Der-Ray; Chen, Yi-An; Liou, Run-Lin; Lin, Jing-Xuan; Tsai, Chih-Hung

    2015-09-01

    The optical characteristics of dyes are very important factors either for optical recording media or for dye sensitized solar cells (DSSC). The purpose of this paper is to study the stability of the dye in room temperature under the UV light exposure. Different dyes for different applications have different effect on the optical properties of dyes under the UV light exposures. Generally the dyes for recording media are very sensitive to the UV light exposure, while the dyes for DSSC applications are not so sensitive to the UV light exposure. After UV light exposure for 20-50 h, the intensities of main absorption peaks for recordable media are degraded obviously, while the intensities of main absorption peaks for dye sensitized solar cells are not degraded obviously.

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

    ERIC Educational Resources Information Center

    Markow, Peter G.

    1988-01-01

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

  4. Spectral characteristics and nonlinear studies of crystal violet dye

    NASA Astrophysics Data System (ADS)

    Sukumaran, V. Sindhu; Ramalingam, A.

    2006-03-01

    Solid-state dye-doped polymer is an attractive alternative to the conventional liquid dye solution. In this paper, the spectral characteristics and the nonlinear optical properties of the dye crystal violet are studied. The spectral characteristics of crystal violet dye doped poly(methylmethacrylate) modified with additive n-butyl acetate (nBA) are studied by recording its absorption and fluorescence spectra and the results are compared with the corresponding liquid mixture. The nonlinear refractive index of the dye in nBA and dye doped polymer film were measured using z-scan technique, by exciting with He-Ne laser. The results obtained are intercompared. Both the samples of dye crystal violet show a negative nonlinear refractive index. The origin of optical nonlinearity in the dye may be attributed due to laser-heating induced nonlinear effect.

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

    NASA Astrophysics Data System (ADS)

    Sahmer, Ahmad Zahrin; Mohamed, Norani Muti; Zaine, Siti Nur Azella

    2015-07-01

    Dye sensistised solar cell (DSC) based on nanocrystalline TiO2 has the potential to be used in indoor consumer power application. In realizing this, the DSC must be optimized to generate power under low lighting condition and under wider visible light range. The use of wide band dye N749 which has a wider spectrum sensitivity increases the photon conversion to electron between the visible light spectrums of 390nm to 700nm. This paper reports the study on the effectiveness of the dye solar cell with N749 dye under low light condition in generating usable power which can be used for indoor consumer application. The DSC was fabricated using fluorine doped tin oxide (FTO) glass with screen printing method and the deposited TiO2 film was sintered at 500°C. The TiO2 coated FTO glass was then soaked in the N749 dye, assembled into test cell, and tested under the standard test condition at irradiance of 1000 W/m2 with AM1.5 solar soaker. The use of the 43T mesh for the dual pass screen printing TiO2 paste gives a uniform TiO2 film layer of 16 µm. The low light condition was simulated using 1/3 filtered irradiance with the solar soaker. The fabricated DSC test cell with the N749 dye was found to have a higher efficiency of 6.491% under low light condition compared to the N719 dye. Under the standard test condition at 1 sun the N749 test cell efficiency is 4.55%. The increases in efficiency is attributed to the wider spectral capture of photon of the DSC with N749 dye. Furthermore, the use of N749 dye is more effective under low light condition as the VOC decrement is less significant compared to the latter.

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

    NASA Astrophysics Data System (ADS)

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

    2013-10-01

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

  7. Photocatalytic degradation of methyl orange dye in water solutions in the presence of MWCNT/TiO{sub 2} composites

    SciTech Connect

    Da Dalt, S.; Alves, A.K.; Bergmann, C.P.

    2013-05-15

    Highlights: ? MWCNTs/TiO{sub 2} composites were obtained to degrade organic dyes in water. ? MWCNT/TiO{sub 2} composites were analyzed by photocatalysis and structural characterization. ? The photocatalytic shows efficient method for the degradation of dyes from aqueous effluents. - Abstract: The textile and dyestuff industries are the primary sources of the release of synthetic dyes into the environment and usually there are major pollutants in dye wastewaters. Because of their toxicity and slow degradation, these dyes are categorized as environmentally hazardous materials. In this context, carbon nanotubes/TiO{sub 2} (CNTs/TiO{sub 2}) composites were prepared using multi-walled CNTs (MWCNTs), titanium (IV) propoxide and commercial TiO{sub 2} (P25{sup ®}) as titanium oxide sources, to degrade the methyl orange dye in solution through photocatalyst activity using UV irradiation. The composites were prepared by solution processing followed by thermal treatment at 400, 500 and 600 °C. The heterojunction between nanotubes and TiO{sub 2} was confirmed by XRD, specific surface area. The coating morphology was observed with SEM and TEM.

  8. Selective removal of toxic anionic dyes using a novel nanocomposite derived from cationically modified guar gum and silica nanoparticles.

    PubMed

    Patra, Abhay Shankar; Ghorai, Soumitra; Ghosh, Shankhamala; Mandal, Barun; Pal, Sagar

    2016-01-15

    A novel nanocomposite derived from cationically modified guar gum and in-situ incorporated SiO2 NP (cat-GG/SiO2) has been developed. The cat-GG has been synthesised by grafting poly(2-(diethylamino)ethyl methacrylate) on GG backbone. Various analyses endorse the suitability of cat-GG as well-organized template for the development of homogeneous SiO2 NPs. Dye adsorption studies predict that cat-GG/SiO2 efficiently and selectively adsorb anionic dyes (reactive blue-RB and Congo red-CR) from mixture of dye solutions. This is because of high surface area, multifunctional chelating H-bonding interactions and electrostatic interactions of cationic adsorbent with anionic dyes. Dyes adsorbed on the composite surface are desorbed reversibly using pH 10 stripping solution. Besides, cat-GG/SiO2 has been recycled efficiently with no prominent loss of dye uptake capacity, even after 4 adsorption-desorption cycles. PMID:26348145

  9. Preferred Molecular Orientation of Coumarin 343 on TiO2 Surfaces: Application to Dye-Sensitized Solar Cells.

    PubMed

    McCree-Grey, Jonathan; Cole, Jacqueline M; Evans, Peter J

    2015-08-01

    The dye···TiO2 interfacial structure in working electrodes of dye-sensitized solar cells (DSCs) is known to influence its photovoltaic device performance. Despite this, direct and quantitative reports of such structure remain sparse. This case study presents the application of X-ray reflectometry to determine the preferred structural orientation and molecular packing of the organic dye, Coumarin 343, adsorbed onto amorphous TiO2. Results show that the dye molecules are, on average, tilted by 61.1° relative to the TiO2 surface, and are separated from each other by 8.2 Å. These findings emulate the molecular packing arrangement of a monolayer of Coumarin 343 within its crystal structure. This suggests that the dye adsorbs onto TiO2 in one of its lowest energy configurations; that is, dye···TiO2 self-assembly is driven more by thermodynamic rather than kinetic means. Complementary DSC device tests illustrate that this interfacial structure compromises photovoltaic performance, unless a suitably sized coadsorbant is interdispersed between the Coumarin 343 chromophores on the TiO2 surface. PMID:26159229

  10. Charge separation in solid-state dye-sensitized heterojunction solar cells

    SciTech Connect

    Bach, U.; Tachibana, Yasuhiro; Moser, J.E.; Haque, S.A.; Durrant, J.R.; Graetzel, M.; Klug, D.R.

    1999-08-18

    Dye-sensitized nanocrystalline solar cells are presently under intensive investigation, as they offer an attractive alternative to conventional p--n junction devices. Solid-state versions have been described where the electrolyte present in the pores of the malodorous oxide film is replaced by a large band gap p-type semiconductor. In this way, a solid-state heterojunction of very large contact area is formed. Light is absorbed by the dye that is located at the interface. Upon excitation, the dye injects electrons into the conduction band of the oxide and is regenerated by hole injection into the p-type conductor. High incident photon-to-electric current conversion efficiencies have been achieved recently with a cell consisting of a dye-derivatized mesoporous TiO{sub 2} film contacted by a new organic hole conductor. The great advantage of such systems with regard to conventional p--n junctions is that only majority carriers are involved in the photoelectric conversion process. Moreover, these are generated by the dye precisely at the site of the junction where the electric field is maximal, enhancing charge separation. Photoelectric conversion by conventional solar cells involves minority carriers whose lifetime is restricted due to recombination. As they are generated throughout the semiconductor and away from the junction, expensive high-purity materials are required in order to maintain the minority carrier diffusion length at a level where current losses are avoided. While the dynamics of photoinduced redo processes in photoelectrochemical systems have been studied in great detail, little is known about the electron-transfer dynamics in solid-state sensitized junctions. Here the authors report for the first time on the direct observation of photoinduced, interfacial charge separation across a dye-sensitized solid-state heterojunction by means of picosecond transient absorption laser spectroscopy.

  11. Laser velocimetry with fluorescent dye-doped polystyrene microspheres.

    PubMed

    Lowe, K Todd; Maisto, Pietro; Byun, Gwibo; Simpson, Roger L; Verkamp, Max; Danehy, Paul M; Tiemsin, Pacita I; Wohl, Christopher J

    2013-04-15

    Simultaneous Mie scattering and laser-induced fluorescence (LIF) signals are obtained from individual polystyrene latex microspheres dispersed in an air flow. Microspheres less than 1 ?m mean diameter were doped with two organic fluorescent dyes, Rhodamine B (RhB) and dichlorofluorescein (DCF), intended either to provide improved particle-based flow velocimetry in the vicinity of surfaces or to provide scalar flow information (e.g., marking one of two fluid streams). Both dyes exhibit measureable fluorescence signals that are on the order of 10(-3) to 10(-4) times weaker than the simultaneously measured Mie signals. It is determined that at the conditions measured, 95.5% of RhB LIF signals and 32.2% of DCF signals provide valid laser-Doppler velocimetry measurements compared with the Mie scattering validation rate with 6.5 W of 532 nm excitation, while RhB excited with 1.0 W incident laser power still exhibits 95.4% valid velocimetry signals from the LIF channel. The results suggest that the method is applicable to wind tunnel measurements near walls where laser flare can be a limiting factor and monodisperse particles are essential. PMID:23595429

  12. Voltage-Sensitive Dye Imaging of Neocortical Activity.

    PubMed

    Grinvald, Amiram; Omer, David B; Sharon, Dahlia; Vanzetta, Ivo; Hildesheim, Rina

    2016-01-01

    Neural computations underlying sensory perception, cognition, and motor control are performed by populations of neurons at different anatomical and temporal scales. Few techniques are currently available for exploring the dynamics of local and large range populations. Voltage-sensitive dye imaging (VSDI), based on organic voltage probes, reveals neural population activity in areas ranging from a few tens of micrometers to a couple of centimeters, or two areas up to ~10 cm apart. VSDI provides a submillisecond temporal resolution and a spatial resolution of ~50 µm. The dye signal emphasizes subthreshold synaptic potentials. VSDI has been applied in the mouse, rat, gerbil, ferret, tree shrew, cat, and monkey cortices to explore the lateral spread of retinotopic or somatotopic activation; the dynamic spatiotemporal pattern resulting from sensory activation, including the somatosensory, olfactory, auditory, and visual modalities; and motor preparation and the properties of spontaneously occurring population activity. In this introduction, we focus on VSDI in vivo and review results obtained mostly in the visual system in our laboratory. PMID:26729915

  13. Electrochemical treatment of textile dyes and dyehouse effluents.

    PubMed

    Chatzisymeon, Efthalia; Xekoukoulotakis, Nikolaos P; Coz, Alberto; Kalogerakis, Nicolas; Mantzavinos, Dionissios

    2006-09-21

    The electrochemical oxidation of textile effluents over a titanium-tantalum-platinum-iridium anode was investigated. Batch experiments were conducted in a flow-through electrolytic cell with internal recirculation at current intensities of 5, 10, 14 and 20A, NaCl concentrations of 0.5, 1, 2 and 4% and recirculation rates of 0.81 and 0.65 L/s using a highly colored, synthetic effluent containing 16 textile dyes at a total concentration of 361 mg/L and chemical oxygen demand (COD) of 281 mg/L. Moreover, an actual dyehouse effluent containing residual dyes as well as various inorganic and organic compounds with a COD of 404 mg/L was tested. In most cases, quantitative effluent decolorization was achieved after 10-15 min of treatment and this required low energy consumption; conversely, the extent of mineralization varied between 30 and 90% after 180 min depending on the operating conditions and the type of effluent. In general, treatment performance improved with increasing current intensity and salinity and decreasing solution pH. However, the use of electrolytes not containing chloride (e.g. FeSO4 or Na2SO4) suppressed degradation. Although the acute toxicity of the actual effluent to marine bacteria Vibrio fischeri was weak, it increased sharply following treatment, thus suggesting the formation of persistent toxic by-products. PMID:16713087

  14. Utilization of Naturally Occurring Dyes as Sensitizers in Dye Sensitized Solar Cells

    E-print Network

    Sawhney, Nipun

    2015-01-01

    Dye sensitized Solar cells (DSSCs) were fabricated with four naturally occurring anthocyanin dyes extracted from naturally found fruits/ juices (viz. Indian Jamun, Plum, Black Currant and Berries) as sensitizers. Extraction of anthocyanin was done using acidified ethanol. The highest power conversion efficiencies ({\\eta}) of 0.55% and 0.53% were achieved for the DSSCs fabricated using anthocyanin extracts of blackcurrant and mixed berry juice. Widespread availability of these fruits/juices, high concentration of anthocyanins in them and ease of extraction of anthocyanin dyes from these commonly available fruits render them novel and inexpensive candidates for solar cell fabrication.

  15. Synthesis, photophysical properties and application of dye doped water soluble silica-based nanoparticles to label bacteria E. coli O157:H7

    NASA Astrophysics Data System (ADS)

    Tan Pham, Minh; Van Nguyen, Thi; Thi, Thuy Duong Vu; Nghiem Thi, Ha Lien; Thuan Tong, Kim; Thuy Tran, Thanh; Chu, Viet Ha; Brochon, Jean-Claude; Nhung Tran, Hong

    2012-12-01

    Organically modified silicate (ORMOSIL) nanoparticles (NPs) doped with rhodamine 6G and rhodamine B (RB) dyes were synthesized by Stöber method from methyltriethoxysilane CH3Si(OCH3)3 precursor (MTEOS). The NPs are surface functionalized by cationic amino groups. The optical characterization of dye-doped ORMOSIL NPs was studied in comparison with that of free dye in solution. The synthesized NPs were used for labeling bacteria E. coli O157:H7. The number of bacteria have been counted using the fluorescent spectra and microscope images of labeled bacteria. The results show the ability of NPs to work as biomarkers.

  16. Decoloration of textile dyes by alginate-immobilized Trametes versicolor

    E-print Network

    Ramsay, Juliana

    Decoloration of textile dyes by alginate-immobilized Trametes versicolor J.A. Ramsay *, W.H.W. Mok rights reserved. Keywords: Alginate; Decoloration; Textile dye; T. versicolor 1. Introduction White rot cinna- barinus (Schliephake and Lonergan, 1993) have been shown to decolorize textile dyes or colored

  17. Surface plasmon enhanced emission from dye doped polymer layers

    E-print Network

    Okamoto, Koichi

    Surface plasmon enhanced emission from dye doped polymer layers Terrell D. Neal,a) Koichi Okamoto the plasmon frequency of a thin unpatterned silver film to the emission of a dye doped polymer deposited onto layer, we estimate that the plasmon frequency can be tuned to match dye doped polymer emission

  18. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Substituted azo metal complex dye. 721.4594 Section 721...Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance...identified generically as a substituted azo metal complex dye (PMN P-94-499) is...

  19. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Substituted azo metal complex dye. 721.4594 Section 721...Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance...identified generically as a substituted azo metal complex dye (PMN P-94-499) is...

  20. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dye and chemical solution stains. 864.1850 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures...

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

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dye and chemical solution stains. 864.1850 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures...

  2. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dye and chemical solution stains. 864.1850 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures...

  3. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dye and chemical solution stains. 864.1850 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures...

  4. 21 CFR 864.1850 - Dye and chemical solution stains.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dye and chemical solution stains. 864.1850 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and chemical solution stains for medical purposes are mixtures...

  5. Dye lasers. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Cavagnaro, D. M.

    1980-08-01

    This bibliography covers studies on dye laser theory, design, components, optical systems, and frequency range. Abstracts on lasing dyes, pumping, tuning, excitation, molecular structure, and modulation are included. Studies on dye laser use in spectroscopy are covered. This updated bibliography contains 217 citations, none of which are new entries to the previous edition.

  6. Highly efficient degradation of dye pollutants by Ce-doped MoO? catalyst at room temperature.

    PubMed

    Jin, Yujian; Li, Na; Liu, Haiqiu; Hua, Xia; Zhang, Qiuying; Chen, Mindong; Teng, Fei

    2014-09-14

    In order to efficiently degrade organic pollutants via an easily operated method, Ce-doped MoO3 (Ce(x)/MoO3) samples are synthesized by a simple impregnation method. The samples are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), nitrogen sorption isotherms and UV-vis diffused reflectance spectra (UV-DRS), total organic carbon (TOC), infrared spectroscopy (IR) and mass spectrometry (MS) analyses. Furthermore, we have mainly investigated the degradation of different dye pollutants by the Ce(x)/MoO3 samples, including cationic methylene blue (MB), anionic methyl orange (MO), neutral phenol, and a MB-MO mixture dye. For the single-component MB and MO dyes, the highest degradation efficiencies are achieved by Ce(5)/MoO3 and Ce(10)/MoO3 samples. For the MB-MO mixture dyes, the highest degradation efficiency for MB is achieved by a Ce(10)/MoO3 sample. It is surprising that the degradation efficiency of MB in the MB-MO mixture dye solution is higher than that in the single-component MB dye solution, which has been mainly ascribed to the promoting effect of MO. Moreover, a plausible degradation mechanism of the dyes has been proposed and discussed. It should be noted that the degradation reaction is carried out at room temperature and normal atmospheric pressure, and without light irradiation. As a result, this degradation reaction is obviously different from the conventional thermally activated heterogeneous catalysis (or photocatalysis), in which thermal energy (or light irradiation) is indispensable; also different from a sorption technology, in which the pollutants cannot be degraded, but only transformed from one phase to another one. Thus, the reported degradation reaction is a quite promising environmental cleaning technology, which could be widely practically applied. PMID:25019412

  7. Orientational Dynamics and Dye-DNA Interactions in a Dye-Labeled DNA Aptamer

    E-print Network

    Wilson, George S.; Unruh, Jay R.; Gokulrangan, Giridharan; Lushington, Gerald H.; Johnson, Carey K.

    2005-05-01

    We report the picosecond and nanosecond timescale rotational dynamics of a dye-labeled DNA oligonucleotide or ‘‘aptamer’’ designed to bind specifically to immunoglobulin E. Rotational dynamics in combination with fluorescence ...

  8. Dye-sensitized solar cells with natural dyes extracted from plant seeds

    NASA Astrophysics Data System (ADS)

    El-Ghamri, Hatem S.; El-Agez, Taher M.; Taya, Sofyan A.; Abdel-Latif, Monzir S.; Batniji, Amal Y.

    2014-12-01

    The application of natural dyes extracted from plant seeds in the fabrication of dye-sensitized solar cells (DSSCs) has been explored. Ten dyes were extracted from different plant seeds and used as sensitizers for DSSCs. The dyes were characterized using UV-Vis spectrophotometry. DSSCs were prepared using TiO2 and ZnO nanostructured mesoporous films. The highest conversion efficiency of 0.875 % was obtained with an allium cepa (onion) extract-sensitized TiO2 solar cell. The process of TiO2-film sintering was studied and it was found that the sintering procedure significantly affects the response of the cell. The short circuit current of the DSSC was found to be considerably enhanced when the TiO2 semiconducting layer was sintered gradually.

  9. Biodegradation and detoxification of textile azo dyes by bacterial consortium under sequential microaerophilic/aerobic processes

    PubMed Central

    Lade, Harshad; Kadam, Avinash; Paul, Diby; Govindwar, Sanjay

    2015-01-01

    Release of textile azo dyes to the environment is an issue of health concern while the use of microorganisms has proved to be the best option for remediation. Thus, in the present study, a bacterial consortium consisting of Providencia rettgeri strain HSL1 and Pseudomonas sp. SUK1 has been investigated for degradation and detoxification of structurally different azo dyes. The consortium showed 98-99 % decolorization of all the selected azo dyes viz. Reactive Black 5 (RB 5), Reactive Orange 16 (RO 16), Disperse Red 78 (DR 78) and Direct Red 81 (DR 81) within 12 to 30 h at 100 mg L-1 concentration at 30 ± 0.2 °C under microaerophilic, sequential aerobic/microaerophilic and microaerophilic/aerobic processes. However, decolorization under microaerophilic conditions viz. RB 5 (0.26 mM), RO 16 (0.18 mM), DR 78 (0.20 mM) and DR 81 (0.23 mM) and sequential aerobic/microaerophilic processes viz. RB 5 (0.08 mM), RO 16 (0.06 mM), DR 78 (0.07 mM) and DR 81 (0.09 mM) resulted into the formation of aromatic amines. In distinction, sequential microaerophilic/ aerobic process doesn’t show the formation of amines. Additionally, 62-72 % reduction in total organic carbon content was observed in all the dyes decolorized broths under sequential microaerophilic/aerobic processes suggesting the efficacy of method in mineralization of dyes. Notable induction within the levels of azoreductase and NADH-DCIP reductase (97 and 229 % for RB 5, 55 and 160 % for RO 16, 63 and 196 % for DR 78, 108 and 258 % for DR 81) observed under sequential microaerophilic/aerobic processes suggested their critical involvements in the initial breakdown of azo bonds, whereas, a slight increase in the levels of laccase and veratryl alcohol oxidase confirmed subsequent oxidation of formed amines. Also, the acute toxicity assay with Daphnia magna revealed the nontoxic nature of the dye-degraded metabolites under sequential microaerophilic/aerobic processes. As biodegradation under sequential microaerophilic/aerobic process completely detoxified all the selected textile azo dyes, further efforts should be made to implement such methods for large scale dye wastewater treatment technologies. PMID:26417357

  10. Biodegradation and detoxification of textile azo dyes by bacterial consortium under sequential microaerophilic/aerobic processes.

    PubMed

    Lade, Harshad; Kadam, Avinash; Paul, Diby; Govindwar, Sanjay

    2015-01-01

    Release of textile azo dyes to the environment is an issue of health concern while the use of microorganisms has proved to be the best option for remediation. Thus, in the present study, a bacterial consortium consisting of Providencia rettgeri strain HSL1 and Pseudomonas sp. SUK1 has been investigated for degradation and detoxification of structurally different azo dyes. The consortium showed 98-99 % decolorization of all the selected azo dyes viz. Reactive Black 5 (RB 5), Reactive Orange 16 (RO 16), Disperse Red 78 (DR 78) and Direct Red 81 (DR 81) within 12 to 30 h at 100 mg L(-1) concentration at 30 ± 0.2 °C under microaerophilic, sequential aerobic/microaerophilic and microaerophilic/aerobic processes. However, decolorization under microaerophilic conditions viz. RB 5 (0.26 mM), RO 16 (0.18 mM), DR 78 (0.20 mM) and DR 81 (0.23 mM) and sequential aerobic/microaerophilic processes viz. RB 5 (0.08 mM), RO 16 (0.06 mM), DR 78 (0.07 mM) and DR 81 (0.09 mM) resulted into the formation of aromatic amines. In distinction, sequential microaerophilic/ aerobic process doesn't show the formation of amines. Additionally, 62-72 % reduction in total organic carbon content was observed in all the dyes decolorized broths under sequential microaerophilic/aerobic processes suggesting the efficacy of method in mineralization of dyes. Notable induction within the levels of azoreductase and NADH-DCIP reductase (97 and 229 % for RB 5, 55 and 160 % for RO 16, 63 and 196 % for DR 78, 108 and 258 % for DR 81) observed under sequential microaerophilic/aerobic processes suggested their critical involvements in the initial breakdown of azo bonds, whereas, a slight increase in the levels of laccase and veratryl alcohol oxidase confirmed subsequent oxidation of formed amines. Also, the acute toxicity assay with Daphnia magna revealed the nontoxic nature of the dye-degraded metabolites under sequential microaerophilic/aerobic processes. As biodegradation under sequential microaerophilic/aerobic process completely detoxified all the selected textile azo dyes, further efforts should be made to implement such methods for large scale dye wastewater treatment technologies. PMID:26417357

  11. Analysing flow patterns in degraded peat soils using TiO2 dye

    NASA Astrophysics Data System (ADS)

    Liu, Haojie; Lennartz, Bernd

    2014-05-01

    Dye tracing is a valuable method for studying the flow patterns in soils. However, limited information is available on water flow and solute transport pathways in dark colored peat soils because the frequently used Brilliant Blue FCF dye does not visibly stain the soil. In this study, we were aiming at testing the suitability of Titanium dioxide (TiO2) as a dye tracer for dark peat soils. The objectives were to quantify the physical properties of different degraded peat soils and visualize the flow patterns. Soil samples were collected from two low-lying fen sites, where the top soil was highly degraded, while lower horizons were less decomposed. Dye tracer experiments were conducted at both sites by applying a TiO2 suspension (10 g/l) with a pulse of 40 mm. Soil profiles were prepared for photo documentation the following day. It was found that the physical and hydraulic properties of peat were significantly influenced by the degree of peat decomposition and degradation. Higher decomposed and degraded peat soils had a higher bulk density, lower organic matter content and lower porosity. Moreover, higher decomposition and degradation resulted in a lower saturated hydraulic conductivity as long as investigated samples originated from the same site. In addition, degraded peat soils showed less anisotropy than un-degraded peat. It turned out that TiO2 is a suitable dye tracer to visualize the flow paths in peat soils. Although dye patterns differed within the same plot and between different plots, most of the flow patterns indicated a preferential flow situation. The distribution of TiO2 in the soil profile, as analyzed from 5 by 5 cm grid cells, compared to the distribution of bromide, which was applied along with the dye confirming the suitability of the dye tracer. Un-decomposed plant structures, such as wood branches and leaves, were identified as the major preferential flow path in un-degraded peat. For degraded peat, bio-pores, such as root and earthworm channels operated as the major transport domain.

  12. Using dye markers to reduce pesticide use

    E-print Network

    wavelengths or colours in white light. The colour seen by a human eye is determined by the wavelengths Commission initiated a series of small-scale experiments with the aim of identifying potentially safe, cheap, alternative marker dyes. The experiments investigated a wide range of commercially available products, textile

  13. Mutagenicity testing of some commonly used dyes.

    PubMed

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

    1981-10-01

    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

  14. Fiber Chemistry Effects on Dye Uptake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dyeing efficiency of cotton knits was investigated as a function both of metal contents native to the cotton fiber as well as the presence of sugar-protein reaction products which contribute to +b. Results indicate that aged cotton fiber exhibits both a higher +b value and a tendency to incorpor...

  15. Fluorescent indicator dyes for calcium ions

    NASA Technical Reports Server (NTRS)

    Tsien, Roger Y. (Inventor); Grynkiewicz, Grzegorz (Inventor)

    1986-01-01

    The present invention discloses a new class of highly fluorescent indicator dyes that are specific for calcium ions. The new fluorescent indicator dyes combine a stilbene-type fluorophore with a tetracarboxylate parent Ca.sup.2+ chelating compound having the octacoordinate pattern of liganding groups characteristic of EGTA and BAPTA. Preferred forms contain extra heterocyclic bridges to reinforce the ethylenic bond of the stilbene and to reduce hydrophobicity. Compared to their widely used predecessor, quin2, the new dyes offer up to thirty-fold brighter fluorescence, major changes in wavelength (not just intensity) upon Ca.sup.2+ binding, slightly lower affinities for Ca.sup.2+, slightly longer wavelengths of excitation, and considerably improved selectivity for Ca.sup.2+ over other divalent cations. These properties, particularly the wavelength sensitivity to Ca.sup.2+, make the dyes useful indicators for many intracellular applications, especially in single cells, adherent cell layers, or bulk tissues. The present invention also discloses an improved method for synthesizing alpha-acyloxyalkyl bromides wherein the bromides so synthesized are free of contaminating bis(1-bromoalkyl)ether. The improved method is exemplified herein in the synthesis of acetoxymethyl bromide, a compound useful in preparing the acetoxymethyl esters disclosed herein as novel Ca.sup.2+ specific fluorescent indicators.

  16. Photonic effects on the fluorescence lifetimes of dyes in thin PVA layers

    NASA Astrophysics Data System (ADS)

    Prangsma, Jord C.; Molenaar, Robert; Subramaniam, Vinod; Blum, Christian

    2015-08-01

    In this paper we investigate the expected change in fluorescent decay rate when a fluorophore in aqueous solution is moved to a thin spin-coated layer of poly(vinyl alcohol). We take into account the local field effect due to the change in the refractive index of the medium around the fluorophore and the photonic effect due to the layers. The obtained results are compared with experimental results for the organic dye Atto565 and the fluorescent protein mCherry. We find that the effects for the organic dye can be well described with the model, for the fluorescent protein (FP) the model is less accurate. We discuss the possible explanations for this.

  17. Dye-sensitized solar cells with improved performance using cone-calix[4]arene based dyes.

    PubMed

    Tan, Li-Lin; Liu, Jun-Min; Li, Shao-Yong; Xiao, Li-Min; Kuang, Dai-Bin; Su, Cheng-Yong

    2015-01-01

    Three cone-calix[4]arene-based sensitizers (Calix-1-Calix-3) with multiple donor-?-acceptor (D-?-A) moieties are designed, synthesized, and applied in dye-sensitized solar cells (DSSCs). Their photophysical and electrochemical properties are characterized by measuring UV/Vis absorption and emission spectra, cyclic voltammetry, and density functional theory (DFT) calculations. Calix-3 has excellent thermo- and photostability, as illustrated by thermogravimetric analysis (TGA) and dye-aging tests, respectively. Importantly, a DSSC using the Calix-3 dye displays a conversion efficiency of 5.48?% in under standard AM?1.5 Global solar illumination conditions, much better than corresponding DSSCs that use the rod-shaped dye M-3 with a single D-?-A chain (3.56?%). The dyes offer advantages in terms of higher molar extinction coefficients, longer electron lifetimes, better stability, and stronger binding ability to TiO2 film. This is the first example of calixarene-based sensitizers for efficient dye-sensitized solar cells. PMID:25183482

  18. Random laser action in dye doped nanoporous polymeric film

    NASA Astrophysics Data System (ADS)

    Lü, Jiantao; Fan, Ting; Chen, Guojie

    2015-12-01

    We report on the demonstration of random lasing action in dye doped nanoporous polymer films fabricated by spin-coating method. Through the photoluminescence experiment we found that the multimode lasing occurs due to the multiple light scattering processes, while the holes distributed randomly in the samples play the role of scattering centers. Above the lasing threshold, some discrete peaks with a linewidth less than 0.4 nm emerge upon the broad spontaneous band and the system shows the linear input-output characteristics. The lasing threshold and slope efficiency show a dependence on the diameter of the holes. Our work enriches the field of organic random lasers and brings out a new type of active disordered medium.

  19. Preparation and characterization of 'green' hybrid clay-dye nanopigments

    NASA Astrophysics Data System (ADS)

    Kaya, Mehmet; Onganer, Yavuz; Tabak, Ahmet

    2015-03-01

    We obtained a low cost and abundant nanopigment material composed of Rhodamine B (Rh-B) organic dye compound and Unye bentonite (UB) clay from Turkey. The characterization of the nanopigment was investigated using scanning electron microscopy (SEM), particle size distribution, powder X-ray diffraction (PXRD), Fourier transformed infra-red spectroscopy (FT-IR) and thermal analysis techniques. According to the result of texture analyses, we showed that the particle size distribution (d: 0.5-mean distribution) of Rh-B/UB nanopigment material was around 100 nm diameter. It was also demonstrated that the samples had a particle size around nm diameter in SEM images. As seen in the PXRD and thermal analysis, there is a difference in basal spacing by 1.46° (2?) and a higher mass loss by 7.80% in the temperature range 200-500 °C compared to the raw bentonite.

  20. Organic Dyes, Conjugation, and the Chemistry of Vision

    E-print Network

    Amar, François G.

    white light is dispersed through a prism UV IR remember ROY G BIV #12;Two()2. Bond order = (4-0)/2 = 2 light absorbed C=C Excited state configuration of the C-C bond: ()2()1( )1. Bond order = (3-1)/2 = 1 E=h C-C #12;Light The spectrum of white light is obtained when

  1. Uniform silica nanoparticles encapsulating two-photon absorbing fluorescent dye

    SciTech Connect

    Wu Weibing; Liu Chang; Wang Mingliang; Huang Wei; Zhou Shengrui; Jiang Wei; Sun Yueming; Cui Yiping; Xu Chunxinag

    2009-04-15

    We have prepared uniform silica nanoparticles (NPs) doped with a two-photon absorbing zwitterionic hemicyanine dye by reverse microemulsion method. Obvious solvatochromism on the absorption spectra of dye-doped NPs indicates that solvents can partly penetrate into the silica matrix and then affect the ground and excited state of dye molecules. For dye-doped NP suspensions, both one-photon and two-photon excited fluorescence are much stronger and recorded at shorter wavelength compared to those of free dye solutions with comparative overall dye concentration. This behavior is possibly attributed to the restricted twisted intramolecular charge transfer (TICT), which reduces fluorescence quenching when dye molecules are trapped in the silica matrix. Images from two-photon laser scanning fluorescence microscopy demonstrate that the dye-doped silica NPs can be actively uptaken by Hela cells with low cytotoxicity. - Graphical abstract: Water-soluble silica NPs doped with a two-photon absorbing zwitterionic hemicyanine dye were prepared. They were found of enhanced one-photon and two-photon excited fluorescence compared to free dye solutions. Images from two-photon laser scanning fluorescence microscopy demonstrate that the dye-doped silica NPs can be actively uptaken by Hela cells.

  2. The Use of Vital Dyes during Vitreoretinal Surgery - Chromovitrectomy.

    PubMed

    Farah, Michel Eid; Maia, Maurício; Penha, Fernando M; Rodrigues, Eduardo Büchele

    2016-01-01

    The aim of this article is to present the current data with regard to the application of vital dyes during vitreoretinal surgery, 'chromovitrectomy', as well as to overview the current literature regarding the properties of dyes, techniques of application, indications and complications in chromovitrectomy. It is well known that indocyanine green is toxic to the retina and consequently not the ideal dye for chromovitrectomy. Different vital dyes has been tested for chromovitrectomy including trypan blue, patent blue, triamcinolone acetonide, infracyanine green, sodium fluorescein and brilliant blue. Brilliant blue seems to be the ideal dye for internal limiting membrane due to its afinity, lower toxic profile and to reduce the appearance of apoptosis. Besides the dye itself, the injection technique is crucial to avoid additional toxicity, slow injection, far from the retina and protection of the macular hole are some tips. More recently the use of dyes has been applied to stain perfluorcarbon liquids that may enhance its visualization during vitrectomy. PMID:26502062

  3. Novel method for evaluation of natural dyes in DSSC

    SciTech Connect

    Lakshmi, M.; Kavitha, S.; Paul, Mercyleena

    2014-10-15

    Dye sensitized Solar Cell (DSSC) is presently centered on Ruthenium based dyes. Recent research is diverted to explore the potential of natural dyes in replacing the conventional dyes. In this work we have chosen few natural dyes, which when coated on TiO{sub 2} leads to increase in absorption capacity of TiO{sub 2}. Co-relation of absorption and electrochemical properties of natural dyes gives a scientific insight of the probable performance of a dye, even without fabricating a cell. We have tried to compare this predictions based on HOMO-LUMO energy levels with the real cell performance. Measurements of cell parameters suggest that there is scope for further research in this area.

  4. Synthesis, physiochemical and optical properties of chitosan based dye containing naphthalimide group.

    PubMed

    Kumar, Santosh; Koh, Joonseok

    2013-04-15

    A new biopolymer dye containing naphthalimide moiety was synthesized by reaction of N-naphthaloyl chitosan with 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-piperazino-3-quinolinecarboxylic acid. N-naphthaloyl chitosan was synthesized by reaction of chitosan with 4-bromo-1,8-naphthalic anhydride in aqueous media by greener approach. The degree of substitution of chitosan biopolymer dye is 0.55 with a yield of 70%. The synthesized materials were characterized by using UV-vis, (1)H NMR, FTIR, and FT-Raman spectroscopy. Some physical properties and surface morphology were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Optical properties of chitosan biopolymer dye were evaluated by photoluminescence (PL) spectroscopy that showed red shift (?(em)) peak at 442 nm and 551 nm at excitation wavelength 325 nm in comparison to chitosan. The solubility of chitosan biopolymer dye increased in most of the organic solvents. These results may provide new perspectives in biomedical applications as an optical and sensitive biosensor material. PMID:23544532

  5. Pulsed dye laser application in ablation of vascular ectasias of the larynx: a preliminary animal study

    NASA Astrophysics Data System (ADS)

    Woo, Peak; Wang, Zhi; Perrault, Donald F., Jr.; McMillan, Kathleen; Pankratov, Michail M.

    1995-05-01

    Vascular ectasias (dilatation) and vascular lesions of the larynx are difficult to treat with exciting modalities. Varix (enlarged vessel) of the vocal folds, vocal fold hemorrhage, vascular polyp, hemangioma, intubation or contact granuloma are common problems which disturb voice. Current applications of CO2 laser and cautery often damage the delicate vocal fold cover. The 585 nm dermatologic pulsed dye laser may be an ideal substitute. Two adult canines were examined under anesthesia via microlaryngoscopy technique. Pulsed dye laser (SPTL-1a, Candela Laser Corp., Wayland, MA) energy was delivered via the micromanipulator with the 3.1-mm spot size in single pulses of 6, 8, and 10 Joules/cm2 and applied to the vessels of the vocal folds, epiglottis, and arytenoid cartilage. Endoscopic examination was carried out immediately after the treatment and at 4 weeks postoperatively. The animals were sacrificed at 3 weeks, larynges excised, and whole organ laryngeal section were prepared for histology. Pulsed dye laser thrombosed vessels of the vocal fold using 6 or 8 Joules/cm2. Vascular break and leakage occurred at 10 Joules/cm2. Follow up examination showed excellent vessel obliteration or thrombosis without scarring or injury to the overlying tissues. Histologic examination shows vascular thrombosis without inflammation and fibrosis in the vocal fold cover. Pulsed dye laser may have promise in treatment of vascular lesions of the larynx and upper airway.

  6. Magneto-fluorescent hybrid of dye and SPION with ordered and radially distributed porous structures

    NASA Astrophysics Data System (ADS)

    Gogoi, Madhulekha; Deb, Pritam

    2014-04-01

    We have reported the development of a silica based magneto-fluorescent hybrid of a newly synthesized dye and superparamagnetic iron oxide nanoparticles with ordered and radially distributed porous structure. The dye is synthesized by a novel yet simple synthetic approach based on Michael addition between dimer of glutaraldehyde and oleylamine molecule. The surfactant used for phase transformation of the dye from organic to aqueous phase, also acts as a structure directing agent for the porous structure evolution of the hybrid with radial distribution. The evolution of the radially distributed pores in the hybrids can be attributed to the formation of rod-like micelles containing nanoparticles, for concentration of micelles greater than critical micelle concentration. A novel water extraction method is applied to remove the surfactants resulting in the characteristic porous structure of the hybrid. Adsorption isotherm analysis confirms the porous nature of the hybrids with pore diameter ?2.4 nm. A distinct modification in optical and magnetic property is observed due to interaction of the dye and SPION within the silica matrix. The integration of multiple structural components in the so developed hybrid nanosystem results into a potential agent for multifunctional biomedical application.

  7. Wavelength dependence of reversible photodegradation of disperse orange 11 dye-doped PMMA thin films

    E-print Network

    Anderson, Benjamin R; Kuzyk, Mark G

    2015-01-01

    Using transmittance imaging microscopy we measure the wavelength dependence of reversible photodegradation in disperse orange 11 (DO11) dye-doped (poly)methyl-methacrylate (PMMA). The reversible and irreversible inverse quantum efficiencies (IQEs) are found to be constant over the spectral region investigated, with the average reversible IQE being $\\overline{B}_\\alpha= 8.70 (\\pm 0.38)\\times 10^5$ and the average irreversible IQE being $\\overline{B}_\\epsilon= 1.396 (\\pm 0.031)\\times 10^8$. The large difference between the IQEs is hypothesized to be due to the reversible decay channel being a direct decay mechanism of the dye, while the irreversible decay channel is an indirect mechanism, with the dye first absorbing light, then heating the surrounding environment causing polymer chain scission and cross linking. Additionally, the DO11/PMMA's irreversible IQE is found to be among the largest of those reported for organic dyes, implying that the system is highly photostable. We also find that the recovery rate i...

  8. Diketopyrrolopyrrole: brilliant red pigment dye-based fluorescent probes and their applications.

    PubMed

    Kaur, Matinder; Choi, Dong Hoon

    2015-01-01

    The development of fluorescent probes for the detection of biologically relevant species is a burgeoning topic in the field of supramolecular chemistry. A number of available dyes such as rhodamine, coumarin, fluorescein, and cyanine have been employed in the design and synthesis of new fluorescent probes. However, diketopyrrolopyrrole (DPP) and its derivatives have a distinguished role in supramolecular chemistry for the design of fluorescent dyes. DPP dyes offer distinctive advantages relative to other organic dyes, including high fluorescence quantum yields and good light and thermal stability. Significant advancements have been made in the development of new fluorescent probes based on DPP in recent years as a result of tireless research efforts by the chemistry scientific community. In this tutorial review, we highlight the recent progress in the development of DPP-based fluorescent probes for the period spanning 2009 to the present time and the applications of these probes to recognition of biologically relevant species including anions, cations, reactive oxygen species, thiols, gases and other miscellaneous applications. This review is targeted toward providing the readers with deeper understanding for the future design of DPP-based fluorogenic probes for chemical and biological applications. PMID:25186723

  9. Scattering particles increase absorbance of dyes - a model study with relevance for sunscreens.

    PubMed

    Herzog, Bernd; Sengün, Fazilet

    2015-10-28

    Sunscreens used for the protection of human skin against the harmful effects of solar radiation contain UV absorbers as key ingredients, which are either dissolved in one of the phases of the preparation or, when insoluble, suspended as particles. Although the UV protective effect of particulate UV filters, inorganic and organic, is mainly due to absorption, they scatter UV and visible light. The scattering can have an additional attenuating effect on the incoming radiation by increasing the pathlength of the photons, especially when soluble filters are also present. This is investigated with model systems of dyes and absorbing and non-absorbing particles. The presence of particles causes an increase of the dye absorbance without changing dye concentration or cuvette thickness. It is possible to relate this amplification of dye absorbance to the turbidity of the system. Plots are constructed which allow for a given particle type the representation of all data on one single curve, though measured at different turbidity and cuvette thickness. With that, extrapolations to practical applications of sunscreens are possible. PMID:26356574

  10. Conversion of the luminescence of laser dyes in opal matrices to stimulated emission

    SciTech Connect

    Alimov, O K; Basiev, T T; Orlovskii, Yu V; Osiko, V V; Samoilovich, M I

    2008-07-31

    The luminescence and laser characteristics of a synthetic opal matrix filled with organic dyes are studied upon excitation by nanosecond laser pulses. The appearance of stimulated emission in a partially ordered scattering medium is investigated. It is shown that if the luminescence spectrum of a dye (oxazine-17) is located far outside the photonic bandgap of the opal matrix, stimulated emission along a preferential direction in the (111) plane is observed when pumping exceeds a threshold even without an external optical cavity. The stimulated emission spectrum is considerably narrower than the luminescence spectrum and consists of several narrow lines located within the dye luminescence band. If the luminescence spectrum of a dye (rhodamine 6G) overlaps with the photonic bandgap of the opal matrix, a different picture is observed. The loss of radiation in the matrix leads to the red shift of the luminescence spectrum, while the stimulated emission as in the case of oxazine-17 lies is observed within the luminescence band. (active media, lasers, and amplifiers)

  11. Electro-Fenton decolourisation of dyes in an airlift continuous reactor using iron alginate beads.

    PubMed

    Iglesias, O; Rosales, E; Pazos, M; Sanromán, M A

    2013-04-01

    In this study, electro-Fenton dye degradation was performed in an airlift continuous reactor configuration by harnessing the catalytic activity of Fe alginate gel beads. Electro-Fenton experiments were carried out in an airlift reactor with a working volume of 1.5 L, air flow of 1.5 L/min and 115 g of Fe alginate gel beads. An electric field was applied by two graphite bars connected to a direct current power supply with a constant potential drop. In this study, Lissamine Green B and Reactive Black 5 were selected as model dyes. Fe alginate gel beads can be used as an effective heterogeneous catalyst for the degradation of organic dyes in the electro-Fenton process, as they are more efficient than the conventional electrochemical techniques. At optimal working conditions (3 V and pH 2), the continuous process was performed. For both dyes, the degree of decolourisation increases when the residence time augments. Taking into account hydrodynamic and kinetic behaviour, a model to describe the reactor profile was obtained, and the standard deviation between experimental and theoretical data was lower than 6%. The results indicate the suitability of the electro-Fenton technique to oxidise polluted effluents in the presence of Fe alginate gel beads. Moreover, the operation is possible in a continuous airlift reactor, due to the entrapment of iron in the alginate matrix. PMID:22851224

  12. 9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Samples of products, water, dyes, chemicals, etc., to be taken for examination. 318.9 Section 318.9 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND...

  13. Effect of dye concentration on the optical properties of red-BS dye-doped PVA film

    NASA Astrophysics Data System (ADS)

    Hossein Esfahani, Zahra; Ghanipour, Mahshad; Dorranian, Davoud

    2014-07-01

    In this experimental study, the effect of dye concentration on the optical properties of red-BS dye-doped polyvinyl alcohol (PVA) thin films is investigated. Three thin film samples with different concentration of red-BS dye were prepared by spin-coating method on the glass substrate. Using transmission and reflection spectrum of films, their optical parameter such as refractive index, absorption coefficient, and dielectric function are extracted and the effect of dye impurity on theses parameters has been studied. The band gap energy of samples is calculated using Tauc method. Band gap energy of samples is decreased by increasing the concentration of dye impurity in PVA films.

  14. Multiple equilibria of phenothiazine dyes in aqueous cyclodextrin solutions

    SciTech Connect

    Lee, C.; Sung, Y.W.; Park, J.W.

    1999-02-04

    A wide variety of applications of the phenothiazine (PN) dyes have been reported, for example, as sensitizers in solar energy conversion. The dimerization and inclusion complexation equilibria of six phenothiazine dyes with cyclodextrins ({alpha}-, {beta}-, and {gamma}-CDs) in aqueous media have been studied using absorption and fluorescence spectroscopy. The PN dyes used in this study are thionine (TH), azure A (AZA), methylene blue (MB), toluidine blue (TB), new methylene blue (NMB), and 1,9-dimethylmethylene blue (DMMB). The dimerization constants (K{sub D}) of the dyes having two methyl substituents at the phenothiazine ring (NMB and DMMB) are much greater than those of other dyes having unsubstituted rings, and the presence of methyl groups on the amine groups affects little the K{sub D} values. The positions of the monomer/dimer equilibria do not change with the presence of {alpha}-CD, while the addition of {beta}-CD suppresses and {gamma}-CD enhances the dimerization of the dyes except DMMB. The equilibrium constants for the inclusion complexation of the dye monomers and dimers with CDs are determined from the analysis of the dependence of the absorption spectra of the dye solutions on the concentrations of the CDs using a multiple-equilibrium scheme. The results indicated that, except DMMB, which has methyl groups at the 1-position of the fused phenothiazine ring, the dye monomers fit better to {beta}-CD and the dimers fit snugly to {gamma}-CD. Fluorescence spectroscopic studies indicate that the dye dimers are not fluorescent and inclusion of the monomer in {beta}-CD results in a 3--5 times enhancement of fluorescence intensity. The determined equilibrium constants of the multiple-equilibrium scheme of the dyes in CD media and fluorescent properties of the dyes can be used to control the dye aggregation and the photophysical and photochemical properties of the phenothiazine dyes for various applications.

  15. Charge and Energy Transfer in the Metal-free Indoline Dyes for Dye-sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Diao, Li-ying; Gu, Wen-xiang; Chen, Yue-hui; Ma, Feng-cai

    2006-06-01

    Metal-free indoline dyes for dye-sensitized solar cells were studied by employing quantum chemistry methods. Comparative study of the properties of both ground and excited states of metal-free indoline dyes for dye- sensitized solar cells revealed: (i) as the number of rhodanine rings increases, the energy difference between HOMO and LUMO decreases and there is a red shift in the absorption spectrum with the binding energy increased, and the transition dipole moment decreased; (ii) Based on an analysis of charge differential density, we observed that the charge and energy are transfered from the phenylethenyl to the indoline and rhodanine rings; (iii) The electron-hole coherences are mainly on the indoline and rhodanine rings, and the exciton sizes are 30 and 40 atoms for indoline dyes with one and two rhodanline rings, respectively. These results serve as a good example of computer-aided design in metal-free indoline dyes for dye-sensitized solar cells.

  16. Heptamethine carbocyanine dye-mediated near-infrared imaging of canine and human cancers through the HIF-1?/OATPs signaling axis

    PubMed Central

    Shi, Changhong; Wu, Jason Boyang; Chu, Gina C-Y.; Li, Qinlong; Wang, Ruoxiang; Zhang, Caiqin; Zhang, Yi; Kim, Hyung L.; Wang, Jing; Zhau, Haiyen E.; Pan, Dongfeng; Chung, Leland W.K.

    2014-01-01

    Near-infrared (NIR) fluorescence imaging agents are promising tools for noninvasive cancer imaging. This study explored the specific uptake and retention of a NIR heptamethine carbocyanine MHI-148 dye by canine cancer cells and tissues and human prostate cancer (PCa) specimens and also the dye uptake mechanisms. The accumulation of MHI-148 was detected specifically in canine cancer cells and tissues and freshly harvested human PCa tissues xenografted in mice by NIR fluorescence microscopy and whole-body NIR optical imaging. Specific dye uptake in canine spontaneous tumors was further confirmed by PET imaging. Higher hypoxia-inducible factor-1? (HIF-1?) and organic anion-transporting polypeptide (OATP) protein and mRNA expression was demonstrated by multiplex quantum dots labeling and qPCR in tumors over that of normal tissues. Treating cancer cells with HIF-1? stabilizers activated HIF-1? downstream target genes, induced OATP superfamily gene expression and enhanced cellular uptake and retention of NIR dyes. Moreover, silencing HIF-1? by siRNA significantly decreased OATP mRNA expression and blocked NIR dye uptake in cancer cells. Together, these results demonstrated the preferential uptake of NIR dyes by canine and human cancer cells and tissues via the HIF-1?/OATPs signaling axis, which provides insights into future application of these dyes for cancer detection and treatment. PMID:25361418

  17. Pd nanoparticles supported on MIL-101/reduced graphene oxide photocatalyst: an efficient and recyclable photocatalyst for triphenylmethane dye degradation.

    PubMed

    Wu, Yan; Luo, Hanjin; Zhang, Li

    2015-11-01

    To improve the photocatalytic efficiency of chromium-based metal-organic framework (MIL-101) photocatalyst, Pd nanoparticles and reduced graphene oxide were used to modify the MIL-101 via a facile method. The resulting novel photocatalyst was characterized by UV-vis diffuse reflectance spectra (DRS), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). It was indicated that the photocatalyst afforded high photocatalytic efficiency for degradation of two triphenylmethane dyes, brilliant green and acid fuchsin, under exposure to visible light irradiation. Cyclic experiments demonstrated that the photocatalyst showed good reusability and stability for the dye degradation. PMID:26392090

  18. Efficient dye regeneration at low driving force achieved in triphenylamine dye LEG4 and TEMPO redox mediator based dye-sensitized solar cells.

    PubMed

    Yang, Wenxing; Vlachopoulos, Nick; Hao, Yan; Hagfeldt, Anders; Boschloo, Gerrit

    2015-06-28

    Minimizing the driving force required for the regeneration of oxidized dyes using redox mediators in an electrolyte is essential to further improve the open-circuit voltage and efficiency of dye-sensitized solar cells (DSSCs). Appropriate combinations of redox mediators and dye molecules should be explored to achieve this goal. Herein, we present a triphenylamine dye, LEG4, in combination with a TEMPO-based electrolyte in acetonitrile (E(0) = 0.89 V vs. NHE), reaching an efficiency of up to 5.4% under one sun illumination and 40% performance improvement compared to the previously and widely used indoline dye D149. The origin of this improvement was found to be the increased dye regeneration efficiency of LEG4 using the TEMPO redox mediator, which regenerated more than 80% of the oxidized dye with a driving force of only ?0.2 eV. Detailed mechanistic studies further revealed that in addition to electron recombination to oxidized dyes, recombination of electrons from the conducting substrate and the mesoporous TiO2 film to the TEMPO(+) redox species in the electrolyte accounts for the reduced short circuit current, compared to the state-of-the-art cobalt tris(bipyridine) electrolyte system. The diffusion length of the TEMPO-electrolyte based DSSCs was determined to be ?0.5 ?m, which is smaller than the ?2.8 ?m found for cobalt-electrolyte based DSSCs. These results show the advantages of using LEG4 as a sensitizer, compared to previously record indoline dyes, in combination with a TEMPO-based electrolyte. The low driving force for efficient dye regeneration presented by these results shows the potential to further improve the power conversion efficiency (PCE) of DSSCs by utilizing redox couples and dyes with a minimal need of driving force for high regeneration yields. PMID:26016854

  19. Dye-promoted precipitation of serum proteins. Mechanism and application.

    PubMed

    Birkenmeier, G; Kopperschläger, G

    1991-11-01

    Immobilized dyes have been used primarily for purification of nucleotide dependent enzymes and proteins from plasma and other sources. Due to their low costs, high protein binding capacity and resistance to degradation dyes bear the potential as ligand for affinity separation of proteins on a large scale. In this paper dyes have been used for precipitation of proteins. Using albumin, prealbumin, alpha 1-acid glycoprotein and immunoglobulin G as model proteins we could demonstrate that dye-promoted precipitation depends on several factors which include the structure of the dye, the pH of the solution, the dye/protein molar ratio and the intrinsic properties of the proteins. It revealed that most of the dyes tested were endowed with the precipitating potential. The efficacy of precipitation was found to increase with the complexity of the dye structure. However, the amount of a dye required for total precipitation was found to be different for a given protein. Electrostatic as well as hydrophobic forces are involved in the mechanism of precipitation. It was demonstrated that by optimizing the conditions, mixtures of proteins can be resolved by dye-promoted precipitation. The high sensitivity of the reaction offers the possibility of using this method for rapid concentration of very diluted protein solutions. PMID:1367693

  20. Dye lasing in optically manipulated liquid aerosols

    NASA Astrophysics Data System (ADS)

    Karadag, Yasin; Aas, Mehdi; Jonáš, Alexandr; Anand, Suman; McGloin, David; Kiraz, Alper

    2013-09-01

    We present dye lasing from optically manipulated glycerol-water aerosols with diameters ranging between 7.7 and 11.0 ?m confined in optical tweezers. While being optically trapped near the focal point of an infrared laser, the droplets stained with Rhodamine B were pumped with a Q-switched green laser and their fluorescence emission spectra featuring whispering gallery modes (WGMs) were recorded with a spectrograph. Nonlinear dependence of the intensity of the droplet WGMs on the pump laser fluence indicates dye lasing. The average wavelength of the lasing WGMs could be tuned between 600 and 630 nm by adjusting the droplet size. These results may lead to new ways of probing airborne particles, exploiting the high sensitivity of stimulated emission to small perturbations in the droplet laser cavity and the gain medium.

  1. Dye-Sensitized Approaches to Photovoltaics

    NASA Astrophysics Data System (ADS)

    Grätzel, Michael

    2008-03-01

    Sensitization of wide band-gap semiconductors to photons of energy less than the band-gap is a key step in two technically important processes - panchromatic photography and photoelectrochemical solar cells. In both cases the photosensitive species is not the semiconductor - silver halide or metal oxide - but rather an electrochemically active dye. The gap between the highest occupied molecular level (HOMO) and the lowest unoccupied molecular level (LUMO) is less than the band-gap of the semiconductor with which it is associated. It can therefore absorb light of a wavelength longer than that to which the semiconductor itself is sensitive. The electrochemical process is initiated when the dye molecule relaxes from its photoexcited level by electron injection into the semiconductor, which therefore acts as a photoanode. If the dye is in contact with a redox electrolyte, the negative charge represented by the lost electron can be recovered from the reduced state of the redox system, which in return is regenerated by charge transfer from a cathode. An external load completes the electrical circuit. The system therefore represents a conversion of the energy of absorbed photons into an electrical current by a regenerative device in every functional respect analogous to a solid-state photovoltaic cell. As in any engineering system, choice of materials, their optimization and their synergy are essential to efficient operation. While a semiconductor-electrolyte contact is analogous to a Schottky contact, in that a barrier is established between two materials of different conduction mechanism, with the possibility of optical absorption, charge carrier pair generation and separation, it should be remembered that the photogenerated valence band hole in the semiconductor represents a powerful oxidizing agent. Given that the band-gap is related to the strength and therefore the stability of chemical bonding within the semiconductor, for narrow-gap materials the most likely reaction of such a hole is the photocorrosion of the semiconductor itself. However, only relatively narrow band-gap materials have an effective optical absorption through the visible spectrum, towards and into the infra-red. Materials with an optimal band-gap match to the solar spectrum, of the order of 1.5eV, are therefore electrochemically unstable. A stable photoelectrochemical cell, without some process of optical sensitization, and necessarily using a wide-gap semiconductor is sensitive only to the ultra-violet limit of the visible spectrum. Over recent years a suitable combination of semiconductor and sensitizer has been identified and optimized, so that now a solar spectrum conversion efficiency of over 11% has been verified in a sensitized photoelectrochemical device. One key to such an efficient system is the suppression of recombination losses. When the excited dye relaxes by electron loss, the separated charge carriers find themselves on opposite sides of a phase barrier -- the electron within the solid-state semiconductor, the positive charge externally, in association with the dye molecule. There is no valence---band involvement in the process, so the system represents a majority-carrier device, avoiding one of the major loss mechanisms in conventional photovoltaics. In consequence also a highly-disordered, even porous, semiconductor structure is acceptable, enabling surface adsorption of a sufficient concentration of the dye to permit total optical absorption of incident light of photon energy greater than the HOMO-LUMO gap of the dye molecule. The accepted wide-band semiconductor for photoelectrochemical applications is titanium dioxide in the anatase crystal structure. The size of the nanocrystals making up the semiconductor photoanode can be determined by hydrothermal processing of a precursor sol, and the film can be deposited on a transparent conducting oxide (TCO) substrate by any convenient thin-film process such as screen printing or tape casting. The preferred dye system is inspired by the natural processes involving chlorophyll, the coloring

  2. A photoelectric amplifier as a dye detector

    USGS Publications Warehouse

    Ebel, Wesley J.

    1962-01-01

    A dye detector, based on a modified photoelectric amplifier, has been planned, built, and tested. It was designed to record automatically the time of arrival of fluorescein dye at predetermined points in a stream system. Laboratory tests and stream trials proved the instrument to be efficient. Small changes in color can be detected in turbid or clear water. The unit has been used successfully for timing intervals of more than 17 hours; significant savings of time and manpower have resulted. Replacement of the clock, included in the original device, with a recording milliammeter increases the efficiency of the unit by contin,!ously recording changes in turbidity. The addition of this component would increase the cost from $75 to approximately $105.

  3. Aza-BODIPY dyes with enhanced hydrophilicity.

    PubMed

    Kamkaew, Anyanee; Burgess, Kevin

    2015-07-01

    Attempts to make a diamino disulfonic acid derivative of an aza-BODIPY showed it was difficult to add BF2 to a disulfonated azadipyrromethene, and sulfonation of an aza-BODIPY resulted in loss of the BF2 fragment. We conclude the electron-deficient character of aza-BODIPY dyes destabilizes them relative to BODIPY dyes. Consequently, sulfonation of the aza-BODIPY core is not a viable strategy to increase water solubility. This assertion was indirectly supported via stability studies of a BODIPY and an aza-BODIPY in aqueous media. To afford the desired compound type, an aza-BODIPY with two amino and two sulfonic acid groups was prepared via modification of the aryl substituents with cysteic acid. PMID:26051677

  4. Anionic triphenylmethane dye solutions for low-dose food irradiation dosimetry

    NASA Astrophysics Data System (ADS)

    El-Assy, Nasef B.; Yun-Dong, Chen; Walker, M. L.; Al-Sheikhly, M.; McLaughlin, W. L.

    1995-09-01

    The radiolytic bleaching of aryl sulfonic-substituted para-diethyl-amino triphenylmethane dye solutions can be used for dosimetry in the absorbed dose range 10 to 400 Gy. The sulfonic anions provide solubility of these acid dyes in water. Two of these dyes are supplied as stable greenish-blue biological stains when dissolved in weakly-acidic aqueous solution, Light Green SF Yellowish and Fast Green FCF. They have, respectively, linear molar absorption coefficients of 7.14 × 103(at pH5.4) and 10.0 × 103 (at pH4.2) m2mol-1, when measured at the peaks of the primary absorption bands, 630 nm and 622 nm, respectively. The bleaching due to irradiation with gamma rays shows a linear function with a positive slope between the negative logarithm of the absorbance and the absorbed dose. The effect of pH on the response is studied, as well as the effects of light and temperature on pre- and post-irradiation stability. A mechanism, based mainly on radiolytic oxidation of the protonated phenolic or sulfonated phenyl group by .OH, with the abstraction of H-atom to water, is postulated for neutral to slightly acidic aerated aqueous solutions. The influence of alcohol on diminishing the negative yield is demonstrated. Alkaline aqueous solutions of these dyes (pH 10.2) have a shorter-wavelength absorption maximum than acidic aqueous solutions. The effect of irradiation is to cause acidification (to pH 7) due to displacement of OH groups and degradation of the dye molecule to lower molecular weight organic acids.

  5. Trinity Bay Study: Dye tracing experiments

    NASA Technical Reports Server (NTRS)

    Ward, G. H., Jr.

    1972-01-01

    An analysis of the heat balance and temperature distribution within Trinity Bay near Galveston, Texas is presented. The effects of tidal currents, wind driven circulations, and large volume inflows are examined. Emphasis is placed on the effects of turbulent diffusion and local shears in currents. The technique of dye tracing to determine the parameters characterizing dispersion is described. Aerial photographs and maps are provided to show the flow conditions existing at different times and seasons.

  6. Stretchable, wearable dye-sensitized solar cells.

    PubMed

    Yang, Zhibin; Deng, Jue; Sun, Xuemei; Li, Houpu; Peng, Huisheng

    2014-05-01

    A stretchable, wearable dye-sensitized solar-cell textile is developed from elastic, electrically conducting fiber as a counter electrode and spring-like titanium wire as the working electrode. Dyesensitized solar cells are demonstrated with energy-conversion efficiencies up to 7.13%. The high energy-conversion efficiencies can be well maintained under stretch by 30% and after stretch for 20 cycles. PMID:24648169

  7. Production of the Phanerochaete flavido-alba laccase in Aspergillus niger for synthetic dyes decolorization and biotransformation.

    PubMed

    Benghazi, Lamiae; Record, Eric; Suárez, Antonio; Gomez-Vidal, José A; Martínez, José; de la Rubia, Teresa

    2014-01-01

    We investigated the expression of Phanerochaete flavido-alba laccase gene in Aspergillus niger and the physical and biochemical properties of the recombinant enzyme (rLac-LPFA) in order to test it for synthetic dye biotransformation. A. niger was able to produce high levels of active recombinant enzyme (30 mgL(-1)), whose identity was further confirmed by immunodetection using Western blot analysis and N-terminal sequencing. Interestingly, rLac-LPFA exhibited an improved stability at pH (2-9) and organic solvents tested. Furthermore, the percentage of decoloration and biotransformation of synthetic textile dyes, Remazol Brilliant Blue R (RBBR) and Acid Red 299 (NY1), was higher than for the native enzyme. Its high production, simple purification, high activity, stability and ability to transform textile dyes make rLac-LPFA a good candidate for industrial applications. PMID:23884844

  8. [Peculiarity of pulsed dye laser lithotriptor and its clinical application].

    PubMed

    Matsumoto, T; Miki, M; Mamiya, Y; Hirata, T; Shimizu, H; Tochimoto, M; Ito, T; Aika, T

    1989-09-01

    Ultrasound lithotriptors (USL) and electrohydraulic lithotriptors (EHL) are representative lithotriptors for endoscopic elimination of upper urinary tract stones. However, they have some disadvantages. For example, USL can not be used with flexible scopes and EHL can cause unexpected tissue injury. To overcome these problems, the pulsed dye laser lithotriptor (MDL-1, Candera Co.) was developed. The characteristics of this laser lithotriptor and its direct effects on tissue was investigated. This pulsed dye laser lithotriptor generates a 504 nm wavelength green light beam by using a combination of a xenon flash lamp and the greenish dye composed of coumarin solution. The maximum output energy is 60 mJ/pulse and the pulse duration is 1.5 microsecond. The pulse rate can be varied from 1 to 20 Hz. First, the intensity of the shock wave was measured by using a combination of a piezoelectric element and an oscilloscope, and then, the results were compaired with those obtained by a similar experiment with an EHL. The average intensity of the shock wave was 54.4 mW under the conditions of 40 mJ/pulse of output energy and 10 Hz of pulse duration. On the other hand, the EHL generated an average of 54.7 W under the conditions of 400 mJ/pulse output energy. Then, fragmentation of various kinds of urinary stones in saline solution was performed. The results showed that this lithotriptor could fragment almost all kinds of stones except cystine stones. Then, hen's eggs were used to observe the effect if laser bean influenced on the organism immediately behind the photoradiated object. Only the egg shell was demolished but the egg membrane below the eggshell did not undergo any change. After these experiments, skin, liver, kidney and urinary bladder of nude mice and human prostatic urethral mucosa in case of TUR-P were irradiated by this laser. The results showed that laser energy caused slight penetration and localized hemorrhage from the surface of epithelium to subcutaneous tissue. It was confirmed that these effects were generated when the tip of the quartz fiber was in direct contact with the object.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2574247

  9. Decolorization of azo dyes by Geobacter metallireducens.

    PubMed

    Liu, Guangfei; Zhou, Jiti; Chen, Congcong; Wang, Jing; Jin, Ruofei; Lv, Hong

    2013-09-01

    Geobacter metallireducens was found to be capable of decolorizing several azo dyes with different structures to various extents. Pyruvate, ethanol, acetate, propionate, and benzoate could support 66.3?±?2.6-93.7?±?2.1 % decolorization of 0.1 mM acid red 27 (AR27) in 40 h. The dependence of the specific decolorization rate on AR27 concentration (25 to 800 ?M) followed Michaelis-Menten kinetics (K m?=?186.9?±?1.4 ??, V max?=?0.65?±?0.02 ?mol?mg protein(-1) h(-1)). Enhanced AR27 decolorization was observed with the increase of cell concentrations ranging from 7.5 to 45 mgL(-1). AR27 decolorization by G. metallireducens was retarded by the presence of goethite, which competed electrons with AR27 and was reduced to Fe(II). The addition of low concentrations of humic acid (1-100 mgL(-1)) or 2-hydroxy-1,4-naphthoquinone (0.5-50 ?M) could improve the decolorization performance of G. metallireducens. High-performance liquid chromatography analysis suggested reductive pathway to be responsible for decolorization. This was the first study on azo dye decolorization by Geobacter strain and might improve our understanding of natural attenuation and bioremediation of environments polluted by azo dyes. PMID:23132348

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

    DOEpatents

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

    1993-10-26

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

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

    EPA Science Inventory

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

  12. Rational molecular engineering of cyclopentadithiophene-bridged D-A-?-A sensitizers combining high photovoltaic efficiency with rapid dye adsorption

    PubMed Central

    Chai, Qipeng; Li, Wenqin; Liu, Jingchuan; Geng, Zhiyuan; Tian, He; Zhu, Wei-hong

    2015-01-01

    Dye-sensitized solar cell (DSSC) is considered as a feasible route to the clean and renewable energy conversion technique. The commercial application requires further enhancements on photovoltaic efficiency and simplification on the device fabrication. For avoiding the unpreferable trade-off between photocurrent (JSC) and photovoltage (VOC), here we report the molecular engineering and comprehensive photovoltaic characterization of three cyclopentadithiophene-bridged D-A-?-A motif sensitizers with a change in donor group. We make a careful choice on the donor and conjugation bridge for synergistically increasing JSC and VOC. Comparing with the reference dye WS-2, the photovoltaic efficiency with the single component dye of WS-51 increases by 18%, among one of the rare examples in pure metal-free organic dyes exceeding 10% in combination with traditional iodine redox couples. Moreover, WS-51 exhibits several prominent merits on potentially scale-up industrial application: i) facile synthetic route to target molecule, ii) simple dipping procedure without requirement of co-sensitization, and iii) rapid dye adsorption capability. PMID:26066974

  13. Rational molecular engineering of cyclopentadithiophene-bridged D-A-?-A sensitizers combining high photovoltaic efficiency with rapid dye adsorption

    NASA Astrophysics Data System (ADS)

    Chai, Qipeng; Li, Wenqin; Liu, Jingchuan; Geng, Zhiyuan; Tian, He; Zhu, Wei-Hong

    2015-06-01

    Dye-sensitized solar cell (DSSC) is considered as a feasible route to the clean and renewable energy conversion technique. The commercial application requires further enhancements on photovoltaic efficiency and simplification on the device fabrication. For avoiding the unpreferable trade-off between photocurrent (JSC) and photovoltage (VOC), here we report the molecular engineering and comprehensive photovoltaic characterization of three cyclopentadithiophene-bridged D-A-?-A motif sensitizers with a change in donor group. We make a careful choice on the donor and conjugation bridge for synergistically increasing JSC and VOC. Comparing with the reference dye WS-2, the photovoltaic efficiency with the single component dye of WS-51 increases by 18%, among one of the rare examples in pure metal-free organic dyes exceeding 10% in combination with traditional iodine redox couples. Moreover, WS-51 exhibits several prominent merits on potentially scale-up industrial application: i) facile synthetic route to target molecule, ii) simple dipping procedure without requirement of co-sensitization, and iii) rapid dye adsorption capability.

  14. Rational molecular engineering of cyclopentadithiophene-bridged D-A-?-A sensitizers combining high photovoltaic efficiency with rapid dye adsorption.

    PubMed

    Chai, Qipeng; Li, Wenqin; Liu, Jingchuan; Geng, Zhiyuan; Tian, He; Zhu, Wei-Hong

    2015-01-01

    Dye-sensitized solar cell (DSSC) is considered as a feasible route to the clean and renewable energy conversion technique. The commercial application requires further enhancements on photovoltaic efficiency and simplification on the device fabrication. For avoiding the unpreferable trade-off between photocurrent (JSC) and photovoltage (VOC), here we report the molecular engineering and comprehensive photovoltaic characterization of three cyclopentadithiophene-bridged D-A-?-A motif sensitizers with a change in donor group. We make a careful choice on the donor and conjugation bridge for synergistically increasing JSC and VOC. Comparing with the reference dye WS-2, the photovoltaic efficiency with the single component dye of WS-51 increases by 18%, among one of the rare examples in pure metal-free organic dyes exceeding 10% in combination with traditional iodine redox couples. Moreover, WS-51 exhibits several prominent merits on potentially scale-up industrial application: i) facile synthetic route to target molecule, ii) simple dipping procedure without requirement of co-sensitization, and iii) rapid dye adsorption capability. PMID:26066974

  15. Studies on Dyeing Process Variables for Salt Free Reactive Dyeing of Glycine Modified Cationized Cotton Muslin Fabric

    NASA Astrophysics Data System (ADS)

    Samanta, Ashis Kumar; Kar, Tapas Ranjan; Mukhopadhyay, Asis; Shome, Debashis; Konar, Adwaita

    2015-04-01

    Bleached cotton muslin fabric with or without pre-oxidized with NaIO4 (oxy-cotton) was chemically modified with glycine (amino acid) by pad dry calendar process to investigate the changes in textile properties and its dyeability with reactive dye. This glycine modified cotton incorporates new functional groups producing -NH3 + or -C=NH+ -ion (cationic groups) in acid bath to obtain cationized cotton making it amenable to a newer route of salt free reactive dyeing in acid bath. In the present work the process variables of reactive dyeing in the salt free acid bath for dyeing of amine (glycine) modified cationized cotton were studied and optimized. The present study also includes thorough investigation of changes in important textile related properties and dyeability with reactive dye after such chemical modifications. Between oxidized and unoxidized cotton muslin fabric, unoxidized cotton fabric shows better reactive dye uptake in both conventional alkaline bath dyeing and nonconventional salt free acid bath dyeing particularly for high exhaustion class of reactive dye with acceptable level of colour fastness and overall balance of other textile related properties. Moreover, application of dye fixing agent further improves surface colour depth (K/S) of the glycine treated cotton fabric for HE brand of reactive dyes. Corresponding reaction mechanisms for such modifications were supported by FTIR spectroscopy. Finally unoxidized cotton and pre-oxidized cotton further treated with glycine (amino acid) provide a new route of acid bath salt free reactive dyeing showing much higher dye uptake and higher degree of surface cover with amino acid residue anchored to modified cotton.

  16. Investigating Fluorescence Dyes in Fluorescence-Assisted Screenings

    PubMed Central

    Jee, Joo-Eun; Lim, Jaehong; Hyun, Hoon; Oon, Jessica; Ong, Yong Siang; Massif, Cedrik; Chang, Young-Tae; Choi, Hak Soo; Lee, Su Seong

    2014-01-01

    Screening of bead-based peptide libraries against fluorescence-labeled target proteins was found significantly influenced by the dye characteristics. Commercially available red fluorescence dyes with net negative charges adversely showed strong interactions with library beads. The introduction of zwitterionic dyes significantly reduced the unwanted interactions, which sheds light upon using the right fluorescence probe for acquisition of reliable results in various fluorescence-assisted applications. PMID:25340456

  17. Effect of an azo dye on the performance of an aerobic granular sludge sequencing batch reactor treating a simulated textile wastewater.

    PubMed

    Franca, Rita D G; Vieira, Anabela; Mata, Ana M T; Carvalho, Gilda S; Pinheiro, Helena M; Lourenço, Nídia D

    2015-11-15

    This study analyzed the effect of an azo dye (Acid Red 14) on the performance of an aerobic granular sludge (AGS) sequencing batch reactor (SBR) system operated with 6-h anaerobic-aerobic cycles for the treatment of a synthetic textile wastewater. In this sense, two SBRs inoculated with AGS from a domestic wastewater treatment plant were run in parallel, being one supplied with the dye and the other used as a dye-free control. The AGS successfully adapted to the new hydrodynamic conditions forming smaller, denser granules in both reactors, with optimal sludge volume index values of 19 and 17 mL g(-1) after 5-min and 30-min settling, respectively. As a result, high biomass concentration levels and sludge age values were registered, up to 13 gTSS L(-1) and 40 days, respectively, when deliberate biomass wastage was limited to the sampling needs. Stable dye removal yields above 90% were attained during the anaerobic reaction phase, confirmed by the formation of one of the aromatic amines arising from azo bond reduction. The control of the sludge retention time (SRT) to 15 days triggered a 30% reduction in the biodecolorization yield. However, the increase of the SRT values back to levels above 25 days reverted this effect and also promoted the complete bioconversion of the identified aromatic amine during the aerobic reaction phase. The dye and its breakdown products did not negatively affect the treatment performance, as organic load removal yields higher than 80% were attained in both reactors, up to 77% occurring in the anaerobic phase. These high anaerobic organic removal levels were correlated to an increase of Defluviicoccus-related glycogen accumulating organisms in the biomass. Also, the capacity of the system to deal with shocks of high dye concentration and organic load was successfully demonstrated. Granule breakup after long-term operation only occurred in the dye-free control SBR, suggesting that the azo dye plays an important role in improving granule stability. Fluorescence in situ hybridization (FISH) analysis confirmed the compact structure of the dye-fed granules, microbial activity being apparently maintained in the granule core, as opposed to the dye-free control. These findings support the potential application of the AGS technology for textile wastewater treatment. PMID:26343991

  18. Approach to a two-step process of dye wastewater containing acid red B.

    PubMed

    Xiong, Y; Karlsson, H T

    2001-01-01

    The treatment of simulated wastewater containing Acid Scarlet BS was tested with a two-step process that the pretreatment of Fe(II)-mediated decolorization was followed by the electrochemical oxidation with a three-phase three-dimensional electrodes. The experimental results showed that the decolorization mechanism was reductive destruction for the azo group of the dye molecular rather than flocculation or absorption and that the three-phase three-dimensional electrode can effectively reduce COD in the decolorized wastewater simultaneously by several mechanisms such as absorption, air-oxidation, anodic oxidation, cathodic electrogenerated H2O2 and so on. It was also observed that COD for the decolorized wastewater was easier removed as compared with the original dye wastewater, implying that the first and second stage act synergistically to destroy the organic pollutants. PMID:11360443

  19. Observation of precursorlike behavior of femtosecond pulses in a dye with a strong absorption band

    SciTech Connect

    Springer, Matthew M.; Yang Wenlong; Kolomenski, Alexandre A.; Schuessler, Hans A.; Strohaber, James; Kattawar, George W.; Sokolov, Alexei V.

    2011-04-15

    Recent interest in Sommerfeld-Brillouin optical precursors has brought attention to the possibility of optical precursor observation in bulk matter. We investigate the possible formation of optical precursors in an organic dye solution with a sharp absorption band and anomalous dispersion at a wavelength of approximately 800 nm. We explore this regime experimentally with sub-10-fs pulses with a central wavelength of approximately 800 nm from a Ti : sapphire oscillator. The pulses are passed through a thin layer of the dye solution and characterized by interferometric autocorrelation. The obtained autocorrelation traces are compared with simulations, and we observe important dispersion effects on the shape of the propagated pulses, including precursorlike behavior in their time evolution.

  20. Nonlinear absorption and upconversion properties of two-photon absorption dye: ASPI

    NASA Astrophysics Data System (ADS)

    Wang, Dong; Zhou, Guangyong; Xu, Xinguang; Wang, Xiaomei; Liu, Zhiqiang; Ren, Yan; Shao, Zongshu; Jiang, Minhua

    2002-02-01

    Two-photon absorption (TPA) cross sections of an organic dye, trans-4-[ p-( N-hydroxyethyl- N-methylamino)tyryl]- N-methylpyridinium iodide (abbreviated as ASPI), from 720 to 1100 nm have been measured by using nonlinear transmittance method, which reflect the TPA degrees of the dye at different wavelengths. The maximum TPA wavelength is located at 930 nm. The upconversion efficiencies of ASPI in dimethyl formamide and benzyl alcohol at different pump wavelengths have also been measured. There is 90 nm red shift for the highest upconversion wavelength as comparing with the strongest TPA wavelength. The influences of the solvents on the TPA-induced emission spectrum and the conversion efficiencies have also been given.