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1

Simulation of indigo carmine dye adsorption on polymer doped sawdust in fixed-bed systems  

Microsoft Academic Search

This research analyzes the potential use of polyaniline doped sawdust (PANI\\/SD) as a low-cost adsorbent to remove indigo carmine (IC) from aqueous solutions in a continuous fixed-bed system. The effects of inlet dye flow rate, concentration and bed height on the breakthrough characteristics of the adsorption system were determined. The breakthrough time and saturation time increased with decreases in the

Deli Liu; Dezhi Sun

2011-01-01

2

Effects of dyes (indigo carmine, metanil yellow, fast green FCF) and nitrite in vivo on bone marrow chromosomes of mice.  

PubMed

Effects of 3 dyes in combination with nitrite were studied on bone marrow chromosomes of mice following prolonged oral treatment. The dyes were namely, Indigo Carmine and Metanil Yellow, both of which contain a secondary amino group, and Fast Green FCF, which has a tertiary amino group. All dyes produced aberrations but Metanil Yellow showed stronger clastogenic activity than Fast Green FCF and Indigo Carmine. Nitrite alone also induced strong clastogenic activity. A combination of dye and nitrite half the normal concentrations produced synergistic effects, which may be ascribed to the formation of nitrosamines. PMID:3697949

Giri, A K; Banerjee, T S; Talukder, G; Sharma, A

1986-03-01

3

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

PubMed

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

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

2012-05-30

4

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

PubMed Central

Using sodium, instead of lithium, in rechargeable batteries is a way to circumvent the lithium's resource problem. The challenge is to find an electrode material that can reversibly undergo redox reactions in a sodium-electrolyte at the desired electrochemical potential. We proved that indigo carmine (IC, 5,5?-indigodisulfonic acid sodium salt) can work as a positive-electrode material in not only a lithium-, but also a sodium-electrolyte. The discharge capacity of the IC-electrode was ~100?mAh g?1 with a good cycle stability in either the Na or Li electrolyte, in which the average voltage was 1.8?V vs. Na+/Na and 2.2?V vs. Li+/Li, respectively. Two Na ions per IC are stored in the electrode during the discharge, testifying to the two-electron redox reaction. An X-ray diffraction analysis revealed a layer structure for the IC powder and the DFT calculation suggested the formation of a band-like structure in the crystal. PMID:24413423

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

2014-01-01

5

Trans-spectral organic dye laser photocoagulation.  

PubMed

Clinical research utilizing the yellow, orange, and red wavelengths of the dye laser (Rhodamine 6G and MD-631) appears to have considerable promise and may demonstrate that the liquid organic dye laser is the laser of choice for photocoagulation of many types of ocular defects. The effectiveness of the dye laser as a photocoagulation source is due to the trans-spectral availability of relatively high output power wavelengths. Therefore, a target tissue can be selectively coagulated with minimal laser energy transmitted through the refractive media and minimal damage to nearby normal tissues. The dye laser, as a photocoagulation system, should prove valuable in the therapy of many ocular diseases. PMID:2421474

L'Esperance, F A

1985-01-01

6

Organic dyes incorporating oligothienylenevinylene for efficient dye-sensitized solar cells.  

PubMed

Two new organic dyes incorporating triphenylamine as a donor and oligothienylenevinylene as a bridge have been synthesized. The new dyes cover the entire visible region and have a power conversion of up to 6.25%. PMID:23134213

Aljarilla, Ana; López-Arroyo, Leticia; de la Cruz, Pilar; Oswald, Frederic; Meyer, Toby B; Langa, Fernando

2012-11-16

7

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2010 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...amounts consistent with good manufacturing practices. (c) Labeling. The color additive and any mixture...

2010-04-01

8

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2011 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling . (1) The color additive and any mixture...

2011-04-01

9

21 CFR 73.2087 - Carmine.  

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling. (1) The color additive and any mixture...

2014-04-01

10

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2013 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling . (1) The color additive and any mixture...

2013-04-01

11

21 CFR 73.2087 - Carmine.  

Code of Federal Regulations, 2012 CFR

...GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION...specifications. The color additive carmine shall conform...consistent with good manufacturing practices. (c) Labeling . (1) The color additive and any mixture...

2012-04-01

12

The J- and H-bands of organic dye aggregates  

NASA Astrophysics Data System (ADS)

Certain molecular aggregates consisting of organic dyes are remarkable in exhibiting an intense and very narrow absorption peak, known as a J-band, which is red-shifted away from the region of monomer absorption. Apart from those dyes showing the J-band on aggregation, there are also dyes where the absorption maximum is shifted to higher energies. The width of the resulting absorption band (called an H-band) is comparable to that of the monomeric dyes and shows a complicated vibrational structure. Following our analysis of the J-band spectra of polymer aggregates using the CES approximation [A. Eisfeld, J.S. Briggs, Chem. Phys. 281 (2002) 61], a theory that includes vibrations explicitly, we show that the same approximation can account for measured H-band spectra. Using simple analytical forms of the monomer spectrum the origin of the widely different shapes of H- and J-bands is explained within the CES approximation.

Eisfeld, A.; Briggs, J. S.

2006-05-01

13

Co-sensitization of organic dyes for efficient dye-sensitized solar cells.  

PubMed

Novel cyanine dyes, in which a tetrahydroquinoline derivative is used as an electron donor and 1-butyl-5-carboxy-3, 3-dimethyl-indol-1-ium moiety is used as an electron acceptor and anchoring group, were designed and synthesized for application in dye-sensitized solar cells. The photovoltaic performance of these solar cells depends markedly on the molecular structure of the dyes in terms of the n-hexyl chains and the methoxyl unit. Retardation of charge recombination caused by the introduction of n-hexyl chains resulted in an increase in electron lifetime. As a consequence, an improvement of open-circuit photovoltage (V(oc)) was achieved. Also, the electron injection efficiencies were improved by the introduction of methoxyl moiety, which led to a higher short-circuit photocurrent density (J(sc)). The highest average efficiency of the sensitized devices (?) was 5.6% (J(sc)=13.3 mA cm(-2), V(oc)=606 mV, and fill factor FF=69.1%) under 100 mW cm(-2) (AM 1.5G) solar irradiation. All of these dyes have very high absorption extinction coefficients and strong absorption in a relatively narrow spectrum range (500-650 nm), so one of our organic dyes was explored as a sensitizer in co-sensitized solar cells in combination with the other two other existing organic dyes. Interestingly, a considerably improved photovoltaic performance of 8.2% (J(sc)=20.1 mA cm(-2), V(oc)=597 mV, and FF=68.3%) was achieved and the device showed a panchromatic response with a high incident photon-to-current conversion efficiency exceeding 85% in the range of 400-700 nm. PMID:23193040

Cheng, Ming; Yang, Xichuan; Li, Jiajia; Zhang, Fuguo; Sun, Licheng

2013-01-01

14

Ultra-high-performance liquid chromatography/tandem high-resolution mass spectrometry analysis of sixteen red beverages containing carminic acid: identification of degradation products by using principal component analysis/discriminant analysis.  

PubMed

The study investigates the sunlight photodegradation process of carminic acid, a natural red colourant used in beverages. For this purpose, both carminic acid aqueous standard solutions and sixteen different commercial beverages, ten containing carminic acid and six containing E120 dye, were subjected to photoirradiation. The results show different patterns of degradation, not only between the standard solutions and the beverages, but also from beverage to beverage. Due to the different beverage recipes, unpredictable reactions take place between the dye and the other ingredients. To identify the dye degradation products in a very complex scenario, a methodology was used, based on the combined use of principal component analysis with discriminant analysis and ultra-high-performance liquid chromatography coupled with tandem high resolution mass spectrometry. The methodology is unaffected by beverage composition and allows the degradation products of carminic acid dye to be identified for each beverage. PMID:25149011

Gosetti, Fabio; Chiuminatto, Ugo; Mazzucco, Eleonora; Mastroianni, Rita; Marengo, Emilio

2015-01-15

15

Holograms recorded in organic dye sensitized dichromate gelatin  

NASA Astrophysics Data System (ADS)

Experimental techniques are described for recording holograms in dichromate gelatin doped with an organic dye. This material has excellent resolution, and increase the photo sensibility. We present some basic studies about the possible form of to storage information, and reported results. This material is cheap, easy of to use, and it decrease the register time.

Páez-Trujillo, G.; Olivares-Pérez, A.; Mejias-Brizuela, N.; Garay-Hernández, M. P.; Fontanilla-Urdaneta, R.; Fuentes-Tapia, I.; Amigón-De León, E.

2007-09-01

16

Theoretical investigation of phenothiazine-triphenylamine-based organic dyes with different ? spacers for dye-sensitized solar cells.  

PubMed

Three phenothiazine-triphenylamine-based organic dyes (CD-1, CD-2 and CD-3) are designed based on the dye WD-8. The geometries, electronic structures, and electronic absorption spectra of these dyes before and after binding to TiO2 are studied by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The calculated geometries indicate that these dyes show good steric hindrance effect which is advantage to inhibit the close intermolecular ?-? aggregation effectively. The lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels of these dyes could ensure positive effect on the process of electron injection and dye regeneration. The simulated spectra of CD-1?3 show better absorption than that of WD-8 in the low energy zone. All the calculated results demonstrate that these dyes could be used as potential sensitizers for DSSCs and show better performances than WD-8. PMID:24398472

Chen, Ximing; Jia, Chunyang; Wan, Zhongquan; Zhang, Jiaqiang; Yao, Xiaojun

2014-04-01

17

Organics Verification Study for Sinclair and Dyes Inlets, Washington  

SciTech Connect

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

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

2006-09-28

18

Reduced lasing threshold from organic dye microcavities  

E-print Network

We demonstrate an unexpected tenfold reduction in the lasing threshold of an organic vertical microcavity under subpicosecond optical excitation. In contrast to conventional theory of lasing, we find that the lasing threshold ...

Akselrod, G. M.

19

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

PubMed Central

Background There is growing evidence that indigo carmine chromoendoscopy is effective for the in vivo diagnosis of colonic polyps. However, the impact of colonoscope resolution on diagnostic accuracy has not been investigated. Objective We aimed to compare the effectiveness of in vivo diagnosis of small colonic polyps using indigo carmine dye spray with standard-definition and high-definition colonoscopes. Methods Procedures were performed using Fujinon colonoscopes and EPX 4400 processor. Fujinon standard-definition (SD) and high-definition (HD) colonoscopes were used, with the endoscopist blinded to colonoscope definition. Polyps <10?mm were assessed using 0.2% indigo carmine dye spray, with the predicted diagnosis recorded. In each case the kind of colonoscope (SD or HD) was recorded. Polyps were removed and sent for histological analysis, with the pathologist blinded to the diagnosis made by the endoscopist. The predicted diagnosis was compared with the true histology to calculate the accuracy, sensitivity and specificity of in vivo assessment using either SD or HD scopes. Results In total 237 polyps <10?mm in size were examined. There was no statistically significant difference for any of the measured parameters between SD and HD assessments, with an accuracy, sensitivity and specificity of 89%, 91% and 87% with SD colonoscopes and 92%, 96% and 84% with HD colonoscopes. Conclusions The accuracy of in vivo assessment of small colonic polyps with indigo carmine dye spray is excellent with standard-definition colonoscopes and is not improved with high-definition colonoscopes. PMID:24917993

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

2013-01-01

20

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

NASA Astrophysics Data System (ADS)

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

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

2014-11-01

21

Influence of iron on degradation of organic dyes in corona.  

PubMed

In this work application of AOPs such as Fenton process, aqueous phase high voltage electrical discharge (corona) and their combination have been studied for colored wastewater treatment. Experiments were conducted on water solutions of four different organic dyes, two azo dyes C.I. Mordant Yellow 10 (MY10) and C.I. Direct Orange 39 (DO39), and two reactive of azo type C.I. Reactive Red 45 (RR45) and C.I. Reactive Blue 137 (RB137). The efficiency of studied AOPs has been estimated on the bases of UV-vis spectrophotometric and TOC measurements. The rate constants in the kinetic model have been determined. Experimental data have been compared with the developed mathematical model. PMID:15629569

Koprivanac, Natalija; Kusi?, Hrvoje; Vujevi?, Dinko; Peternel, Igor; Locke, Bruce R

2005-01-31

22

Triphenylamine-based organic dyes with julolidine as the secondary electron donor for dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Two novel donor-donor-?-conjugated-acceptor (D-D-?-A) metal-free organic dyes (JTPA1 and JTPA2) with a julolidine moiety as the secondary electron donor for dye-sensitized solar cells (DSSCs) are synthesized. Their absorption spectra, electrochemical and photovoltaic properties are extensively investigated and compared with TPA2 dye. Transient absorption measurements show that both sensitizers are quickly regenerated and the dye cations are efficiently intercepted by the redox mediator. Both dyes show good performance as DSSC photosensitizers. In particular, a DSSC using JTPA2 with rhodanine-3-acetic acid shows better photovoltaic performance with a short-circuit photocurrent density (Jsc) of 9.30 mA cm-2, an open-circuit photovoltage (Voc) of 509 mV and a fill factor (FF) of 0.68, corresponding to an overall conversion efficiency (?) of 3.2% under AM 1.5 irradiation (100 mW cm-2). Under similar test conditions, ruthenium-based N719 dye gives an efficiency of 6.7%. Compared to TPA2, the dye regeneration rate, the short-circuit photocurrent density and the conversion efficiency of JTPA2 are doubled by introducing a julolidine unit. Our findings show that the julolidine unit may be an excellent electron donor system for organic dyes harvesting solar irradiation.

Wu, Guohua; Kong, Fantai; Li, Jingzhe; Fang, Xiaqin; Li, Yi; Dai, Songyuan; Chen, Qianqian; Zhang, Xianxi

2013-12-01

23

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...

24

Meta versus para substituent effect of organic dyes for sensitized solar cells  

Microsoft Academic Search

A series of new metal-free organic donor-bridge-acceptor dyes comprising a triphenylamine moiety as the electron donor, and a cyanoacrylic acid (dye series A) or a carboxylic acid moiety (dye series B) as the electron acceptor were synthesized and utilized for dye-sensitized solar cells (DSSCs). The triphenylamine moiety was linked to the main chromophore through either a para or a meta

Yan-Duo Lin; Ching-Ting Chien; Szu-Yu Lin; Heng-Hsuan Chang; Ching-Yang Liu; Tahsin J. Chow

2011-01-01

25

Brazil nut shells as a new biosorbent to remove methylene blue and indigo carmine from aqueous solutions.  

PubMed

The adsorption of methylene blue and indigo carmine, respectively a basic and an acid dye, was studied on raw Brazil nut shells. The dye removal from solution by BNS was governed by: (i) polarization effects between the colored ions and the surface sites, leading to physisorbed species due to weak electrostatic forces and (ii) diffusion limitations affecting the kinetic parameters. Thermodynamic studies showed that the adsorption of methylene blue and of indigo carmine was spontaneous and exothermic occurring with entropy decrease. H(0) values confirmed the physical nature of the adsorption processes. The adsorption followed the Langmuir model and pseudo-second order kinetics over the entire range of tested concentrations but the process was controlled by intraparticle diffusion. The maximal uptakes were 7.81 mg g(-1), for methylene blue, and 1.09 mg g(-1) for indigo carmine, at room temperature. These results indicate that Brazil nut shells may be useful as adsorbent either for basic or acid dyes. PMID:19781853

de Oliveira Brito, Suzana Modesto; Andrade, Heloysa Martins Carvalho; Soares, Luciana Frota; de Azevedo, Rafael Pires

2010-02-15

26

Catalytic degradation of organic dyes using biosynthesized silver nanoparticles.  

PubMed

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

Vidhu, V K; Philip, Daizy

2014-01-01

27

Case study on the destruction of organic dyes in supercritical water  

SciTech Connect

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

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

1994-11-01

28

A novel amine-free dianchoring organic dye for efficient dye-sensitized solar cells.  

PubMed

An amine-free oligothiophene-based dye (BTB) featuring a tailor-made dianchoring function, a spiro-configured central unit, and bulky end-capping TIPS groups to diminish intermolecular interactions and to suppress aggregation-induced self-quenching was synthesized to achieve efficient dye-sensitized solar cells with a high power conversion efficiency of 6.52%. PMID:23215150

Ting, Hao-Chun; Tsai, Chih-Hung; Chen, Jia-Hong; Lin, Li-Yen; Chou, Shu-Hua; Wong, Ken-Tsung; Huang, Tsung-Wei; Wu, Chung-Chih

2012-12-21

29

Organic dyes with intense light absorption especially suitable for application in thin-layer dye-sensitized solar cells.  

PubMed

Three new thiazolo[5,4-d]thiazole-based organic dyes have been designed and synthesized for employment as DSSC sensitizers. Alternation of the electron poor thiazolothiazole unit with two propylenedioxythiophene (ProDOT) groups ensured very intense light absorption in the visible region (? up to 9.41 × 10(4) M(-1) cm(-1) in THF solution). The dyes were particularly suitable for application in transparent and opaque thin-layer DSSCs (TiO2 thickness: 5.5-6.5 ?m, efficiencies up to 7.71%), thus being good candidates for production of solar cells under simple fabrication conditions. PMID:25264863

Dessì, Alessio; Calamante, Massimo; Mordini, Alessandro; Peruzzini, Maurizio; Sinicropi, Adalgisa; Basosi, Riccardo; Fabrizi de Biani, Fabrizia; Taddei, Maurizio; Colonna, Daniele; Di Carlo, Aldo; Reginato, Gianna; Zani, Lorenzo

2014-10-16

30

Degradation of wastewaters containing organic dyes photocatalysed by zinc oxide: a review  

Microsoft Academic Search

Organic dyes are one of the largest groups of pollutants discharged into wastewaters from textile and other industrial processes. Owing to the potential toxicity of the dyes and their visibility in surface waters, removal and degradation of them have attracted considerable attention worldwide. A wide range of approaches have been developed, amongst which the heterogeneous photocatalysis involving zinc oxide (ZnO)

Sze-Mun Lam; Jin-Chung Sin; Ahmad Zuhairi Abdullah; Abdul Rahman Mohamed

2012-01-01

31

21 CFR 73.1100 - Cochineal extract; carmine.  

Code of Federal Regulations, 2010 CFR

...mixtures for coloring drugs. (b) Uses and restrictions. Cochineal extract and carmine may be safely used for coloring ingested and externally applied drugs in amounts consistent with good manufacturing practice. (c) Labeling requirements....

2010-04-01

32

Assessment of the ?SCF-DFT approach for electronic excitations in organic dyes  

E-print Network

This paper assesses the accuracy of the ?SCF method for computing low-lying HOMO?LUMO transitions in organic dye molecules. For a test set of vertical excitation energies of 16 chromophores, surprisingly similar accuracy ...

Kowalczyk, Timothy Daniel

33

Study of porous silicon optical waveguides impregnated with organic dyes  

NASA Astrophysics Data System (ADS)

Planar waveguides were made using oxidised porous silicon layers. Then, they were impregnated with Congo Red or Disperse Red 1 dyes. Optical losses were investigated before and after impregnation. In our case, the losses of impregnated waveguides were always higher than those of non-impregnated ones. In order to achieve a better understanding of the origin of these losses, we not only studied the absorbance of solutions which would impregnate the porous layers but also the reflectance spectra of the obtained composite materials. According to the measurements, the increase in losses in the visible spectrum depends on the intrinsic absorption of the dye while in NIR, the increase would be due to an accumulation of dried dye on the surface of the waveguide which would give rise to the surface scattering losses.

Pirasteh, P.; Charrier, J.; Dumeige, Y.; Chaillou, A.; Guendouz, M.; Haji, L.

2007-01-01

34

Design of an organic chromophore for p-type dye-sensitized solar cells.  

PubMed

A successful model for the design of efficient dyes for p-type dye-sensitized solar cells (DSSCs) is presented. As an example, a novel and efficient organic dye containing a triphenylamine chromophore has been synthesized and successfully applied in a p-type DSSC. The highest incident photon-to-current conversion efficiency (IPCE) of 18% in the visible region has been obtained, which is the highest value so far in p-type DSSCs. This is remarkably high, considering that only 600 nm thin NiO mesoporous films were used as p-type DSSC electrodes. PMID:18553967

Qin, Peng; Zhu, Hongjun; Edvinsson, Tomas; Boschloo, Gerrit; Hagfeldt, Anders; Sun, Licheng

2008-07-01

35

A luminescent dye@MOF platform: emission fingerprint relationships of volatile organic molecules.  

PubMed

Self-assembly of luminescent moieties into porous metal-organic frameworks (MOFs) has generated many luminescent platforms for probing volatile organic molecules (VOMs). However, most of those explored thus far have only been based on the luminescence intensity of one transition, which is not efficient for probing different VOMs. We have synthesized a luminescent MOF material containing 1D nanotube channels, and further developed a luminescent dye@MOF platform to realize the probing of different VOMs by tuning the energy transfer efficiency between two different emissions. The dye@MOF platform exhibits excellent fingerprint correlation between the VOM and the emission peak-height ratio of ligand to dye moieties. The dye@MOF sensor is self-calibrating, stable, and instantaneous, thus the approach should be a very promising strategy to develop luminescent materials with unprecedented practical applications. PMID:24382789

Dong, Ming-Jie; Zhao, Min; Ou, Sha; Zou, Chao; Wu, Chuan-De

2014-02-01

36

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

Microsoft Academic Search

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

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

1992-01-01

37

Effects of certain food dyes on chromosomes of Allium cepa.  

PubMed

The effects of 4 permitted food dyes, i.e., fast green FCF, indigo carmine, orange G and tartrazine, and the non-permitted dye metanil yellow on chromosomes of Allium cepa are reported. A significant increase in polyploid cells was observed in all cases. High doses of these dyes induced chromosome breaks and micronucleus formation. Although all dyes produced mitotic aberrations, metanil yellow and fast green FCF showed comparatively stronger clastogenic activity. PMID:2739686

Roychoudhury, A; Giri, A K

1989-07-01

38

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

E-print Network

Local tuning of organic light-emitting diode color by dye droplet application T. R. Hebner and J. C is the realization of full color flat panel displays. OLEDs are attractive because of their potential to be used integration. Patterning and etching of organics is difficult using photoresist and standard semi- conductor

39

Insights into the co-sensitizer adsorption kinetics for complementary organic dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Co-sensitization is a well-known method to broaden the light absorption wavelength. The co-sensitizer adsorption kinetics in dye-sensitized solar cells (DSSCs) is investigated by using simple UV-visible absorption spectra and images for co-sensitizers before and after TiO2 films soaking. The adsorption rate and surface coverage on TiO2 films of the co-sensitizers, i.e., a metal-free squaraine dye (SQ2) and a diarylaminofluorene-based organic dye (JD1), are also studied to explain the performance of DSSCs. The power conversion efficiency (?) of the co-sensitized DSSC is enhanced due to the cooperative interactions of the organic co-sensitizers. A wide absorption wavelength (400-750 nm) for light harvesting is found for the co-sensitizer at the molar ratio of 6 to 4 for JD1 to SQ2 dye, and thereby an ? value of 6.36% is achieved for the pertinent DSSC, which is much higher than those of the cells sensitized with individual dyes absorbing narrow wavelength of light, i.e., ? of 5.44% and 4.11% for the DSSC sensitized with JD1 (absorption wavelength from 400 to 550 nm) and SQ2 dye (absorption wavelength from 550 to 750 nm), respectively.

Lin, Lu-Yin; Yeh, Min-Hsin; Lee, Chuan-Pei; Chang, Jeffery; Baheti, Abhishek; Vittal, R.; Justin Thomas, K. R.; Ho, Kuo-Chuan

2014-02-01

40

High-performance liquid chromatographic separation of carminic acid, alpha- and beta-bixin, and alpha- and beta-norbixin, and the determination of carminic acid in foods.  

PubMed

During a study of natural food colours, a simple and reliable high-performance liquid chromatography system was developed for use with cochineal and annato. An isocratic mobile phase, consisting of methanol and 6% aqueous acetic acid, resolved bixin and norbixin, while a gradient system was used to separate carminic acid and the annato compounds. The carminic acid contents of cochineal extract, carmine and carmine hydrosoluble were determined using an isocratic mobile phase (40:60, v/v). The detection limit for carminic acid in the various products was approximately 100 ng/g. Carminic acid was determined quantitatively in fruit beverages, yogurt and candies. It was demonstrated that, because of decomposition, carminic acid was not suitable for use in candies when manufacturing temperatures above 100 degrees C were required. Most membrane filters are not suitable for use with cochineal solutions, but a cellulose membrane filter did not adsorb carminic acid and was used successfully to remove impurities from water-based cochineal products and food extracts containing carminic acid. PMID:8653204

Lancaster, F E; Lawrence, J F

1996-05-01

41

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

ERIC Educational Resources Information Center

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

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

2007-01-01

42

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

Microsoft Academic Search

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

L. Reijnders

2010-01-01

43

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

NASA Astrophysics Data System (ADS)

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

Pramodini, S.; Poornesh, P.

2014-11-01

44

Library of UV-Vis-NIR reflectance spectra of modern organic dyes from historic pattern-card coloured papers  

NASA Astrophysics Data System (ADS)

An accurate characterisation of the organic dyes used in artworks, especially those made of paper, is an important factor in designing safe conservation treatments. In the case of synthetic organic dyes used in modern works of art, for example, one frequently encountered difficulty is that some of these dyes are not still commercially available. Recognizing this problem, the authors of this paper present the results of an analysis of UV-Vis-NIR fibre optic reflectance spectra of 82 samples of dyed paper prepared with 41 dyes. The samples come from a historic book, The Dyeing of Paper in the Pulp, which was published by Interessen-Gemeinschaft (I.G.) Farbenindustrie in 1925. The dyes used in the paper pulp belong to the azo compounds, acridine, anthraquinone, azine, diphenylmethane, indigoid, methine, nitro, quinoline, thiazine, triphenylmethane, sulphur and xanthene classes.

Montagner, Cristina; Bacci, Mauro; Bracci, Susanna; Freeman, Rachel; Picollo, Marcello

2011-09-01

45

Library of UV-Vis-NIR reflectance spectra of modern organic dyes from historic pattern-card coloured papers.  

PubMed

An accurate characterisation of the organic dyes used in artworks, especially those made of paper, is an important factor in designing safe conservation treatments. In the case of synthetic organic dyes used in modern works of art, for example, one frequently encountered difficulty is that some of these dyes are not still commercially available. Recognizing this problem, the authors of this paper present the results of an analysis of UV-Vis-NIR fibre optic reflectance spectra of 82 samples of dyed paper prepared with 41 dyes. The samples come from a historic book, The Dyeing of Paper in the Pulp, which was published by Interessen-Gemeinschaft (I.G.) Farbenindustrie in 1925. The dyes used in the paper pulp belong to the azo compounds, acridine, anthraquinone, azine, diphenylmethane, indigoid, methine, nitro, quinoline, thiazine, triphenylmethane, sulphur and xanthene classes. PMID:21715217

Montagner, Cristina; Bacci, Mauro; Bracci, Susanna; Freeman, Rachel; Picollo, Marcello

2011-09-01

46

Carbazole-dendrimer-based donor-?-acceptor type organic dyes for dye-sensitized solar cells: effect of the size of the carbazole dendritic donor.  

PubMed

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

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

2014-06-11

47

Organic dye penetration quantification into a dental composite resin cured by LED system using fluorescence spectroscopy  

NASA Astrophysics Data System (ADS)

A major characteristic of LEDs systems is the lower heat emission related with the kind of light generation and spectral emission band. Material temperature during photoactivation can promote different photocuring performance. Organic dye penetration could be a trace to identify the efficacy of photocured composite resin. A new method using fluorescent spectroscopy through digital image evaluation was developed in this study. In order to understand if there is a real influence of material temperature during the photoactivation procedure of a dental restorative material, a hybrid composite resin (Z250, 3M-Espe, USA) and 3 light sources, halogen lamp (510 mW/cm2) and two LED systems 470+/-10nm (345 and 1000 mW/cm2) under different temperatures and intensities were used. One thousand and five hundred samples under different associations between light sources and temperatures (0, 25, 50, 75 and 100 °C were tested and immediately kept in 6G rodamin dye solution. Dye penetration was evaluated through fluorescent spectroscopy recorded by digital image data. Pixels in gray scale showed the percentage penetration of organic dye into the composite resin mass. Time and temperature were statistically significant (p<0.05) through the ANOVA statistical test. The lowest penetration value was with 60 seconds and 25 °C. Time and temperature are important factors to promote a homogeneous structure polymerized composite resin more than the light source type, halogen or LEDs system.

Lizarelli, Rosane de Fátima Zanirato; Silva, Maciel E., Jr.; Lins, Emery C. C. C.; Costa, Mardoqueu M.; Pelino, José Eduardo P.; Bagnato, Vanderlei S.

2007-02-01

48

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

PubMed

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

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

2012-12-14

49

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

PubMed

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

Buvaneswari, Natesan; Kannan, Chellapandian

2011-05-15

50

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)

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

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

2014-02-01

51

Adsorption of basic dyes in single and mixture systems on granular inorganic–organic pillared clays  

Microsoft Academic Search

The adsorption of two basic dyes, CI Basic Yellow 28 and CI Basic Green 4, was studied in single and binary solute systems using two classes of inorganic–organic pillared clay granules as sorbents (300–400 µm and 700–800 µm). These were prepared by high?shear wet granulation from an Al cetyltrimethylammonium bromide intercalated clay powder (particle diameter < 50 µm). Adsorption rate

Benamar Cheknane; Michel Baudu; Omar Bouras

2010-01-01

52

Degradation of Safranine T dye-based photo electrochemical organic photovoltaic devices  

Microsoft Academic Search

In this work, we studied the degradation of different photovoltaic parameters of Safranine T (ST) dye-doped organic photo\\u000a electrochemical cell (PEC). Different photovoltaic parameters were measured for as-prepared device. The same measurement was\\u000a repeated with time at 24-h regular interval for five successive days. During the measurement, the devices were unencapsulated\\u000a and kept in an open environment. The photovoltaic parameters

S. Maity; A. Haldar; N. B. Manik

2009-01-01

53

Green decomposition of organic dyes using octahedral molecular sieve manganese oxide catalysts.  

PubMed

The catalytic degradation of organic dye (methylene blue, MB) has been studied using green oxidation methods (tertiary-butyl hydrogen peroxide, TBHP, as the oxidant with several doped mixed-valent and regular manganese oxide catalysts in water) at room and higher temperatures. These catalysts belong to a class of porous manganese oxides known as octahedral molecular sieves (OMS). The most active catalysts were those of Mo(6+)- and V(5+)-doped OMS. Rates of reaction were found to be first-order with respect to the dye. TBHP has been found to enhance the MB decomposition, whereas H(2)O(2) does not. Reactions were studied at pH 3-11. The optimum pH for these reactions was pH 3. Dye-decomposing activity was proportional to the amount of catalyst used, and a significant increase in catalytic activity was observed with increasing temperature. X-ray diffraction (XRD), energy dispersive spectroscopy (EDX), and thermogravimetric analysis (TGA) studies showed that no changes in the catalyst structure occurred after the dye-degradation reaction. The products as analyzed by electrospray ionization mass spectrometry (ESI-MS) showed that MB was successively decomposed through different intermediate species. PMID:19178167

Sriskandakumar, Thamayanthy; Opembe, Naftali; Chen, Chun-Hu; Morey, Aimee; King'ondu, Cecil; Suib, Steven L

2009-02-26

54

Tailor-made hole-conducting coadsorbents for highly efficient organic dye-sensitized solar cells.  

PubMed

The Y-shaped, low molecular mass, hole-conductor (HC), acidic coadsorbents 4-{3,7-bis[4-(2-ethylhexyloxy)phenyl]-10H-phenothiazin-10-yl}benzoic acid (PTZ1) and 4-{3,7-bis[4-(2-ethylhexyloxy)phenyl]-10H-phenothiazin-10-yl}biphenyl-4-carboxylic acid (PTZ2) were developed. Owing to their tuned and negative-shifted HOMO levels (vs. NHE), they were used as HC coadsorbents in dye-sensitized solar cells (DSSCs) to improve cell performance through desired cascade-type hole-transfer processes. Their detailed functions as HC coadsorbents in DSSCs were investigated to obtain evidence for the desired cascade-type hole-transfer processes. They have multiple functions, such as preventing ?-? stacking of dye molecules, harvesting light of shorter wavelengths, and faster dye regeneration. By using PTZ2 as the tailor-made HC coadsorbent on the TiO2 surface with the organic dye NKX2677, an extremely high conversion efficiency of 8.95?% was achieved under 100?mW?cm(-2) AM 1.5G simulated light (short-circuit current JSC =16.56?mA?cm(-2) , open-circuit voltage VOC =740?mV, and fill factor of 73?%). Moreover, JSC was increased by 13?%, VOC by 27?% and power-conversion efficiency by 49?% in comparison to an NKX2677-based DSSC without an HC coadsorbent. This is due to the HC coadsorbent having a HOMO energy level well matched to that of the NKX-2677 dye to induce the desired cascade-type hole-transfer processes, which are associated with a slower charge recombination, fast dye regeneration, effective screening of liquid electrolytes, and an induced negative shift of the quasi-Fermi level of the electrode. Thus, this new class of Y-shaped, low molecular weight, organic, HC coadsorbents based on phenothiazine carboxylic acid derivatives hold promise for highly efficient organic DSSCs. PMID:24115151

Choi, In Taek; Ju, Myung Jong; Song, Sang Hyun; Kim, Sang Gyun; Cho, Dae Won; Im, Chan; Kim, Hwan Kyu

2013-11-11

55

Organic nanofibers from squarylium dyes: local morphology, optical, and electrical properties  

NASA Astrophysics Data System (ADS)

Environmentally stable, non-toxic squarylium dyes with strong absorption maxima in the red and near infrared spectral region are known for almost fifty years. Despite the fact that their optoelectronic properties distinguish them as promising materials for organics based photovoltaic cells, they have regained attention only very recently. For their application in heterojunction solar cells knowledge of their nanoscopic morphology as well as nanoscopic electrical properties is paramount. In this paper thin films from two different squarylium dyes, from squarylium (SQ) and from hydroxy-squarylium (SQOH) are investigated. The thin films are either solution casted or vacuum sublimed onto substrates such as muscovite mica, which are known to promote self-assembly into oriented, crystalline nanostructures such as nanofibers. Local characterization is performed via (polarized) optical microscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and Kelvin probe force microscopy (KPFM).

Balzer, Frank; Schiek, Manuela; Osadnik, Andreas; Lützen, Arne; Rubahn, Horst-Günter

2012-02-01

56

Efficient Organic Sensitizers with Pyridine-N-oxide as an Anchor Group for Dye-Sensitized Solar Cells.  

PubMed

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

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

2014-09-01

57

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

PubMed Central

Intradermal injections of indigo carmine for sentinel node mapping are considered safe and no report of an adverse reaction has been published. The authors described two cases of profound hypotension in women that underwent breast-conserving surgery after an intradermal injection of indigo carmine into the periareolar area for sentinel node mapping. PMID:23593094

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

2013-01-01

58

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

PubMed

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

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

2014-10-01

59

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

PubMed

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

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

60

Adsorption of basic dyes in single and mixture systems on granular inorganic-organic pillared clays.  

PubMed

The adsorption of two basic dyes, CI Basic Yellow 28 and CI Basic Green 4, was studied in single and binary solute systems using two classes of inorganic-organic pillared clay granules as sorbents (300-400 microm and 700-800 microm). These were prepared by high-shear wet granulation from an Al cetyltrimethylammonium bromide intercalated clay powder (particle diameter < 50 microm). Adsorption rate data indicate that BY 28 adsorbs more rapidly than BG 4 and a pseudo-first-order model was found to fit the kinetic curves, with regression coefficients above 0.98. Adsorption isotherms in single solute systems at pH 3 and pH6 were respectively analysed according to the Langmuir and Freundlich models using non-linear regression. Best fits were obtained with the Langmuir model. In binary dye systems the adsorption at three molar ratios (1:9, 1:1 and 9:1) demonstrated that the adsorption of BG 4 was greater than that of BY 28 on all the sorbents studied; this was in agreement with the results obtained for single solute systems. Increasing the granule size decreased dye adsorption, an effect in accordance with the Sheindorf-Rebuhn-Sheintuch model. PMID:20586243

Cheknane, Benamar; Baudu, Michel; Basly, Jean-Philippe; Bouras, Omar

2010-06-01

61

Degradation of organic dyes via bismuth silver oxide initiated direct oxidation coupled with sodium bismuthate based visible light photocatalysis.  

PubMed

Organic dye degradation was achieved via direct oxidation by bismuth silver oxide coupled with visible light photocatalysis by sodium bismuthate. Crystal violet dye decomposition by each reagent proceeded via two distinct pathways, each involving different active oxygen species. A comparison of each treatment method alone and in combination demonstrated that using the combined methods in sequence achieved a higher degree of degradation, and especially mineralization, than that obtained using either method alone. In the combined process direct oxidation acts as a pretreatment to rapidly bleach the dye solution which substantially facilitates subsequent visible light photocatalytic processes. The integrated sequential direct oxidation and visible light photocatalysis are complementary manifesting a > 100% increase in TOC removal, compared to either isolated method. The combined process is proposed as a novel and effective technology based on one primary material, sodium bismuthate, for treating wastewaters contaminated by high concentrations of organic dyes. PMID:22616904

Yu, Kai; Yang, Shaogui; Liu, Cun; Chen, Hongzhe; Li, Hui; Sun, Cheng; Boyd, Stephen A

2012-07-01

62

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

PubMed

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

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

2011-07-01

63

Determining the appropriate exchange-correlation functional for time-dependent density functional theory studies of charge-transfer excitations in organic dyes  

NASA Astrophysics Data System (ADS)

UV-Vis spectra are calculated using time-dependent density functional theory for several organic dyes - 4-(N, N-dimethylamino) benzonitrile, alizarin, squaraine, polyene-linker dyes, oligothiophene-containing coumarin dyes (NKX series) and triphenylamine-donor dyes. Most of these dyes (except, for the first two) or their derivatives are considered to be promising organic dyes for dye-sensitized solar cells. An accurate description of the photophysics of such dyes is imperative for understanding and creating better dyes. To this end, we studied the dyes within several approximations to the exchange-correlation functional. The chosen functionals - PBE, M06L, B3LYP, M06, CAM-B3LYP, and wB97 - represent the various classes of approximations that are currently being used to study material properties. From amongst the six approximations studied here, CAM-B3LYP outperformed the others in its description of charge-transfer excitations in most (though, not all) of the dyes. This study shows why it is difficult to choose a particular functional a priori, especially when starting out with a new dye for solar cell application. A possible way to judge the fitness of an approximation is used in this work and it is shown to provide a good quantitative guideline for subsequent research in this field.

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

2012-06-01

64

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

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

65

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

PubMed

Natural organic coagulants (NOCs) such as chitosan and Moringa oleifera seeds have been extensively characterized for potential application in water treatment as an alternative to metal-based coagulants. However, the action of both chitosan and M. oleifera seeds is mainly restricted to anionic organic pollutants because of their cationic functional groups affording poor cationic pollutant coagulation by electrostatic repulsion. In this study, we employed ethanolic grape seed extract (GSE) and grape seed-derived polyphenols such as tannic acid and catechin in an effort to find novel NOCs showing stable anionic forms for removal of cationic organic pollutants. The target substances tested were malachite green (MG) and crystal violet (CV), both mutagenic cationic dyes. Polyphenol treatment induced fast decolorization followed by gradual floc formation concomitant with red or blue shifts in maximum absorbance wavelengths of the cationic dyes. Liquid chromatography analysis of flocs formed by polyphenols directly showed that initial supramolecular complexes attributed mainly to electrostatic attraction between polyphenol hydroxyphenyl groups and cationic dyes further progressed into stronger aggregates, leading to precipitation of dye-polyphenol complexes. Consistent with the results obtained using catechin and tannic acid, use of GSE also resulted in effective decolorization and coagulation of soluble MG and CV in aqueous solutions. Screening of several organic GSE components for NOC activity strongly suggested that natural polyphenols are the main organic ingredients causing MG and CV removal via gradual floc formation. The treatment by natural polyphenols and GSE decreased toxicity of MG- or CV-contaminated water. PMID:19786292

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

2009-11-01

66

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

NASA Astrophysics Data System (ADS)

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

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

2013-10-01

67

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

PubMed

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

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

2013-01-01

68

Range separated hybrid density functional study of organic dye sensitizers on anatase TiO$_2$ nanowires  

E-print Network

The adsorption of organic molecules coumarin and the donor-$\\pi$-acceptor type tetrahydroquinoline (C2-1) on anatase (101) and (001) nanowires have been investigated using screened Coulomb hybrid density functional theory calculations. While coumarin forms single bond with the nanowire surface, C2-1 additionally exhibits bidentate mode giving rise to much stronger adsorption energies. Nonlinear solvation effects on the binding characteristics of the dye chromophores on the nanowire facets have also been examined. These two dye sensitizers show different electronic charge distributions for the highest occupied and the lowest unoccupied molecular states. We studied the electronic structures in terms of the positions of the band edges and adsorbate related band gap states and their effect on the absorption spectra of the dye-nanowire combined systems. These findings were interpreted and discussed from the view point of better light harvesting and charge separation as well as in relation to more efficient charge ...

Unal, Hatice; Gulseren, Oguz; Ellialtioglu, Sinasi; Mete, Ersen

2014-01-01

69

Application of solution processable squaraine dyes as electron donors for organic bulk-heterojunction solar cells.  

PubMed

New low bandgap small molecules based on a squaraine (SQ) chromophore, bis[4-(2,6-di-tert-butyl)vinylpyrylium]squaraine (TBU-SQ), bis[2,6-di-tert-butyl-4-(prop-1-en-2-yl)pyrylium]squaraine (MeTBU-SQ) and bis[4-(but-1-en-2-yl)-2,6-di-tert-butylpyrylium]squaraine (EtTBU-SQ), were synthesized and used as electron donors along with PC70BM for their application in solution processed organic bulk-heterojunction (OBHJ) solar cell (SC). The long wavelength of these SQ dyes are located in between 650-750 nm in thin films and the optical bandgaps are about 1.64, 1.52 and 1.48 eV, respectively. The electrochemical properties of these SQ dyes indicate that they are well suited for the fabrication of OBHJSCs as electron donors along with fullerene derivatives as electron acceptors. The OBHJ photovoltaic (PV) devices fabricated with the blend of TBU-SQ:PC70BM, MeTBU-SQ:PC70BM and EtTBU-SQ:PC70BM cast from chloroform (CF) solvent exhibited a power conversion efficiency (PCE) of 1.71%, 2.15%, and 1.89%, respectively. The PCE of the OBHJSCs based on MeTBU-SQ:PC70BM blends cast from DIO-THF (DIO = 1,8-diiodooctane) additive solvent and cast from DIO-THF with subsequent thermal annealing have been further improved up to 2.73% and 3.14%, respectively. This enhancement in the PCE is attributed to the improvement in the crystalline nature of the blend and more balanced charge transport resulting from the higher hole mobility. All these results have been supported by the quantum chemical calculations. PMID:23788052

Rao, B Ananda; Yesudas, K; Kumar, G Siva; Bhanuprakash, K; Rao, V Jayathirtha; Sharma, G D; Singh, S P

2013-09-01

70

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

NASA Astrophysics Data System (ADS)

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

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

2013-05-01

71

Sonochemical degradation of chlorinated organic compounds, phenolic compounds and organic dyes – A review  

Microsoft Academic Search

Sonochemical processes have been widely used in chemistry and chemical engineering field. Recently, these processes have found new applications in the environmental field, because of advantages in terms of operational simplicity, secondary pollutant formation and safety. Several studies have reported on sonochemical degradation of organic compounds that are toxic in nature. The objective of this review was to identify and

Pankaj Chowdhury; T. Viraraghavan

2009-01-01

72

Multifunctional organized mesoporous tin oxide films templated by graft copolymers for dye-sensitized solar cells.  

PubMed

The synthesis of organized mesoporous SnO2 films with high porosity, larger pores, and good interconnectivity, obtained by sol-gel templating with an amphiphilic graft copolymer, poly(vinyl chloride)-graft-poly(oxyethylene methacrylate), is reported. An improved performance of dye-sensitized solar cells (DSSCs) is demonstrated by the introduction of a 400 nm thick organized mesoporous SnO2 interfacial (om-SnO2 IF) layer between nanocrystalline TiO2 (nc-TiO2 ) and a fluorine-doped tin oxide substrate. To elucidate the improved efficiency, the structural, optical, and electrochemical properties of the devices were characterized by SEM, UV/Vis spectroscopy, noncontact 3D surface profilometry, intensity-modulated photocurrent/voltage spectroscopy, incident photon-to-electron conversion efficiency, and electrochemical impedance spectroscopy measurements. The energy-conversion efficiency of the solid polymerized ionic liquid based DSSC fabricated with the om-SnO2 IF/nc-TiO2 photoanode reached 5.9% at 100 mW cm(-2) ; this is higher than those of neat nc-TiO2 (3.5%) and organized mesoporous TiO2 interfacial/nc-TiO2 layer (5.4%) photoanodes. The improved efficiency is attributed to the antireflective property, cascadal energy band gap, good interconnectivity, and high electrical conductivity of the om-SnO2 IF layer, which results in enhanced light harvesting, increased electron transport, reduced charge recombination, and decreased interfacial/internal resistance. PMID:24678065

Park, Jung Tae; Ahn, Sung Hoon; Roh, Dong Kyu; Lee, Chang Soo; Kim, Jong Hak

2014-07-01

73

Preparation of dye waste-barium sulfate hybrid adsorbent and application in organic wastewater treatment.  

PubMed

A new hybrid material was developed by the template-free hybridization of weak acidic pink red B (APRB, C.I. 18073) with BaSO(4). The composition and structure of the material were determined and characterized. In contrast to conventional sorbents, the hybrid material has a specific surface area of 0.89 m(2)/g, but it contains lots of negative charges and lipophilic groups as the basis of specific adsorption. The efficient removal of cationic dyes and persistent organic pollutants (POPs) indicates that it has an improved adsorption capacity and selectivity with a short removal time less than 2 min; while the hybrid sorbents fit the Langmuir isotherm model, and follow the octanol-water partition law. Instead of using APRB reagent, an APRB-producing wastewater was reused to prepare the cost-effective sorbent, and the equilibrium adsorption capacities of which reached 222 and 160 mg/g for EV and BPR, respectively. The sorbents was then used to treat three wastewater samples with satisfactory results of over 97% decolonization and 88% COD-decreasing. In addition, the hybrid sorbent was regenerated from sludge over five cycles, and its adsorption capacity was not appreciably changed. This work has developed a simple and eco-friendly method for synthesizing a practical and efficient sorbent. PMID:19850409

Hu, Zhang-Jun; Xiao, Yan; Zhao, Dan-Hua; Shen, Yu-Lin; Gao, Hong-Wen

2010-03-15

74

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

PubMed

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

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

2014-06-21

75

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

SciTech Connect

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

Parkinson, Bruce

2010-06-04

76

Aggregation control of organic sensitizers for panchromatic dye co-sensitized solar cells  

NASA Astrophysics Data System (ADS)

The photovoltaic properties of dye co-sensitized solar cells were compared with those of mono-sensitized devices. Co-sensitized TiO2 photo-electrodes were prepared from a phenothiazine chromophore for the RED dye and a squaraine chromophore for the BLUE dye to achieve panchromatic light absorption in dye co-sensitized solar cells (DSSCs). Co-sensitization on the TiO2 photo-electrode could reduce the aggregation of the BLUE dye adsorbed on the TiO2 surface, which led to an enhancement of the short circuit current (Jsc) of the co-sensitized solar cells. The dye co-sensitized solar cells with the RED and BLUE dyes optimized according to the dipping time showed an increase in the photon-to-current efficiency compared to that of the solar cell with a mono-sensitized photo-electrode. The photovoltaic and aggregation properties of the DSSCs were examined by measuring the current-voltage curve, incident photon-to-current efficiency, and electrochemical impedance spectra.

Lee, Chi Hwan; Kim, Sang A.; Jung, Mi Ran; Ahn, Kwang-Soon; Han, Yoon Soo; Kim, Jae Hong

2014-08-01

77

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

PubMed

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

Cho, Bum Hwi; Ko, Weon Bae

2013-11-01

78

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

Federal Register 2010, 2011, 2012, 2013

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

2010-12-29

79

Supported cobalt oxide on MgO: Highly efficient catalysts for degradation of organic dyes in dilute solutions  

Microsoft Academic Search

Cobalt oxide catalysts immobilized on various oxides (MgO, ZnO, Al2O3, ZrO2, P25, SBA-15) were prepared for degradation of organic dyes in dilute solutions via a sulfate radical approach. Their efficiency in activation of peroxymonosulfate (PMS) was investigated for the degradation of methylene blue (MB). Among the catalysts employed, the Co\\/MgO catalyst was found the most active. The complete degradation of

Wei Zhang; Hui Lin Tay; Sze Sheng Lim; Yongsheng Wang; Ziyi Zhong; Rong Xu

2010-01-01

80

High-efficiency orange and tandem white organic light-emitting diodes using phosphorescent dyes with horizontally oriented emitting dipoles.  

PubMed

Tandem white organic light-emitting diodes (WOLEDs) using horizontally oriented phosphorescent dyes in an exciplex-forming co-host are presented, along with an orange OLED. A high external quantum efficiency of 32% is achieved for the orange OLED at 1000 cd m(-2) and the tandem WOLEDs exhibit a high maximum EQE of 54.3% (PE of 63 lm W(-1)). PMID:24923483

Lee, Sunghun; Shin, Hyun; Kim, Jang-Joo

2014-09-01

81

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

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

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

2014-01-01

82

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

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

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

2014-01-01

83

Modulating triphenylamine-based organic dyes for their potential application in dye-sensitized solar cells: a first principle theoretical study.  

PubMed

By using computational methodologies based on time dependent density functional theory (TDDFT) we study the opto-electronic properties of three types of triphenylamine (TPA)-based dyes, namely TPA-TBT-1, TPA-DBT-1, and TPA-BT-1, and these are proposed as potential candidates for photovoltaic applications. Energy band modulation has been performed by functionalizing these dyes with different electron donating and electron withdrawing groups. Photoelectron spectra and photovoltaic properties of the dyes have been investigated by a combination of DFT and TDDFT approaches. Based on the optimized molecular geometry, relative position of the frontier energy levels, and the absorption maximum of the dyes we propose some dyes offering good photovoltaic performance. At the same time, these results provide a direction for optimizing the composition of dye-metal surface nanodevices for fabricating dye-sensitized solar cells (DSSCs). PMID:25335462

Nath Ghosh, Narendra; Chakraborty, Arnab; Pal, Sougata; Pramanik, Anup; Sarkar, Pranab

2014-12-14

84

Novel magnetic Fe3O4@C nanoparticles as adsorbents for removal of organic dyes from aqueous solution.  

PubMed

The magnetic Fe(3)O(4)/C core-shell nanoparticles have been synthesized by a simple strategy and used as adsorbents for removal of organic dyes from aqueous solution. The resulting products are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectra and Fourier transform infrared spectra (FTIR). Adsorption performances of the nanomaterial adsorbents are tested with removal of methylene blue (MB) and cresol red (CR) from aqueous solution. The effects of solution pH value, adsorption time and capacity of the nanocomposites have been fully investigated. The results reveal that the nanospheres can be easily manipulated by an external magnetic field with high separation efficiency. In addition, the process is clean and safe for purifying water pollution. The prepared Fe(3)O(4)/C complex nanomaterials could thus be used as promising adsorbents for the remove organic dyes, especially, cationic dye, from polluted water. PMID:21813238

Zhang, Zhengyong; Kong, Jilie

2011-10-15

85

Femtosecond spectroscopic study of carminic acid-DNA interactions Radu Comanicia  

E-print Network

for the formation of intercalation complexes between the carminic acid and the DNA. The intercalative binding intercalating of the chromophore between the CG base pairs of DNA. The intercalation process is followed by conformational relaxation of the anthracycline-DNA complex [3,4]. Formation of intercalation complexes has been

Paris-Sud XI, Université de

86

A Survey on Whiting Fillet Blocks CARMINE GORGA and KEVIN J. ALLEN  

E-print Network

Middle Street, Gloucester, MA 01930. Kevin J. Allen is Chief, Marketing Services Branch, Fisheries is in the northeast re- gion. Questionnaires were independently completed and were returned to the Marketing Services of whiting fillet blocks by respondents. Carmine Gorga is an Economic Consultant with Polis-tics, [nc., 87

87

Assessing the fitness of various exchange-correlation functionals for TD-DFT studies of charge-transfer excitations in organic dyes  

NASA Astrophysics Data System (ADS)

Dye Sensitized Solar Cells (DSSCs) are a possible alternative to the more expensive silicon-based cells. Theoretical research in this field has highlighted some of the issues with time-dependent density functional theory (TD-DFT) that is widely used to study electronic excitations of matter. The situation is complicated by the fact that several classes of approximations to the exchange correlation functional can be employed, however, not one of these strictly outperforms the others in its description of charge-transfer excitations. In this work, UV-Vis spectra are calculated using TD-DFT for several organic dyes -- alizarin, squaraine, 4-(N, N-dimethylamino) benzonitrile, polyene-linker dyes and triphenylamine-donor dyes. We studied the dyes within three approximations (PBE, B3LYP and CAM-B3LYP) to the exchange-correlation functional. In the dyes considered here, a correlation exists between the functional performance and the spatial overlap of the states involved in the excitations. This overlap can be quantified to provide a good guideline for choosing the right functional when studying intramolecular charge transfer in dyes. It will be an invaluable tool when studying these molecules within more challenging systems, such as dye-titania complexes in DSSCs.

Dev, Pratibha; Agrawal, Saurabh; English, Niall

2012-02-01

88

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

PubMed Central

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

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

2014-01-01

89

Synthesis and Characterization of Organic Dyes with Various Electron-Accepting Substituents for p-Type Dye-Sensitized Solar Cells.  

PubMed

Four new donor-?-acceptor dyes differing in their acceptor group have been synthesized and employed as model systems to study the influence of the acceptor groups on the photophysical properties and in NiO-based p-type dye-sensitized solar cells. UV/Vis absorption spectra showed a broad range of absorption coverage with maxima between 331 and 653?nm. Redox potentials as well as HOMO and LUMO energies of the dyes were determined from cyclic voltammetry measurements and evaluated concerning their potential use as sensitizers in p-type dye-sensitized solar cells (p-DSCs). Quantum-chemical density functional theory calculations gave further insight into the frontier orbital distributions, which are relevant for the electronic processes in p-DSCs. In p-DSCs using an iodide/triiodide-based electrolyte, the polycyclic 9,10-dicyano-acenaphtho[1,2-b]quinoxaline (DCANQ) acceptor-containing dye gave the highest power conversion efficiency of 0.08?%, which is comparable to that obtained with the perylenemonoimide (PMI)-containing dye. Interestingly, devices containing the DCANQ-based dye achieve a higher VOC of 163?mV compared to 158?mV for the PMI-containing dye. The result was further confirmed by impedance spectroscopic analysis showing higher recombination resistance and thus a lower recombination rate for devices containing the DCANQ dye than for PMI dye-based devices. However, the use of the strong electron-accepting tricyanofurane (TCF) group played a negative role in the device performance, yielding an efficiency of only 0.01?% due to a low-lying LUMO energy level, thus resulting in an insufficient driving force for efficient dye regeneration. The results demonstrate that a careful molecular design with a proper choice of the acceptor unit is essential for development of sensitizers for p-DSCs. PMID:25234556

Weidelener, Martin; Powar, Satvasheel; Kast, Hannelore; Yu, Ze; Boix, Pablo P; Li, Chen; Müllen, Klaus; Geiger, Thomas; Kuster, Simon; Nüesch, Frank; Bach, Udo; Mishra, Amaresh; Bäuerle, Peter

2014-11-01

90

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

Microsoft Academic Search

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

Patrik R. Callis

91

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

PubMed Central

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

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

2014-01-01

92

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

PubMed

The photocatalytic degradation of five anionic, eight cationic and three solvent dyes using combustion-synthesized nano-TiO(2) (CS TiO(2)) and commercial Degussa P-25 TiO(2) (DP-25) were evaluated to determine the effect of the functional group in the dye. The degradation of the dyes was quantified using the initial rate of decolorization and mineralization. The decolorization of the anionic dyes with CS TiO(2) followed the order: indigo carmine > eosin Y > amido black 10B > alizarin cyanine green > orange G. The decolorization of the cationic dyes with DP-25 followed the order: malachite green > pyronin Y > rhodamine 6G > azure B > nile blue sulfate > auramine O approximately = acriflavine approximately = safranin O. CS TiO(2) showed higher rates of decolorization and mineralization for all the anionic dyes compared to DP-25, while DP-25 was better in terms of decolorization for most of the cationic dyes. The solvent dyes exhibited adsorption dependent decolorization. The order of decolorization and mineralization of the anionic and cationic dyes (a) with CS TiO(2) and DP-25 was different and correlated with the surface properties of these catalysts (b) were rationalized with the molecular structure of the dye and the degradation pathway of the dye. PMID:20018445

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

2010-04-15

93

An advanced Ag-based photocatalyst Ag2Ta4O11 with outstanding activity, durability and universality for removing organic dyes.  

PubMed

Constructing Ag-based photocatalysts by the incorporation of Ag(+) ions into metal/nonmetal oxides for removing organic pollutants is a recently developed strategy, but overcoming their own photocorrosion is still a tremendous challenge. In this work, an advanced Ag-based photocatalyst Ag2Ta4O11 is obtained by this strategy, which exhibits improved photocatalytic activity compared with Ta2O5 and the universality for degrading several organic dyes. Importantly, the Ag2Ta4O11 photocatalyst has outstanding durability and reusability, which indicates that it has potential application prospects for organic wastewater treatment in the printing and dyeing industry. PMID:25277949

Dong, Hongjun; Sun, Jingxue; Chen, Gang; Li, Chunmei; Hu, Yidong; Lv, Chade

2014-11-21

94

An optical nanocavity incorporating a fluorescent organic dye having a high quality factor.  

PubMed

We have fabricated an L3 optical nanocavity operating at visible wavelengths that is coated with a thin-film of a fluorescent molecular-dye. The cavity was directly fabricated into a pre-etched, free-standing silicon-nitride (SiN) membrane and had a quality factor of Q = 2650. This relatively high Q-factor approaches the theoretical limit that can be expected from an L3 nanocavity using silicon nitride as a dielectric material and is achieved as a result of the solvent-free cavity-fabrication protocol that we have developed. We show that the fluorescence from a red-emitting fluorescent dye coated onto the cavity surface undergoes strong emission intensity enhancement at a series of discrete wavelengths corresponding to the cavity modes. Three dimensional finite difference time domain (FDTD) calculations are used to predict the mode structure of the cavities with excellent agreement demonstrated between theory and experiment. PMID:20499907

Adawi, Ali M; Murshidy, Mohamed M; Fry, Paul W; Lidzey, David G

2010-06-22

95

A comparative study of non-covalent encapsulation methods for organic dyes into silica nanoparticles  

PubMed Central

Numerous luminophores may be encapsulated into silica nanoparticles (< 100 nm) using the reverse microemulsion process. Nevertheless, the behaviour and effect of such luminescent molecules appear to have been much less studied and may possibly prevent the encapsulation process from occurring. Such nanospheres represent attractive nanoplatforms for the development of biotargeted biocompatible luminescent tracers. Physical and chemical properties of the encapsulated molecules may be affected by the nanomatrix. This study examines the synthesis of different types of dispersed silica nanoparticles, the ability of the selected luminophores towards incorporation into the silica matrix of those nanoobjects as well as the photophysical properties of the produced dye-doped silica nanoparticles. The nanoparticles present mean diameters between 40 and 60 nm as shown by TEM analysis. Mainly, the photophysical characteristics of the dyes are retained upon their encapsulation into the silica matrix, leading to fluorescent silica nanoparticles. This feature article surveys recent research progress on the fabrication strategies of these dye-doped silica nanoparticles. PMID:21711855

2011-01-01

96

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

NASA Astrophysics Data System (ADS)

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

Madrakian, Tayyebeh; Afkhami, Abbas; Ahmadi, Mazaher

2012-12-01

97

UV light induced photodegradation of organic dye by ZnO nanocatalysts  

SciTech Connect

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

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

2013-06-03

98

Electroactive organic dye incorporating dipeptides in the formation of self-assembled nanofibrous hydrogels.  

PubMed

In this study, we examined the self-assembly of four dipeptides conjugated with the electroactive dye naphthalenediimide (NDI). The presence of the NDI group at the N-terminus of Phe-Phe and Phe-Gly promoted the formation of one-dimensional (1-D) nanostructures and three-dimensional (3-D) colored hydrogels under both acidic and physiological conditions. The 1-D nanostructures of these gels were stabilized through intermolecular ?-? interactions of the conjugated systems and extended hydrogen bonding of the dipeptide units. PMID:25229206

Liu, Yu-Hao; Hsu, Shu-Min; Wu, Fang-Yi; Cheng, Hsun; Yeh, Mei-Yu; Lin, Hsin-Chieh

2014-10-15

99

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

PubMed

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

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

2014-04-28

100

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

PubMed Central

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.

2014-01-01

101

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

PubMed

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

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

2014-07-01

102

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

PubMed

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

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

2011-01-01

103

High-performance organic thin-film transistors of J-stacked squaraine dyes.  

PubMed

We have synthesized a series of dipolar squaraine dyes that contain dicyanovinyl groups as acceptor and benzannulated five-membered ring heterocycles with alkyl chains of varied length as donor moieties. Based on these squaraines, thin-film transistors (TFT) were fabricated by spin coating and solution shearing. Moreover, with one of these squaraine derivatives vacuum-deposited TFTs were prepared as well. Our detailed studies revealed that the transistor performance of the present series of squaraines is strongly dependent on their structural features as well as on the processing method of thin films. Thus, solution-sheared OTFTs of selenium squaraine bearing dodecyl substituents (denoted as Se-SQ-C12) performed best with a maximum hole mobility of 0.45 cm(2) V(-1) s(-1), which is by far the highest value yet reported for OTFTs based on squaraines. This value was even surpassed by vacuum-deposited thin films of n-butyl-substituted selenium squaraine Se-SQ-C4, the only sublimable compound in this series, exhibiting a record hole mobility of 1.3 cm(2) V(-1) s(-1). Furthermore, we have investigated the morphology of the thin films and the molecular packing of these squaraine dyes by optical spectroscopy, atomic force microscopy, and X-ray diffraction. These studies revealed a relationship between the molecular structure, packing motif, thin-film morphology, and transistor performance of the squaraine dyes. From the supramolecular point of view two packing features discovered in the single crystal structure of Se-SQ-C8 are of particular interest with regard to the structure-functionality relationship: The first is the slipped and antiparallel ?-stacking motif which ensures cancellation of the molecules' dipole moments and J-type absorption band formation in thin films. The second is the presence of CN···Se noncovalent bonds which show similarities to the more common halogen-bonding interactions and which interconnect the individual one-dimensional slipped ?-stacks, thus leading to two-dimensional percolation pathways along the source-drain direction. PMID:24432873

Gsänger, Marcel; Kirchner, Eva; Stolte, Matthias; Burschka, Christian; Stepanenko, Vladimir; Pflaum, Jens; Würthner, Frank

2014-02-12

104

A shortcut organic dye-based staining method for the detection of DNA both in agarose and polyacrylamide gel electrophoresis.  

PubMed

In this study, we describe a brief, sensitive and safe organic dye-based staining method for the visualization of DNA both in agarose and polyacrylamide gels by using Victoria Pure Blue BO (VPBBO). Down to 0.8-1.6 ng of ? DNA/HindIII markers in agarose gels and 0.4-0.8 ng of pUC18 DNA/Mspl markers in polyacrylamide gels can be successfully detected within 15 and 10 min by the new developed technique, respectively. Moreover, the mechanism of the VPBBO staining was investigated and further confirmed by electrospray ionization mass spectrometry (ESI-MS) and molecular docking. The results indicated that the interaction between VPBBO and DNA is mainly due to groove binding. PMID:23296513

Cong, Weitao; Chen, Mao; Zhu, Zhongxin; Liu, Zhiguo; Nan, Jia; Ye, Weijian; Ni, Maowei; Zhao, Ting; Jin, Litai

2013-02-21

105

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

NASA Astrophysics Data System (ADS)

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

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

1999-07-01

106

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

Microsoft Academic Search

Ultrashort pulses of duration 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)

V I Avdeeva; Boris I Shapiro; Aleksandr S Kuchyanov; A I Plekhanov; Yu L Solominskii; Alexei I Tolmachev

2003-01-01

107

SEPARATION OF HISTORICAL DYES USING CAPILLARY ELECTROPHORESIS WITH LASER-INDUCED FLUORESCENCE DETECTION  

Microsoft Academic Search

In this study, the separation properties of alizarin, purpurin, carmine and morin were explored using capillary electrophoresis (CE). A 30 cm capillary (10 µm i.d.) and an applied voltage of 16-20 kV was used to separate the dyes prior to post-column detection in a sheath flow cuvette using laser-induced fluorescence (LIF). Two lasers were used for excitation; a 488 nm argon ion laser and

Douglas M. Goltz; Shokoufeh Ahmadi; Ghodrattolah Absalan; Douglas B. Craig

2012-01-01

108

High-power and high-gain organic dye-doped polymer optical fiber amplifiers: novel techniques for preparation and spectral investigation  

Microsoft Academic Search

Rhodamine B (RB), Rhodamine 6G (R6G), Oxazine 4 perchlorate (O4PC), and 4-Dicyanomethylene-2-methyl-6-( p -dimethylaminostyryl -4H-pyran)-doped graded-index (GI) polymer optical fiber amplifiers (POFA s) were successfully prepared by novel techniques to prevent degradation of organic dyes and to enhance solubility of the dyes in methyl methacrylate and in poly(methyl methacrylate) (PMMA). High-power (620 W) and high-gain (33-dB, 2070 times) amplification was

Akihiro Tagaya; Shigehiro Teramoto; Eisuke Nihei; Keisuke Sasaki; Yasuhiro Koike

1997-01-01

109

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

PubMed

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

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

2014-02-12

110

Treatment of dyeing wastewater by TiO2/H2O2/UV process: experimental design approach for evaluating total organic carbon (TOC) removal efficiency.  

PubMed

Optimal operating conditions in order to treat dyeing wastewater were investigated by using the factorial design and responses surface methodology (RSM). The experiment was statistically designed and carried out according to a 22 full factorial design with four factorial points, three center points, and four axial points. Then, the linear and nonlinear regression was applied on the data by using SAS package software. The independent variables were TiO2 dosage, H2O2 concentration and total organic carbon (TOC) removal efficiency of dyeing wastewater was dependent variable. From the factorial design and responses surface methodology (RSM), maximum removal efficiency (85%) of dyeing wastewater was obtained at TiO2 dosage (1.82 gL(-1)), H2O2 concentration (980 mgL(-1)) for oxidation reaction (20 min). PMID:15717785

Lee, Seung-Mok; Kim, Young-Gyu; Cho, Il-Hyoung

2005-01-01

111

Recycling of agricultural solid waste, coir pith: Removal of anions, heavy metals, organics and dyes from water by adsorption onto ZnCl 2 activated coir pith carbon  

Microsoft Academic Search

The abundant lignocellulosic agricultural waste, coir pith is used to develop ZnCl2 activated carbon and applied to the removal of toxic anions, heavy metals, organic compounds and dyes from water. Sorption of inorganic anions such as nitrate, thiocyanate, selenite, chromium(VI), vanadium(V), sulfate, molybdate, phosphate and heavy metals such as nickel(II) and mercury(II) has been studied. Removal of organics such as

C. Namasivayam; D. Sangeetha

2006-01-01

112

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

PubMed Central

Carrier multiplication describes an interesting optical phenomenon in semiconductors whereby more than one electron-hole pair, or exciton, can be simultaneously generated upon absorption of a single high-energy photon. So far, it has been highly debated whether the carrier multiplication efficiency is enhanced in semiconductor nanocrystals as compared with their bulk counterpart. The controversy arises from the fact that the ultrafast optical methods currently used need to correctly account for the false contribution of charged excitons to the carrier multiplication signals. Here we show that this charged exciton issue can be resolved in an energy transfer system, where biexcitons generated in the donor nanocrystals are transferred to the acceptor dyes, leading to an enhanced fluorescence from the latter. With the biexciton Auger and energy transfer lifetime measurements, an average carrier multiplication efficiency of ~17.1% can be roughly estimated in CdSe nanocrystals when the excitation photon energy is ~2.46 times of their energy gap. PMID:23132020

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

2012-01-01

113

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

NSDL National Science Digital Library

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

Majerich, David M.; Schmuckler, Joseph S.

2008-03-01

114

A microporous anionic metal-organic framework for sensing luminescence of lanthanide(III) ions and selective absorption of dyes by ionic exchange.  

PubMed

Herein, a novel anionic framework with primitive centered cubic (pcu) topology, [(CH3 )2 NH2 ]4 [(Zn4 dttz6 )Zn3 ]?15?DMF?4.5?H2 O, (IFMC-2; H3 dttz=4,5-di(1H-tetrazol-5-yl)-2H-1,2,3-triazole) was solvothermally isolated. A new example of a tetranuclear zinc cluster {Zn4 dttz6 } served as a secondary building unit in IFMC-2. Furthermore, the metal cluster was connected by Zn(II) ions to give rise to a 3D open microporous structure. The lanthanide(III)-loaded metal-organic framework (MOF) materials Ln(3+) @IFMC-2, were successfully prepared by using ion-exchange experiments owing to the anionic framework of IFMC-2. Moreover, the emission spectra of the as-prepared Ln(3+) @IFMC-2 were investigated, and the results suggested that IFMC-2 could be utilized as a potential luminescent probe toward different Ln(3+) ions. Additionally, the absorption ability of IFMC-2 toward ionic dyes was also performed. Cationic dyes can be absorbed, but not neutral and anionic dyes, thus indicating that IFMC-2 exhibits selective absorption toward cationic dyes. Furthermore, the cationic dyes can be gradually released in the presence of NaCl. PMID:24677301

Qin, Jun-Sheng; Zhang, Shu-Ran; Du, Dong-Ying; Shen, Ping; Bao, Shao-Juan; Lan, Ya-Qian; Su, Zhong-Min

2014-05-01

115

A study of the effects of injection mode, on-capillary stacking and off-line concentration on the capillary electrophoresis limits of detection for four structural types of industrial dyes  

Microsoft Academic Search

The limits of detection of four structural types of industrial dyes — Malachite Green (MG), Indigo Carmine (IC), Cibacron Blue 3GA (CB) and Remazol Black B (RB) — by capillary zone electrophoresis (CZE) were investigated by both hydrodynamic and electrokinetic injection. The LODs obtained using a 30 s hydrodynamic injection were compared to those achieved using a 30 s +

Lorraine Farry; Darren A. Oxspring; W. Franklin Smyth; Roger Marchant

1997-01-01

116

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

PubMed

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

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

2013-08-01

117

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

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

118

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

PubMed Central

Stable white-emitting down-converted LEDs are straightforwardly prepared by bulk polymerization of an organic dye doped polymethyl-methacrylate (PMMA) shell directly on top of a highly efficient commercial blue-emitting InGaN LED. Our optimized polymerization procedure allows for extending the form factor of achievable luminescence converter (LUCO) material beyond the conventional thin film form and to directly produce devices with light bulb design. The selected organic dyes, the blue-emitting Coumarin 30 and a red-emitting diketopyrrolopyrrole derivative, exhibit high compatibility with the free radical polymerization reaction of the PMMA matrix and ensure high stability of the final hybrid device. The control of both the thickness of the PMMA shell and the concentration of the dopant dyes allow for fine tuning of the emission color of the LUCO LED and to obtain white light with CIE chromatic coordinates x = 0.32 and y = 0.33, with rendering index as high as 80. This simple and versatile procedure is not dye-exclusive and is therefore extendable to other molecular systems for color-tunable efficient solid-state lighting sources. PMID:24638041

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

2014-01-01

119

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

ERIC Educational Resources Information Center

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.…

Marks, Patrick; Levine, Mindy

2012-01-01

120

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

Microsoft Academic Search

Growing public awareness on the potential risk to humans of toxic chemicals in the environment has generated demand for new and improved methods for toxicity assessment and removal, rational means for health risk estimation. With the aim of controlling nanoscale adsorbents for functionality in molecular sieving of organic pollutants, we fabricated cubic Im3m mesocages with uniform entrance and large cavity

Sherif A. El-Safty; Ahmed Shahat

121

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

PubMed

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

Kuno, Nayumi; Mizutani, Takaharu

2005-08-27

122

N-Doped graphene nanoplatelets as superior metal-free counter electrodes for organic dye-sensitized solar cells.  

PubMed

Highly efficient counter electrodes (CEs) for dye-sensitized solar cells (DSSCs) were developed using thin films of scalable and high-quality, nitrogen-doped graphene nanoplatelets (NGnP), which was synthesized by a simple two-step reaction sequence. The resultant NGnP was deposited on fluorine-doped SnO2 (FTO)/glass substrates by using electrospray (e-spray) coating, and their electrocatalytic activities were systematically evaluated for Co(bpy)3(3+/2+) redox couple in DSSCs with an organic sensitizer. The e-sprayed NGnP thin films exhibited outstanding performances as CEs for DSSCs. The optimized NGnP electrode showed better electrochemical stability under prolonged cycling potential, and its Rct at the interface of the CE/electrolyte decreased down to 1.73 ? cm(2), a value much lower than that of the Pt electrode (3.15 ? cm(2)). The DSSC with the optimized NGnP-CE had a higher fill factor (FF, 74.2%) and a cell efficiency (9.05%), whereas those of the DSSC using Pt-CE were only 70.6% and 8.43%, respectively. To the best of our knowledge, the extraordinarily better current-voltage characteristics of the DSSC-NGnP outperforming the DSSC-Pt for the Co(bpy)3(3+/2+) redox couple (in paticular, FF and short circuit current, Jsc) is highlighted for the first time. PMID:23656316

Ju, Myung Jong; Kim, Jae Cheon; Choi, Hyun-Jung; Choi, In Taek; Kim, Sang Gyun; Lim, Kimin; Ko, Jaejung; Lee, Jae-Joon; Jeon, In-Yup; Baek, Jong-Beom; Kim, Hwan Kyu

2013-06-25

123

Phosphorescent dye-based supramolecules for high-efficiency organic light-emitting diodes.  

PubMed

Organic light-emitting diodes (OLEDs) are among the most promising organic semiconductor devices. The recently reported external quantum efficiencies (EQEs) of 29-30% for green and blue phosphorescent OLEDs are considered to be near the limit for isotropically oriented iridium complexes. The preferred orientation of transition dipole moments has not been thoroughly considered for phosphorescent OLEDs because of the lack of an apparent driving force for a molecular arrangement in all but a few cases, even though horizontally oriented transition dipoles can result in efficiencies of over 30%. Here we use quantum chemical calculations to show that the preferred orientation of the transition dipole moments of heteroleptic iridium complexes (HICs) in OLEDs originates from the preferred direction of the HIC triplet transition dipole moments and the strong supramolecular arrangement within the co-host environment. We also demonstrate an unprecedentedly high EQE of 35.6% when using HICs with phosphorescent transition dipole moments oriented in the horizontal direction. PMID:25204981

Kim, Kwon-Hyeon; Lee, Sunghun; Moon, Chang-Ki; Kim, Sei-Yong; Park, Young-Seo; Lee, Jeong-Hwan; Woo Lee, Jin; Huh, June; You, Youngmin; Kim, Jang-Joo

2014-01-01

124

Phosphorescent dye-based supramolecules for high-efficiency organic light-emitting diodes  

NASA Astrophysics Data System (ADS)

Organic light-emitting diodes (OLEDs) are among the most promising organic semiconductor devices. The recently reported external quantum efficiencies (EQEs) of 29–30% for green and blue phosphorescent OLEDs are considered to be near the limit for isotropically oriented iridium complexes. The preferred orientation of transition dipole moments has not been thoroughly considered for phosphorescent OLEDs because of the lack of an apparent driving force for a molecular arrangement in all but a few cases, even though horizontally oriented transition dipoles can result in efficiencies of over 30%. Here we use quantum chemical calculations to show that the preferred orientation of the transition dipole moments of heteroleptic iridium complexes (HICs) in OLEDs originates from the preferred direction of the HIC triplet transition dipole moments and the strong supramolecular arrangement within the co-host environment. We also demonstrate an unprecedentedly high EQE of 35.6% when using HICs with phosphorescent transition dipole moments oriented in the horizontal direction.

Kim, Kwon-Hyeon; Lee, Sunghun; Moon, Chang-Ki; Kim, Sei-Yong; Park, Young-Seo; Lee, Jeong-Hwan; Woo Lee, Jin; Huh, June; You, Youngmin; Kim, Jang-Joo

2014-09-01

125

Dye Painting!  

ERIC Educational Resources Information Center

This resource provides practical instructions for applying color and design directly to fabric. Basic information about the dye painting process is given. The guide addresses the technical aspects of fabric dye and color use and offers suggestions for fabric manipulation and dye application in order to achieve various design effects. This…

Johnston, Ann

126

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

Federal Register 2010, 2011, 2012, 2013

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

2011-01-20

127

Acaricidal activities of the essential oils from several medicinal plants against the carmine spider mite ( Tetranychus cinnabarinus Boisd.) (Acarina: Tetranychidae)  

Microsoft Academic Search

A screening for pesticidal activity of plant extracts with some known medicinal attributes could lead to the discovery of new agents for pest control. In the backdrop of recent revival of interest in developing plant-based insecticides, the present study was carried out to find an alternative to synthetic miticides currently used in the control of the devastating greenhouse pest, carmine

Erdal Sertkaya; Kamuran Kaya; Soner Soylu

2010-01-01

128

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

PubMed

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

De Angelis, Filippo

2014-11-18

129

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

Microsoft Academic Search

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

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

2010-01-01

130

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

Microsoft Academic Search

Ultrashort pulses of duration ~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.

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

2003-01-01

131

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

SciTech Connect

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

Schmidt, J.; Penzkofer, A.

1989-08-01

132

Comparative study of UV/TiO2, UV/ZnO and photo-Fenton processes for the organic reactive dye degradation in aqueous solution.  

PubMed

In this study advanced oxidation processes (AOPs), UV/TiO(2), UV/ZnO and photo-Fenton, were applied in order to degrade C.I. Reactive Red 45 (RR45) dye in aqueous solution. The effects of key operating parameters, such as initial pH, catalyst and hydrogen peroxide dosage as well as the effect of initial dye concentration on decolorization and mineralization extents were studied. Primary objective was to determine the optimal conditions for each of the processes. The influence of added zeolite on the process efficiency was also studied. UV/vis spectrophotometric and total organic carbon (TOC) measurements were performed for determination of decolorization and mineralization extents. It has been found that photo-Fenton process was the most efficient with 74.2% TOC removal and complete color removal achieved after a 1h treatment. PMID:17400374

Peternel, Igor T; Koprivanac, Natalija; Bozi?, Ana M Loncari?; Kusi?, Hrvoje M

2007-09-01

133

X-ray photoelectron and optical absorption spectroscopic studies on the dye chlorodiane blue, used as a carrier generation molecule in organic photoconductors  

SciTech Connect

The dye chlorodiane blue, used as a carrier generation molecule in organic photoconductors, is characterized via optical absorption and X-ray photoelectron spectroscopy, and the results are interpreted on the basis of ab initio quantum mechanical molecular models. These data indicate that chlorodiane blue exists as azo-enol and hydrazone-quinone chemical structures and it is the hydrazone-quinone form that provides the higher xerographic gain in electrophotographic applications. Optimized geometries, atomic charges, and molecular orbital plots and energies are reported for both the azo-enol and hydrazone-quinone forms of chlorodiane blue. The two structural forms of the dye are experimentally distinguishable via both optical absorption and X-ray photoelectron spectroscopy, and the wavelength and chemical shifts, respectively, are interpreted via the theoretical results. 29 refs., 9 figs., 4 tabs.

Pacansky, J.; Waltman, R.J. [IBM Almaden Research Center, San Jose, CA (United States)

1992-07-01

134

Degradation of Dye Wastewater by ns-Pulse DBD Plasma  

NASA Astrophysics Data System (ADS)

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

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

2013-09-01

135

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

PubMed

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

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

2004-06-01

136

Highly efficient decomposition of organic dyes by aqueous-fiber phase transfer and in situ catalytic oxidation using fiber-supported cobalt phthalocyanine.  

PubMed

A novel metallophthalocyanine derivative, cobalt tetra (2,4-dichloro-1,3,5-triazine) aminophthalocyanine (Co-TDTAPc), was prepared and immobilized on cellulosic fiber by covalent bond to obtain a supported oxidation catalyst (Co-TDTAPc-F). Co-TDTAPc-F/H202 system based on phase-transfer catalytic oxidation for decomposing dyes, including acid, reactive, and direct dyes, has been investigated thoroughly. Compared to traditional adsorption technologies and advanced oxidation processes (AOPs) for dye treatment, Co-TDTAPc-F/H202 combines the advantages of both and is more efficient and more effective. Azo dyes such as C. I. Acid Red 1 (AR1) can be quickly adsorbed onto/into the fiber from aqueous solution and decomposed in situ simultaneously in the presence of Co-TDTAPc-F and H2O2. It has been found that the reaction process is not affected by the visible light. Furthermore, it turns the negative effect of NaCl normally observed in homogeneous catalysis into positive one. The catalytic reaction can proceed at a wide pH range from acidic to alkaline. In 60 min, more than 98% of AR1 was eliminated at initial pH 2. In 90 min, about 40% of the carbon was found mineralized as determined by the analysis of the residual total organic carbon. The high-performance liquid chromatography result indicated that a substantial amount of the starting AR1 was converted to other organic products, while gas chromatography/mass spectrometry analysis showed the rest of the carbon existed mainly as small molecular biodegradable aliphatic carboxylic compounds such as oxalic acid, malonic acid, and maleic acid, etc. Co-TDTAPc-F is stable, causes no secondary pollution, and remains efficient in repetitive test cycles with no obvious degradation of catalytic activity. PMID:17937309

Chen, Wenxing; Lu, Wangyang; Yao, Yuyuan; Xu, Minhong

2007-09-01

137

Hair Dyes  

Microsoft Academic Search

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

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

138

Journal of Fluorescence. Vol. 8. No. 1. 1998 Fluorescence of Organic Dyes in Lipid Membranes: Site of  

E-print Network

, which varied the viscosity and refractive index of the aqueous solution. The combined effect to the aqueous phase, for which the fluorescence lifetime increased systematically with sucrose (viscosity effect. The variation of the lifetime of the membrane-bound dye was studied as a function of the sucrose concentration

Mallela, Krishna M. G.

139

Facile assembly of hybrid materials containing polyoxometalate cluster anions and organic dye cations: crystal structures and initial spectral characterization.  

PubMed

Salts of the pararosaniline dye cation and four polyoxometalate cluster anions have been isolated under both ambient and hydrothermal conditions; structural and initial spectroscopic data are consistent with significant perturbation of ion electronic states induced by charge-assisted N-H---O hydrogen bonds. PMID:18209794

Xie, Jingli; Abrahams, Brendan F; Wedd, Anthony G

2008-02-01

140

Biological parameters of Cydnodromus picanus and Phytoseiulus persimilis raised on the carmine spider mite, Tetranychus cinnabarinus (Acari: Phytoseiidae, Tetranychidae)  

Microsoft Academic Search

V. Tello, R. Vargas, J. Araya, and A. Cardemil. 2009. Biological parameters of Cydnodromus picanus and Phytoseiulus persimilis raised on the carmine spider mite Tetranychus cinnabarinus (Acari: Phytoseiidae, Tetranychidae). Cien. Inv. Agr. 36(2):277-290. The postembryonic development, consumption and life table parameters of Cydnodromus picanus Ragusa and Phytoseiulus persimilis (Athias-Henriot) were studied at 29.44 ± 1.47 °C and 42.35 ± 5.01%

Víctor Tello; Robinson Vargas; Jaime Araya; Antonieta Cardemil

2009-01-01

141

Spectrophotometric determination of nitrite based on its catalytic effect on the oxidation of carminic acid by bromate.  

PubMed

A highly sensitive and selective method is described for the determination of trace amounts of nitrite based on its effect on the oxidation of carminic acid with bromate. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of carminic acid at 490 nm after 3 min of mixing the reagents. The optimum reaction conditions were 1.8x10(-1) mol l(-1) H(2)SO(4), 3.8x10(-3) mol l(-1) KBrO(3), and 1.2x10(-4) mol l(-1) carminic acid at 30 degrees C. By using the recommended procedure, the calibration graph was linear from 0.2 to 14 ng ml(-1) of nitrite; the detection limit was 0.04 ng ml(-1); the R.S.D. for six replicate determinations of 6 ng ml(-1) was 1.7%. The method is mostly free from interference, especially from large amounts of nitrate and ammonium ions. The proposed method was applied to the determination of nitrite in rain and river water. PMID:18967267

Manzoori, J L; Sorouraddin, M H; Haji-Shabani, A M

1998-08-01

142

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

PubMed

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

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

2009-12-15

143

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

NASA Astrophysics Data System (ADS)

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

Liu, Wei-Ting; Huang, Wen-Yao

2012-10-01

144

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

PubMed Central

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

Solis, A.; Perea, F.; Solis, M.; Manjarrez, N.; Perez, H. I.; Cassani, J.

2013-01-01

145

Nanoparticles of zinc sulfide doped with manganese, nickel and copper as nanophotocatalyst in the degradation of organic dyes.  

PubMed

Nanoparticles of zinc sulfide as undoped and doped with manganese, nickel and copper were used as photocatalyst in the photodegradation of methylene blue and safranin as color pollutants. Photoreactivity of doped zinc sulfide was varied with dopant, mole fraction of dopant to zinc ion, pH of solution, dosage of photocatalyst and concentration of dye. The characterization of nanoparticles was studied using X-ray powder diffraction (XRD) patterns and UV-vis spectra. The maximum degradation efficiency was obtained in the presence of Zn(0.98)Mn(0.02)S, Zn(0.94)Ni(0.06)S and Zn(0.90)Cu(0.10)S as nanophotocatalyst. The effect of dosage of photocatalyst was studied in the range of 20-250 mg/L. It was seen that 150.0 mg/L of photocatacyst is an optimum value for the dosage of photocatalyst. The most degradation efficiency was obtained in alkaline pH of 11.0 with study of photodegradation in pH amplitude of 2-12. The degradation efficiency was decreased in dye concentrations above of 5.0 mg/L for methylene blue and safranin dyes. In the best conditions, the degradation efficiency was obtained 87.3-95.6 and 85.4-93.2 for methylene blue and safranin, respectively. PMID:18603365

Pouretedal, Hamid Reza; Norozi, Abbas; Keshavarz, Mohammad Hossein; Semnani, Abolfazl

2009-03-15

146

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

PubMed

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

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

2014-01-15

147

Dye Painting with Fiber Reactive Dyes  

ERIC Educational Resources Information Center

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…

Benjamin-Murray, Betsy

1977-01-01

148

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

SciTech Connect

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

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

2013-02-05

149

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

NASA Astrophysics Data System (ADS)

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

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

2010-02-01

150

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

Microsoft Academic Search

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

Rajesh Kumar Sani; Uttam Chand Banerjee

1999-01-01

151

J-Aggregates of Organic Dye Molecules Complexed with Iron Oxide Nanoparticles for Imaging-Guided Photothermal Therapy Under 915-nm Light.  

PubMed

Recently, the development of nano-theranostic agents aiming at imaging guided therapy has received great attention. In this work, a near-infrared (NIR) heptamethine indocyanine dye, IR825, in the presence of cationic polymer, polyallylamine hydrochloride (PAH), forms J-aggregates with red-shifted and significantly enhanced absorbance. After further complexing with ultra-small iron oxide nanoparticles (IONPs) and the followed functionalization with polyethylene glycol (PEG), the obtained IR825@PAH-IONP-PEG composite nanoparticles are highly stable in different physiological media. With a sharp absorbance peak, IR825@PAH-IONP-PEG can serve as an effective photothermal agent under laser irradiation at 915 nm, which appears to be optimal in photothermal therapy application considering its improved tissue penetration compared with 808-nm light and much lower water heating in comparison to 980-nm light. As revealed by magnetic resonance (MR) imaging, those nanoparticles after intravenous injection exhibit high tumor accumulation, which is then harnessed for in vivo photothermal ablation of tumors, achieving excellent therapeutic efficacy in a mouse tumor model. This study demonstrates for the first time that J-aggregates of organic dye molecules are an interesting class of photothermal material, which when combined with other imageable nanoprobes could serve as a theranostic agent for imaging-guided photothermal therapy of cancer. PMID:24976309

Song, Xuejiao; Gong, Hua; Liu, Teng; Cheng, Liang; Wang, Chao; Sun, Xiaoqi; Liang, Chao; Liu, Zhuang

2014-11-01

152

Layered double hydroxide-carbon dot composite: high-performance adsorbent for removal of anionic organic dye.  

PubMed

It would be of significance to design a green composite for efficient removal of contaminants. Herein, we fabricated a facile and environmentally friendly composite via direct assembly of surface passivated carbon dots with abundant oxygen-containing functional groups on the surface of the positively charged layered double hydroxide (LDH). The resulting LDH-carbon dot composites were characterized by X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and N2 adsorption-desorption technique. The adsorption performances of the resulting LDH-carbon dot composites were evaluated for the removal of anionic methyl blue dye. Taking advantage of the combined benefits of LDH and carbon dots, the as-prepared composites exhibited high uptake capability of methyl blue (185 mg/g). The adsorption behavior of this new adsorbent fitted well with Langmuir isotherm and the pseudo-second-order kinetic model. The reasons for the excellent adsorption capacity of methyl blue on the surface of the LDH-carbon dot hybrid were further discussed. A probable mechanism was speculated to involve the cooperative contributions of hydrogen bonding between methyl blue and carbon dots and electrostatic attraction between methyl blue and LDH, in the adsorption process. This work is anticipated to open up new possibilities in fabricating LDH-carbon dot materials in dealing with anionic dye pollutants. PMID:25313875

Zhang, Manlin; Yao, Qingfeng; Lu, Chao; Li, Zenghe; Wang, Wenxing

2014-11-26

153

Surface-enhanced Raman scattering study of organic pigments using silver and gold nanoparticles prepared by pulsed laser ablation  

NASA Astrophysics Data System (ADS)

The identification of pigments used in ancient times represents an interesting task in order to discriminate a production of a precise geographic area or to trace out the ancient commercial networks. Conventional micro-Raman spectroscopy (MRS), being a non-destructiveness technique, has been largely used for the analysis of dyes. Nevertheless several pigments, especially of organic origin, show weak Raman activity beside a strong a fluorescence that prevents their identification. Surface enhanced Raman scattering (SERS) can address such difficulties. The presence of noble metal nanoparticles induces a giant amplification of the Raman signal beside the fluorescence quenching. In this work we present the use of gold and silver nanoparticles to enhance the Raman signal of some commercial red organic dyes: bazilwood, dragon's blood, carmine and madder lake. The nanoparticles were prepared adopting two approaches: (1) ablating metallic targets in water using a pulsed Nd:YAG laser at 532 nm and (2) depositing the nanoparticles on glass substrates by means of a KrF excimer laser ablation process, performed in a controlled argon atmosphere.

Fazio, E.; Trusso, S.; Ponterio, R. C.

2013-05-01

154

In vivo and in vitro decolorization of synthetic dyes by laccase from solid state fermentation with Trametes sp. SYBC-L4.  

PubMed

Synthetic decolorization of dyes through solid cassava residue substrate fermentation with Trametes sp. SYBC-L4 via in vivo and in vitro processes was investigated in this study. Effects of pH and mediator (1-hydroxybenzotriazole, HBT) concentration on dyes decolorization were evaluated. In vitro, decolorization ratios of dyes differed considerably in pH and increased with the increasing of HBT concentration. Crude laccase (50 U/L) derived from Trametes sp. SYBC-L4 decolorized 67.91 ± 1.25 % Congo red (100 mg/L), 94.58 ± 1.05 % aniline blue (100 mg/L) and 99.02 ± 0.54 % indigo carmine (100 mg/L) with 2.5 mM HBT at pH 4.5 in 36 h of incubation. In vivo, decolorization ratios of dyes were not enhanced by usage of the mediator. After 10 days of fermentation, decolorization ratio of Congo red (1,000 mg/kg), aniline blue (1,000 mg/kg) and indigo carmine (1,000 mg/kg) was 57.82 ± 0.84, 92.53 ± 1.12 and 97.26 ± 1.92 % without the usage of mediator at pH 4.5, respectively. Moreover, there was no obvious difference between the in vivo decolorization of aniline blue and indigo carmine in the pH range of 3.0-9.0. Results showed that Trametes sp. SYBC-L4 had great potential to be used for dyes decolorization via in vivo and in vitro processes. Moreover, in terms of pH range and mediator, in vivo decolorization with Trametes sp. SYBC-L4 was more advantageous since laccase mediator was needless and the applicable range of pH was broader. PMID:24951916

Li, Hui-Xing; Zhang, Rui-Jing; Tang, Lei; Zhang, Jian-Hua; Mao, Zhong-Gui

2014-12-01

155

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

PubMed

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

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

2013-07-10

156

Novel polymer gel electrolyte with organic solvents for quasi-solid-state dye-sensitized solar cells.  

PubMed

A cross-linked copolymer was previously synthesized from poly(oxyethylene) diamine (POE-amine) and an aromatic anhydride and cured to generate an amide-imide cross-linking structure. The copolymer containing several chemical groups such as POE, amido acids, and imide, enabled to absorb liquid electrolytes in methoxypropionitrile (MPN) for suitable uses in dye-sensitized solar cells. To establish the advantages of polymer gel electrolytes (PGE), the same copolymer was studied by using different electrolyte solvents including propylene carbonate (PC), dimethylformamide, and N-methyl-2-pyrrolidone, and shown their long-term stability. The morphology of the copolymer after absorbing liquid electrolytes in these solvents was proven the same as a 3D interconnected nanochannels, evidenced field emission-scanning electron microscopy. Among these solvents, PC was selected as the optimized PGE, which demostrated a higher power conversion efficiency (8.31%) than that of the liquid electrolyte (7.89%). In particular, the long-term stability of only a 5% decrease in the cell efficiency after 1000 h of testing was achieved. It was proven the developed copolymer as PGE was versatile for different solvents showing high efficiency and long-term durability. PMID:25296883

Shen, Sheng-Yen; Dong, Rui-Xuan; Shih, Po-Ta; Ramamurthy, Vittal; Lin, Jiang-Jen; Ho, Kuo-Chuan

2014-11-12

157

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

NASA Astrophysics Data System (ADS)

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

Ku, Zhiliang; Rong, Yaoguang; Han, Hongwei

2013-10-01

158

Dye loading of unimolecular, amphiphilic polymeric nanocontainers  

Microsoft Academic Search

Unimolecular, amphiphilic polymeric nanocontainers based on poly(2-vinylpyridine)-b-polystyrene-polymacromonomers are dispersed in organic solvents and loaded with different hydrophilic dyes in solution. The poly-2-vinylpyridine core of the nanocontainers is responsible for the dye uptake, whereas the polystyrene corona grants the solubility and stabilization of the particles. The nanocontainers are 20–30nm in diameter and possess an excellent ability to sequester dye molecules up

Michael Groß; Michael Maskos

2005-01-01

159

Dye laser amplifier  

DOEpatents

An improved dye laser amplifier is disclosed. The efficiency of the dye lr 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.

Moses, Edward I. (Livermore, CA)

1992-01-01

160

Femtosecond to millisecond studies of electron transfer processes in a donor-(?-spacer)-acceptor series of organic dyes for solar cells interacting with titania nanoparticles and ordered nanotube array films.  

PubMed

Time-resolved emission and absorption spectroscopy are used to study the photoinduced dynamics of forward and back electron transfer processes taking place between a recently synthesized series of donor-(?-spacer)-acceptor organic dyes and semiconductor films. Results are obtained for vertically oriented titania nanotube arrays (inner diameters 36 nm and 70 nm), standard titania nanoparticles (25 nm diameter) and, as a reference, alumina nanoparticle (13 nm diameter) films. The studied dyes contain a triphenylamine group as an electron donor, cyanoacrylic acid part as an electron acceptor, and differ by the substituents in a spacer group that causes a shift of its absorption spectra. Despite a red-shift of the dye absorption band resulting in an improved response to the solar spectrum, smaller electron injection rates and smaller extinction coefficients result in reduced dye sensitized solar cell (DSSC) conversion efficiencies. For the most efficient dye, TPC1, electron injection from the hot locally excited state to titania on a time scale of about 100 fs is suggested, while from the relaxed charge transfer state it proceeds in a non-exponential way with time constants from 1 ps to 50 ps. Our results imply that the latter process involves the trap states below the conduction band edge (or the sub-bandgap tail of the acceptor states), localized close to the dye radical cation, and is accompanied by fast electron recombination to the parent dye's ground state. This process should limit the efficiency of DSSCs made using these types of organic dyes. The residual, slower recombination can be described by a stretched exponential decay with a characteristic time of 0.5 ?s and a dispersion parameter of 0.33. Both the electron injection and back electron transfer dynamics are similar in titania nanoparticles and nanotubes. Variations between the two film types are only found in the time resolved emission transients, which are explained in terms of the difference in local electric fields affecting the position of the emission bands. PMID:22258566

Zió?ek, Marcin; Cohen, Boiko; Yang, Xichuan; Sun, Licheng; Paulose, Maggie; Varghese, Oomman K; Grimes, Craig A; Douhal, Abderrazzak

2012-02-28

161

A Near-Infrared Dithieno[2,3-a:3',2'-c]phenazine-Based Organic Co-Sensitizer for Highly Efficient and Stable Quasi-Solid-State Dye-Sensitized Solar Cells.  

PubMed

A novel near-infrared (NIR) organic sensitizer FNE53 with a strong electron-withdrawing unit, dithieno[2,3-a:3',2'-c]phenazine, has been designed and synthesized for quasi-solid-state dye-sensitized solar cells (DSSCs). By simply fusing the two thiophene rings on quinoxaline unit in sensitizer FNE48, the intramolecular charge transfer (ICT) band bathochromically shifts from 542 nm for FNE48 to 629 nm for FNE53 in toluene solution. The absorption spectrum of sensitizer FNE53 covers the whole visible region and extends to the NIR region, which exhibits complementary absorption profile to another organic dye FNE46 based on quinoxaline. When FNE46 and FNE53 are used as cosensitizers for metal-free cocktail-type quasi-solid-state DSSCs, sensitizer FNE53 not only extends the photoresponse range but also suppresses the intermolecular interactions among the dye molecules. Therefore, the cocktail-type quasi-solid-state DSSC displays much higher IPCE value compared with that for the DSSC sensitizer based on FNE53 and a broader IPCE response in comparison to that for the DSSC sensitizers based on FNE46, respectively. After the molar ratio between the two cocktail dyes is optimized, the highest energy conversion efficiency of 8.04% is achieved in a metal-free quasi-solid-state DSSC cosensitized with FNE46 and FNE53, which exhibits good long-term stability after continuous light soaking for 1000 h. PMID:25291482

Lu, Xuefeng; Lan, Tian; Qin, Zhenwen; Wang, Zhong-Sheng; Zhou, Gang

2014-11-12

162

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

SciTech Connect

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

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

2006-04-01

163

Plasma induced degradation of Indigo Carmine by bipolar pulsed dielectric barrier discharge(DBD) in the water-air mixture.  

PubMed

Degradation of the Indigo Carmine (IC) by the bipolar pulsed DBD in water-air mixture was studied. Effects of various parameters such as gas flow rate, solution conductivity, pulse repetitive rate and ect., on color removal efficiency of dying wastewater were investigated. Concentrations of gas phase o3 and aqueous phase H2O2 under various conditions were measured. Experimental results showed that air bubbling facilitates the breakdown of water and promotes generation of chemically active species. Color removal efficiency of IC solution can be greatly improved by the air aeration under various solution conductivities. Decolorization efficiency increases with the increase of the gas flow rate, and decreases with the increase of the initial solution conductivity. A higher pulse repetitive rate and a larger pulse capacitor C(p) are favorable for the decolorization process. Ozone and hydrogen peroxide formed decreases with the increase of initial solution conductivity. In addition, preliminary analysis of the decolorization mechanisms is given. PMID:15559817

Zhang, Ruo-Bing; Wu, Yan; Li, Guo-Feng; Wang, Ning-Hui; Li, Jie

2004-01-01

164

Dyeing behaviour of gamma irradiated cotton fabric using Lawson dye extracted from henna leaves (Lawsonia inermis)  

NASA Astrophysics Data System (ADS)

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.

Rehman, Fazal-ur; Adeel, Shahid; Qaiser, Summia; Ahmad Bhatti, Ijaz; Shahid, Muhammad; Zuber, Mohammad

2012-11-01

165

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

PubMed Central

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

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

166

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

PubMed

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

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

167

New Form of an Old Natural Dye: Bay-Annulated Indigo (BAI) as an Excellent Electron Accepting Unit for High Performance Organic Semiconductors.  

PubMed

A novel electron acceptor was synthesized from one-step functionalization of the readily available indigo dye. The resulting bay-annulated indigo (BAI) was utilized for the preparation of a series of novel donor-acceptor small molecules and polymers. As revealed experimentally and by theoretical calculations, substituted BAIs have stronger electron accepting characteristics when compared to several premier electron deficient building blocks. As a result, the donor-acceptor materials incorporating BAI acceptor possess low-lying LUMO energy levels and small HOMO-LUMO gaps. In situ grazing incidence wide-angle X-ray scattering studies of the thin films of BAI donor-acceptor polymers indicated improved crystallinity upon thermal treatment. Field effect transistors based on these polymers show excellent ambipolar transporting behavior, with the hole and electron mobilities reaching 1.5 and 0.41 cm(2) V(-1) s(-1), respectively, affirming BAI as a potent electron accepting unit for high performance organic electronic materials. PMID:25254646

He, Bo; Pun, Andrew B; Zherebetskyy, Danylo; Liu, Yao; Liu, Feng; Klivansky, Liana M; McGough, Alexandra M; Zhang, Benjamin A; Lo, Kelvin; Russell, Thomas P; Wang, Linwang; Liu, Yi

2014-10-22

168

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

NASA Astrophysics Data System (ADS)

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

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

2010-10-01

169

3D Hierarchical Rutile TiO2 and Metal-free Organic Sensitizer Producing Dye-sensitized Solar Cells 8.6% Conversion Efficiency  

NASA Astrophysics Data System (ADS)

Three-dimensional (3D) hierarchical nanoscale architectures comprised of building blocks, with specifically engineered morphologies, are expected to play important roles in the fabrication of `next generation' microelectronic and optoelectronic devices due to their high surface-to-volume ratio as well as opto-electronic properties. Herein, a series of well-defined 3D hierarchical rutile TiO2 architectures (HRT) were successfully prepared using a facile hydrothermal method without any surfactant or template, simply by changing the concentration of hydrochloric acid used in the synthesis. The production of these materials provides, to the best of our knowledge, the first identified example of a ledgewise growth mechanism in a rutile TiO2 structure. Also for the first time, a Dye-sensitized Solar Cell (DSC) combining a HRT is reported in conjunction with a high-extinction-coefficient metal-free organic sensitizer (D149), achieving a conversion efficiency of 5.5%, which is superior to ones employing P25 (4.5%), comparable to state-of-the-art commercial transparent titania anatase paste (5.8%). Further to this, an overall conversion efficiency 8.6% was achieved when HRT was used as the light scattering layer, a considerable improvement over the commercial transparent/reflector titania anatase paste (7.6%), a significantly smaller gap in performance than has been seen previously.

Lin, Jianjian; Heo, Yoon-Uk; Nattestad, Andrew; Sun, Ziqi; Wang, Lianzhou; Kim, Jung Ho; Dou, Shi Xue

2014-08-01

170

New Organic Donor-Acceptor-?-Acceptor Sensitizers for Efficient Dye-Sensitized Solar Cells and Photocatalytic Hydrogen Evolution under Visible-Light Irradiation.  

PubMed

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

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

171

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

NASA Astrophysics Data System (ADS)

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

Mawyin, Jose Amador

172

Coordination compounds of manganese(II) with polyamines - catalysts of the oxidation of organic dyes by hydrogen peroxide  

SciTech Connect

The peroxidase activity of complexes of manganese(II) with polyamines has been characterized. A comparison of the original and literature data has led to the conclusion that the oxidation of organic substrates having some complexing ability with respect to Manganese(II) in Mn(II)-ligand-H/sub 2/O/sub 2/-S systems takes place according to an inner-sphere ion-molecule mechanism. In cases in which the substrate does not have any complexing ability with respect to Manganese(II), the oxidation process takes place according to an outer-sphere mechanism.

Batyr, D.G.; Isak, V.G.; Kirienko, A.A.; Kharitonov, Yu.Ya.

1987-02-01

173

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

PubMed

Two new carbazole-based organic dye sensitizers are designed and investigated in silico. These dyes are designed through chemical modifications of the ?-conjugated bridge of a reference organic sensitizer known as Carbz-PAHTDDT (S9) dye. The aim of designing these dyes was to reduce the energy gap between their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and to red-shift their absorption response compared to those of the reference S9 dye sensitizer. This reference dye has a reported promising efficiency when coupled with ferrocene-based electrolyte composition. To investigate geometric and electronic structure, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were conducted on the new dyes as well as the reference dye. The present study indicated that the long-range correction to the theoretical model in the TD-DFT simulation is important to produce accurate absorption wavelengths. The theoretical studies have shown a reduced HOMO-LUMO gap and red-shifted absorption spectra for both of the new candidate dyes. In particular, the new S9-D1 dye is found to have significant reduced HOMO-LUMO energy gap, greater push-pull character and higher wavelengths of absorption when compared to the reference dye. Such findings suggest that the new dyes are promising and suitable for optoelectronic applications. PMID:24595721

Mohammadi, Narges; Wang, Feng

2014-03-01

174

Ultrasonic assisted dyeing  

Microsoft Academic Search

The dyeing of wool fabrics using lac as a natural dye has been studied in both conventional and ultrasonic techniques. The extractability of lac dye from natural origin using power ultrasonic was also evaluated in comparison with conventional heating. The results of dye extraction indicate that power ultrasonic is rather effective than conventional heating at low temperature and short time.

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

2005-01-01

175

A double-acceptor as a superior organic dye design for p-type DSSCs: high photocurrents and the observed light soaking effect.  

PubMed

Herein, we report three novel single donor double acceptor dyes, BH2, 4, and 6, for use in p-type dye sensitized solar cells (DSSCs). BH4 yields one of the highest photocurrents, 7.4 mA cm(-2), to date. The high performance is achieved via a shorter synthetic route and no exotic materials or cell-building techniques. We suggest a structural principle when building dyes whereby one adopts a double acceptor/single anchor when a triphenylamine moiety is incorporated into a dye for p-type DSSCs. This strategy increases the molar extinction coefficient while simultaneously reducing the number of synthetic steps. The molar extinction coefficients (99?980 M(-1) cm(-1)) reported herein are among the highest reported. Finally, we report the first-ever-observed light soaking effect in p-type DSSCs. PMID:25360820

Click, Kevin A; Beauchamp, Damian R; Garrett, Benjamin R; Huang, Zhongjie; Hadad, Christopher M; Wu, Yiying

2014-12-21

176

Comparison of dye doping and ultrathin emissive layer in white organic light-emitting devices with dual emissive layers  

NASA Astrophysics Data System (ADS)

White organic light-emitting devices (WOLEDs) with combined doping emissive layer (EML) and ultrathin EML have been fabricated to investigate the effect of each EML on the electroluminescent (EL) performance of the WOLEDs. Through tailoring doping concentration of bis[(4,6-difluorophenyl)-pyridinato-N,C2'](picolinate) iridium(III) (FIrpic) and thickness of ultrathin bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2'] iridium (acetylacetonate) [(tbt)2Ir(acac)] EML, it is found that the change in the doping ratio of FIrpic significantly influenced the EL efficiencies and spectra, while the alteration of ultrathin EML thickness had much milder effect on the EL performance. The results indicated that ultrathin EML is in favor of reproducibility in mass production compared with doping method.

Wang, Xu; Qi, Yige; Yu, Junsheng

2014-09-01

177

Patterns of dye coupling involving serotonergic neurons provide insights into the cellular organization of a central complex lineage of the embryonic grasshopper Schistocerca gregaria.  

PubMed

All eight neuroblasts from the pars intercerebralis of one protocerebral hemisphere whose progeny contribute fibers to the central complex in the embryonic brain of the grasshopper Schistocerca gregaria generate serotonergic cells at stereotypic locations in their lineages. The pattern of dye coupling involving these neuroblasts and their progeny was investigated during embryogenesis by injecting fluorescent dye intracellularly into the neuroblast and/or its progeny in brain slices. The tissue was then processed for anti-serotonin immunohistochemistry. A representative lineage, that of neuroblast 1-3, was selected for detailed study. Stereotypic patterns of dye coupling were observed between progeny of the lineage throughout embryogenesis. Dye injected into the soma of a serotonergic cell consistently spread to a cluster of between five and eight neighboring non-serotonergic cells, but never to other serotonergic cells. Dye injected into a non-serotonergic cell from such a cluster spread to other non-serotonergic cells of the cluster, and to the immediate serotonergic cell, but never to further serotonergic cells. Serotonergic cells tested from different locations within the lineage repeat this pattern of dye coupling. All dye coupling was blocked on addition of an established gap junctional blocker (n-heptanol) to the bathing medium. The lack of coupling among serotonergic cells in the lineage suggests that each, along with its associated cluster of dye-coupled non-serotonergic cells, represents an independent communicating pathway (labeled line) to the developing central complex neuropil. The serotonergic cell may function as the coordinating element in such a projection system. PMID:21190117

Boyan, George; Niederleitner, Bertram

2011-03-01

178

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

PubMed Central

A set polyethylene glycol (PEG) appended BODIPY architectures (BOPEG1 – BOPEG3) have been prepared and studied in CH2Cl2, H2O:CH3CN (1:1) and aqueous solutions. BOPEG1 and BOPEG2 both contain a short PEG chain and differ in substitution about the BODIPY framework. BOPEG3 is comprised of a fully substituted BODIPY moiety linked to a PEG polymer that is roughly 13 units in length. The photophysics and electrochemical properties of these compounds have been thoroughly characterized in CH2Cl2 and aqueous CH3CN solutions. The behavior of BOPEG1 – BOPEG3 correlates with established rules of BODIPY stability based on substitution about the BODIPY moiety. ECL for each of these compounds was also monitored. BOPEG1, which is unsubstituted at the 2- and 6-positions dimerized upon electrochemical oxidation while BOPEG2, which contains ethyl groups at the 2- and 6-positions, was much more robust and served as an excellent ECL luminophore. BOPEG3 is highly soluble in water due to the long PEG tether and demonstrated modest ECL activity in aqueous solutions using tri-n-propylamine (TPrA) as a coreactant. As such, BOPEG3 represents the first BODIPY derivative that has been shown to display ECL in water without the need for an organic cosolvent, and marks an important step in the development of BODIPY based ECL probes for various biosensing applications. PMID:23626863

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

2013-01-01

179

Chalcogenopyrylium dyes as differential modulators of organic anion transport by multidrug resistance protein 1 (MRP1), MRP2, and MRP4.  

PubMed

Multidrug resistance proteins (MRPs) mediate the ATP-dependent efflux of structurally diverse compounds, including anticancer drugs and physiologic organic anions. Five classes of chalcogenopyrylium dyes (CGPs) were examined for their ability to modulate transport of [(3)H]estradiol glucuronide (E(2)17?G; a prototypical MRP substrate) into MRP-enriched inside-out membrane vesicles. Additionally, some CGPs were tested in intact transfected cells using a calcein efflux assay. Sixteen of 34 CGPs inhibited MRP1-mediated E(2)17?G uptake by >50% (IC50 values: 0.7-7.6 µM). Of 9 CGPs with IC50 values ?2 µM, two belonged to class I, two to class III, and five to class V. When tested in the intact cells, only 4 of 16 CGPs (at 10 µM) inhibited MRP1-mediated calcein efflux by >50% (III-1, V-3, V-4, V-6), whereas a fifth (I-5) inhibited efflux by just 23%. These five CGPs also inhibited [(3)H]E(2)17?G uptake by MRP4. In contrast, their effects on MRP2 varied, with two (V-4, V-6) inhibiting E(2)17?G transport (IC(50) values: 2.0 and 9.2 µM) and two (V-3, III-1) stimulating transport (>2-fold), whereas CGP I-5 had no effect. Strikingly, although V-3 and V-4 had opposite effects on MRP2 activity, they are structurally identical except for their chalcogen atom (Se versus Te). This study is the first to identify class V CGPs, with their distinctive methine or trimethine linkage between two disubstituted pyrylium moieties, as a particularly potent class of MRP modulators, and to show that, within this core structure, differences in the electronegativity associated with a chalcogen atom can be the sole determinant of whether a compound will stimulate or inhibit MRP2. PMID:23530018

Myette, Robert L; Conseil, Gwenaëlle; Ebert, Sean P; Wetzel, Bryan; Detty, Michael R; Cole, Susan P C

2013-06-01

180

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

PubMed Central

Multidrug resistance proteins (MRPs) mediate the ATP-dependent efflux of structurally diverse compounds, including anticancer drugs and physiologic organic anions. Five classes of chalcogenopyrylium dyes (CGPs) were examined for their ability to modulate transport of [3H]estradiol glucuronide (E217?G; a prototypical MRP substrate) into MRP-enriched inside-out membrane vesicles. Additionally, some CGPs were tested in intact transfected cells using a calcein efflux assay. Sixteen of 34 CGPs inhibited MRP1-mediated E217?G uptake by >50% (IC50 values: 0.7–7.6 µM). Of 9 CGPs with IC50 values ?2 µM, two belonged to class I, two to class III, and five to class V. When tested in the intact cells, only 4 of 16 CGPs (at 10 µM) inhibited MRP1-mediated calcein efflux by >50% (III-1, V-3, V-4, V-6), whereas a fifth (I-5) inhibited efflux by just 23%. These five CGPs also inhibited [3H]E217?G uptake by MRP4. In contrast, their effects on MRP2 varied, with two (V-4, V-6) inhibiting E217?G transport (IC50 values: 2.0 and 9.2 µM) and two (V-3, III-1) stimulating transport (>2-fold), whereas CGP I-5 had no effect. Strikingly, although V-3 and V-4 had opposite effects on MRP2 activity, they are structurally identical except for their chalcogen atom (Se versus Te). This study is the first to identify class V CGPs, with their distinctive methine or trimethine linkage between two disubstituted pyrylium moieties, as a particularly potent class of MRP modulators, and to show that, within this core structure, differences in the electronegativity associated with a chalcogen atom can be the sole determinant of whether a compound will stimulate or inhibit MRP2. PMID:23530018

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

2013-01-01

181

The potential of middle eastern flora as a source of new safe bio-acaricides to control Tetranychus cinnabarinus , the carmine spider mite  

Microsoft Academic Search

Twenty-nine plant extracts of local species were evaluated for their potential as a source of bioactive ingredients with significant\\u000a acaricidal activity that could lead to the development of new and safe bio-acaricides. The crude extracts (70% ethanol) of\\u000a these plants were tested for their acaricidal activity against the carmine spider miteTetranychus cinnabarinus in a bioassay under controlled conditions. Mortality, repellency,

F. Mansour; H. Azaizeh; B. Saad; Y. Tadmor; F. Abo-Moch; O. Said

2004-01-01

182

Sensitively monitoring photodegradation process of organic dye molecules by surface-enhanced Raman spectroscopy based on Fe3O4@SiO2@TiO2@Ag particle.  

PubMed

Photodegradation of organic dye molecules has attracted extensive attention because of their high toxicity to water resources. Compared with traditional UV-visible spectroscopy, SERS technology can reflect more sensitively the catalytic degradation process occurring on the surface of the catalysts. In this paper, we report the synthesis and structure of Fe3O4@SiO2@TiO2@Ag composite, which integrates SERS active Ag nanostructure with catalytically active titania. The degradation of the typical dye molecule crystal violet (CV), as an example, is investigated in the presence of the as-prepared Fe3O4@SiO2@TiO2@Ag composite structure, which exhibits high catalytic activity and good SERS performance. At the same time, renewable photocatalytic activity was also investigated. PMID:25192200

Qin, Suhua; Cai, Wenya; Tang, Xianghu; Yang, Liangbao

2014-09-29

183

Dyeing of Jute Fabric Using Indigosol Dyes  

Microsoft Academic Search

Bleached jute fabric has been dyed with three indigosol dyes, namely Indigosol Violet I4R, Indigosol Golden Yellow IGK, and Indigosol Blue O4B, having different sensitivity to oxidation. Development stage (i.e., oxidation, neutralization, and soaping of the dyed fabric) plays the most important role for dyeing of jute fabric with indigosol dyes. Concentrations of chemicals in different processing steps such as

S. N. Chattopadhyay; N. C. Pan; A. K. Roy; A. Khan

2009-01-01

184

The potential of Lagenaria rootstock to confer resistance to the carmine spider mite, Tetranychus cinnabarinus (Acari: Tetranychidae) in Cucurbitaceae.  

PubMed

Antibiosis and resistance of six Cucurbita and two Lagenaria accessions to the carmine spider mite, Tetranychus cinnabarinus Boisduval, were evaluated in the laboratory. Significant differences among accessions were observed three days after the inoculation of detached leaf discs. The Lagenaria accessions, Slawi and Sus, proved to be the most resistant to mites, with average populations of mite eggs, 87 and 95%, respectively less than that of the susceptible C. pepo accession, Orangetti. The Cucurbita accessions, Tace, Brava, Tetsukabuto, Phoenix and TZ-148 had mite egg totals 4, 9, 13, 26 and 40%, respectively, less than those of accession Orangetti. The Sus accession of Lagenaria was resistant to T. cinnabarinus from the four-leaf stage until fruit set in laboratory and field tests. Grafting the susceptible Brava onto Sus rootstock increased the resistance of the scion to the same level as that of non-grafted Sus. Grafting the susceptible Cucumis melo Noy Yizre'el on resistant or susceptible rootstocks of Cucurbita and Lagenaria accessions did not affect its susceptibility to T. cinnabarinus. The results indicate that resistance to T. cinnabarinus can be transferred by grafting from Lagenaria stocks to Cucurbita scions but not in the opposite direction. PMID:10948370

Edelstein, M; Tadmor, Y; Abo-Moch, F; Karchi, Z; Mansour, F

2000-04-01

185

The dyeing of Lyocell fabric with direct dyes  

Microsoft Academic Search

Lyocell, cotton and viscose fabrics were dyed using four direct dyes. With the exception of the bordeaux dye used, dyeings on Lyocell were of slightly different colour to comparative dyeings on cotton and viscose; the colour strength (K\\/S) of the dyeings on Lyocell was lower than on cotton and viscose and the four dyes exhibited lower build-up character on Lyocell

S. M. Burkinshaw; R. Krishna

1995-01-01

186

Role of rare earth oxide nanoparticles (CeO2 and La2O3) in suppressing the photobleaching of fluorescent organic dyes.  

PubMed

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

Guha, Anubhav; Basu, Anindita

2014-05-01

187

Method of dye removal for the textile industry  

SciTech Connect

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.

Stone, M.L.

2000-07-25

188

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

NASA Astrophysics Data System (ADS)

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.

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

2014-02-01

189

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

PubMed

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

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

1987-12-18

190

Dye remover poisoning  

MedlinePLUS

... remover is a chemical used to remove dye stains. Dye remover poisoning occurs when someone swallows this ... by IV Medicines to treat pain Oxygen Surgical removal of burned skin (skin debridement) Washing of the ...

191

Analysis of dimeric cyanine-nucleic acid dyes by capillary zone electrophoresis in N,N-dimethylacetamide as non-aqueous organic solvent.  

PubMed

A method based on capillary zone electrophoresis is presented for the determination of the purity of commercial dimeric cyanine dyes (TOTO, YOYO, BOBO, all -1 and -3 species, LOLO-1, POPO-1) that are common as fluorescent probes for nucleic acid staining. These dyes are tetracharged cations, and have a strong tendency to interact with negatively charged centres, where they are rapidly adsorbed, especially from aqueous solutions. Thus anionic sites at the capillary wall must be avoided, and aqueous buffers are not suitable. The method introduced here avoids both complications, using non-aqueous N,N-dimethylacetamide as solvent, and suppressing the dissociation of silanol groups at the capillary surface due to selection of acidic separation conditions (20 mmol/l perchloric acid as background electrolyte). The present method enables the determination of the purity of all 10 dyes in less than 15 min. The selectivity of the method allows separation of at least five main and differentiating a number of unresolved minor contaminants as demonstrated in detail for TOTO-3 as an example. Quantitation (with 100% normalisation of the peak areas) of nine lots of this dye results in a purity between 33 and 87%. PMID:11990999

Muzikar, Jan; Rozing, Gerard; van de Goor, Tom; Eberwein, Christine; Kenndler, Ernst

2002-03-15

192

Dye Like A Natural  

NSDL National Science Digital Library

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

Yu, Julie

2010-01-01

193

Monitoring the dye impregnation time of nanostructured photoanodes for dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells (DSSCs) are getting increasing attention as low-cost, easy-to-prepare and colored photovoltaic devices. In the current work, in view of optimizing the fabrication procedures and understanding the mechanisms of dye attachment to the semiconductor photoanode, absorbance measurements have been performed at different dye impregnation times ranging from few minutes to 24 hours using UV-Vis spectroscopy. In addition to the traditional absorbance experiments, based on diffuse and specular reflectance on dye impregnated thin films and on the desorption of dye molecules from the photoanodes by means of a basic solution, an alternative in-situ solution depletion measurement, which enables fast and continuous evaluation of dye uptake, is presented. Photoanodes have been prepared with two different nanostructured semiconducting films: mesoporous TiO2, using a commercially available paste from Solaronix, and sponge-like ZnO obtained in our laboratory from sputtering and thermal annealing. Two different dyes have been analyzed: Ruthenizer 535-bisTBA (N719), which is widely used because it gives optimal photovoltaic performances, and a new metal-free organic dye based on a hemisquaraine molecule (CT1). Dye sensitized cells were fabricated using a customized microfluidic architecture. The results of absorbance measurements are presented and discussed in relation to the obtained solar energy conversion efficiencies and the incident photon-to-electron conversion efficiencies (IPCE).

Shahzad, N.; Pugliese, D.; Lamberti, A.; Sacco, A.; Virga, A.; Gazia, R.; Bianco, S.; Shahzad, M. I.; Tresso, E.; Pirri, C. F.

2013-06-01

194

Evaluation of Argentinean white rot fungi for their ability to produce lignin-modifying enzymes and decolorize industrial dyes.  

PubMed

The decolorizing capacity of 26 white rot fungi from Argentina was investigated. Extracellular production of ligninolytic enzymes by mycelium growing on solid malt extract/glucose medium supplemented with different dyes (Malachite Green, Azure B, Poly R-478, Anthraquinone Blue, Congo Red and Xylidine), dye decolorization and the relationship between these two processes were studied. Only ten strains decolorized all the dyes, all ten strains produced laccase, lignin peroxidase and manganese peroxidase on solid medium. However, six of the strains could not decolorize any of the dyes; all six strains tested negative for lignin peroxidase, and produced less than 0.05 U/g agar of manganese peroxidase. Comparing the isolates with the well-known dye-degrader Phanerochaete chrysosporium, a new fungus was identified: Coriolus versicolor f. antarcticus, potentially a candidate for use in biodecoloration processes. Eighteen day-old cultures of this fungus were able to decolorize in an hour 28%, 30%, 43%, 88% and 98% of Xylidine (24 mg/l), Poly R-478 (75 mg/l), Remazol Brilliant Blue R (9 mg/l), Malachite Green (6 mg/l) and Indigo Carmine (23 mg/l), respectively. Laccase activity was 0.13 U/ml, but neither lignin peroxidase nor manganese peroxidase were detected in the extracellular fluids for that day of incubation. PMID:15158509

Levin, L; Papinutti, L; Forchiassin, F

2004-09-01

195

Effect of mercerization and gamma irradiation on the dyeing behaviour of cotton using stilbene based direct dye  

NASA Astrophysics Data System (ADS)

The dyeing behaviour of mercerized and gamma irradiated cotton fabric using stilbene based direct dye has been investigated. The fabric was treated with different concentrations of alkali to optimize the mercerization. The optimum mercerized cotton fabric was irradiated to absorbed doses of 2, 4, 6, 8 and 10 kGy using Cs-137 gamma irradiator. Dyeing was performed using irradiated and un-irradiated cotton with dye solutions. The dyeing parameters such as temperature, time of dyeing, pH of dyeing solutions and salt concentration were optimized. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton in CIE Lab system using Spectra flash SF650. Methods suggested by International Standard Organization (ISO) were employed to study the effect of gamma irradiation on the colourfastness properties of dyed fabric. It was found that mercerized and irradiated cotton have not only improved the colour strength but enhanced the rating of fastness properties also.

Bhatti, Ijaz Ahmad; Adeel, Shahid; Fazal-ur-Rehman; Irshad, Misbah; Abbas, Muhammad

2012-07-01

196

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

PubMed

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. PMID:24681315

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

2014-07-15

197

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

Microsoft Academic Search

For the improvement of the conversion efficiency of CdS\\/CdTe solar cells by applying the wavelength conversion properties, the spectroscopic studies of the fluorescent laser dye Rhodamine 6G (Rh6G)-doped into polyvinylbutyral (PVB) and polymethylmethacrylate (PMMA) were carried out. It was found that all the photoluminescence excitation (PLE) spectra below 540 nm were effectively converted to photoluminescence (PL) spectra in the wavelength

Byung-Chul Hong; Katsuyasu Kawano

2004-01-01

198

Solid-state organic\\/inorganic hybrid solar cells based on conjugated polymers and dye-sensitized TiO 2 electrodes  

Microsoft Academic Search

Several efforts on using a dye-sensitized TiO2 nanocrystalline solar cell (nc-DSC) by replacing the liquid electrolyte with a solid-state analogy (by either a polymer electrolyte or a hole conducting material) intend to eliminate practical problems with sealing and degradation. Polymeric materials that behave as hole conductors are of practical interest as replacements for the liquid electrolyte, since they are inexpensive

D. Gebeyehu; C. J. Brabec; N. S. Sariciftci

2002-01-01

199

Photosemiconducting properties of holographic media based on ferrocenyl-containing cooligomers of glycidyl carbazole with these oligomers sensitized by organic dye  

Microsoft Academic Search

Spectral, photosemiconducting, and information properties of holographic recording media with films of glycidyl carbazole-butyl\\u000a glycidyl ether cooligomer, methylated ferrocenyl oligoglycidyl carbazole, and o-carboxybenzoyl ferrocene glycidyl ether cooligomer\\u000a with squaryl dye additives were studied. An increase in the holographic sensitivity and photoconductivity of recording media\\u000a with ferrocenyl-containing cooligomer films in comparison with media based on a glycidyl carbazole cooligomer was found.

N. A. Davidenko; S. V. Dehtarenko; Yu. P. Getmanchuk; A. A. Ishchenko; A. V. Kozinetz; L. I. Kostenko; E. V. Mokrinskaya; S. L. Studzinsky; V. A. Skryshevsky; N. A. Skulsky; O. V. Tretyak; N. G. Chuprina

2009-01-01

200

Modification of TiO? electrode with organic silane interposed layer for high-performance of dye-sensitized solar cells.  

PubMed

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

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

2014-04-23

201

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

PubMed

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

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

2014-11-19

202

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

PubMed

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

Mizutani, Takaharu

2009-01-01

203

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

PubMed Central

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

Mizutani, Takaharu

2009-01-01

204

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

Microsoft Academic Search

Reactive dyes are vastly used in dyeing and printing of cotton fibre. These dyes have a distinctive reactive nature due to active groups which form covalent bonds with –OH groups of cotton through substitution and\\/or addition mechanism. Among many methods used for dyeing cotton with reactive dyes, the Cold Pad Batch (CPB) method is relatively more environment friendly due to

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

2011-01-01

205

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

Microsoft Academic Search

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

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

2007-01-01

206

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

NASA Astrophysics Data System (ADS)

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

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

2012-05-01

207

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

NASA Astrophysics Data System (ADS)

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

Jiao, Yang; Ma, Wei; Meng, Sheng

2013-10-01

208

Synthesis and photovoltaic performance of new diketopyrrolopyrrole (DPP) dyes for dye-sensitized solar cells  

Microsoft Academic Search

Two new metal-free organic dyes (DPP-I and DPP-II) with diketopyrrolopyrrole (DPP) core were designed and synthesized, in which triphenylamine or N,N-bis(4-methoxyphenyl)benzenamine moieties was used as the electron donor, DPP units as the ?-conjugated bridge, and carboxylic acid group as the electron acceptor. Photophysical and electrochemical properties of two dyes were investigated by UV–vis spectrometry and cyclic voltammetry. Electrochemical measurement data

Fuling Guo; Sanyin Qu; Wenjun Wu; Jing Li; Weijiang Ying; Jianli Hua

2010-01-01

209

Upconverting Organic Dye Doped Core-Shell Nano-Composites for Dual-Modality NIR Imaging and Photo-Thermal Therapy  

PubMed Central

Nanotechnology approaches offer the potential for creating new optical imaging agents with unique properties that enable uses such as combined molecular imaging and photo-thermal therapy. Ideal preparations should fluoresce in the near-infrared (NIR) region to ensure maximal tissue penetration depth along with minimal scattering and light absorption. Due to their unique photophysical properties, upconverting ceramics such as NaYF4:Er3+,Yb3+ nanoparticles have become promising optical materials for biological imaging. In this work, the design and synthesis of NaYF4:Er3+,Yb3+@SiO2 core-shell nano-composites, which contain highly absorbing NIR carbocyanine dyes in their outer silica shell, are described. These materials combine optical emission (from the upconverting core nanoparticle) with strong NIR absorption (from the carbocyanine dyes incorporated into the shell) to enable both optical imaging and photo-thermal treatment, respectively. Ultimately, this hybrid composite nanomaterial approach imparts the ability to both visualize, via upconversion imaging, and treat, via photo-thermal heating, using two distinct optical channels. Proof-of-principle in vitro experiments are presented to demonstrate the combined imaging and photo-thermal properties of this new functional nano-composite. PMID:23606913

Shan, Guobin; Weissleder, Ralph; Hilderbrand, Scott A.

2013-01-01

210

Optical studies of dye-coated superconductor junctions  

SciTech Connect

The preparation and characterization of a new generation of optical sensors fabricated from high-temperature superconductor (HTSC) thin films is reported herein. These new hybrid devices are fashioned using HTSC thin films which are coated with organic dye overlayers. These systems are shown to respond selectively to those wavelengths which are absorbed strongly by the molecular dye. Methods for fabricating the superconductor element and depositing the dye layer are discussed. Moreover, resistivity versus temperature measurements before and after dye deposition are utilized to characterize these hybrid structures. The unique optical response properties of these hybrid sensors are also detailed.

Savoy, S.; Eames, S.; Jurbergs, D.; Zhao, J.; McDevitt, J.T. [Univ. of Texas, Austin, TX (United States). Dept. of Chemistry and Biochemistry

1996-12-31

211

The Presentation Carmine Gallo  

E-print Network

....................................................................................................................................................................6 Sell Dreams, Not Products into an art form. Whether you're a CEO, manager, entrepreneur, small business owner, or sales or marketing

212

Tie-Dye Chemistry  

NSDL National Science Digital Library

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

Cessna, Gretchen; Cessna, Stephen

2001-03-01

213

Molecular design of the diketopyrrolopyrrole-based dyes with varied donor units for efficient dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

Three types of novel diketopyrrolopyrrole-based organic dyes (Type 1-3) with phenyl unit as an additional ?-bridge and triphenylamine or phenothiazine as the donors are designed and synthesized for dye-sensitized solar cells (DSSCs). Type 1 dyes incorporating the donor segment directly to the diketopyrrolopyrrole core lead to a better electron communication between the donor and acceptor, allowing an efficient charge transfer process. Type 2 and Type 3 dyes with a phenyl unit between the donor and diketopyrrolopyrrole unit show lower delocalization of the excited state. Compared with Type 3 dyes, Type 1 dyes exhibit higher conjugated skeleton co planarity and shorter electron transfer distance from the donor to TiO2, resulting in the red-shifts of absorption and promotion of electron injection, respectively. Moreover, the dyes with triphenylamine as the donor display better UV performance and lower trend of aggregation than the dyes with phenothiazine as the donor. Finally, a power conversion efficiency of 8% with chenodeoxycholic acid as the co-absorbant for the DSSC based on Type 1 dyes with triphenylamine is achieved. The results reveal that the donors, the position and number of phenyl unit of the dyes significantly influence the photovoltaic performance of their DSSCs.

Zang, Xu-Feng; Huang, Zu-Sheng; Wu, Han-Lun; Iqbal, Zafar; Wang, Lingyun; Meier, Herbert; Cao, Derong

2014-12-01

214

Monolithic dye laser amplifier  

DOEpatents

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

Kuklo, Thomas C. (Ripon, CA)

1993-01-01

215

Monolithic dye laser amplifier  

DOEpatents

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

Kuklo, T.C.

1993-03-30

216

Solid state dye lasers with scattering feedback  

NASA Astrophysics Data System (ADS)

Over the last decade, significant advances have been made toward the development of practical, tunable solid state dye lasers, which resulted in improved lasing efficiency with reduced dye photodegradation. To achieve this goal, a “chemical” approach was followed, where attention was focused onto the particular dye/host interaction and compatibility, specifically choosing already existing hosts for a given dye, synthesizing new dyes and/or matrices, or chemically modifying existing ones. Nevertheless, this approach was limited by a single fact learnt from the experience: there is no universal matrix which optimizes the efficiency and photostability of all dyes. This limitation could be overcome by following a “physical” approach, where the emission properties of the active medium are tailored by means of physical and structural modifications of the dye host. Following this approach, in this paper recent theoretical and experimental work is reviewed where it is demonstrated that following a simultaneous “physical” and “chemical” approach to tailor the emission properties of the host materials for solid state dye lasers, may lead, under specific circumstances, to the improvement of both the laser efficiency and photostability. In particular, it is demonstrated that optical scattering is not always detrimental either to conventional bulk lasers (laser rods or colloidal suspensions) or to integrated devices, but may give place, on the contrary, to dramatic improvements in the laser operation of organic (hybrid) laser rods, and to alternative ways of obtaining laser light from integrated devices based on the phenomenon of coherent random lasing, where feedback is provided by light scattering in an appropriate medium, without the need to manufacture complex periodic structures in the substrate. The processing and pumping flexibility of these materials, together with their low cost and capability of efficient emission across the whole visible spectrum makes them very attractive for the fabrication and development of coherent light sources suitable for integration in optoelectronic and disposable spectroscopic and sensing devices.

Costela, A.; Cerdán, L.; García-Moreno, I.

2013-11-01

217

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

E-print Network

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

Mohammadi, Narges

2014-01-01

218

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...

219

Dyeing Effects Of Bifunctional Reactive Dyes On Knitted Cotton Fabrics  

Microsoft Academic Search

Several new bifunctional reactive dyes of the Sumifix Supra range that carry monochlorotriazine and sulphato ethyl sulphone reactive systems were developed and their dyeing perfor- mance studied. Suitable characteristic properties and fastness properties were examined over the knitted cotton fab- rics. The dyes were characterized by spectral data and elemental analysis. The dyes structures were established by preparing the coupling

M. M. Dalal; K. R. Desai

1996-01-01

220

Synthesis and photocatalytic activities of CdS/TiO2 nanoparticles supported on carbon nanofibers for high efficient adsorption and simultaneous decomposition of organic dyes.  

PubMed

CdS/TiO2 NPs-decorated carbon nanofibers were prepared by a simple electrospinning method followed by the calcination under argon atmosphere. As-synthesized nanocomposites exhibited a strong photocatalytic activity for decomposition of methylene blue (MB), reactive black 5, and reactive orange 16 under visible light radiation for many successive cycles. Moreover, in the dark, the carbon content revealed very good adsorption behavior as 95% of the dye was removed within 5min, however less adsorption capacity was observed upon successive cycles. Therefore, the enhanced photocatalytic performance for the introduced nanofibers might be attributed to the adsorption characteristic of carbon nanofiber and the known photocatalytic activities of the TiO2 and CdS photocatalysts. PMID:25181331

Pant, Bishweshwar; Barakat, Nasser A M; Pant, Hem Raj; Park, Mira; Saud, Prem Singh; Kim, Jong-Wan; Kim, Hak-Yong

2014-11-15

221

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

PubMed

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

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

2014-04-14

222

Quirks of dye nomenclature. 3. Trypan blue.  

PubMed

Abstract Trypan blue is colorant from the 19(th) century that has an association with Africa as a chemotherapeutic agent against protozoan (Trypanosomal) infections, which cause sleeping sickness. The dye still is used for staining biopsies, living cells and organisms, and it also has been used as a colorant for textiles. PMID:24867494

Cooksey, Cj

2014-11-01

223

Indanthrone dye revisited after sixty years.  

PubMed

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 (), 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

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

2014-09-01

224

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

NASA Astrophysics Data System (ADS)

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

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

2010-09-01

225

Unexpected radiation hazard in dyes of textiles.  

PubMed

Textile dyes are among the most problematic pollutants because of their toxicity on several organisms and ecosystems. Many of the chemicals used in the textile industry may represent some health concerns. The determination of the radioactivity in textile dyes is therefore very important for both human health and environment. The study was designated to determine, for the first time, the values of (238)U, (232)Th and (40)K in nine different dyes employed in the textile industry using gamma spectrometry with a Hyper Pure Germanium (HPGe) detector. The mean activity concentrations of (238)U, (232)Th and (40)K were 29.37?±?4.48, 1.15?±?0.13 and 565?±?4 Bq/kg, respectively. The calculated radium equivalents for all samples were lower than the maximum admissible value (370 Bq/kg). The absorbed dose rates due to the natural radioactivity of the investigated samples ranged from 2.94?±?0.05 to 166?±?3 nGy/h. So, the absorbed dose rates for all samples of textile dyes were lower than the international recommended value (55 nGy/h) except the yellow dye (166?±?3 nGy/h), which recorded a significant radiological hazard. The external hazard index was also calculated. Conclusively, the results have indicated that the textile dyes may possess a measurable amount of radioactivity that should be taken into account. Therefore, safety rules and precautions should be applied for dyes used in the textile industry and for people working in this field. PMID:25322918

Abdel Ghany, Hayam A; Ibrahim, Eman M

2014-12-01

226

Molecular Models of Dyes  

NSDL National Science Digital Library

The paper on the synthesis of several dyes by James V. McCullagh and Kelly A. Daggett (1) provides us with the JCE Featured Molecules for this month. The authors mention various applications of these dyes, ranging from commercial dyeing to techniques for determining the course of complex biochemical processes. One of the reaction products, rhodamine B, is a member of a family of molecules that are widely used as tunable laser dyes. In this application, the rhodamines are most commonly encountered in a cationic form, rather than in the neutral form shown in the paper. In the cations, the carboxyl group is no longer part of a ring system. Several different members of the rhodamine family are included in the molecule collection because substituents have a marked effect on the effective lasing range of a given dye. Additionally, the solvent and the excitation source also influence the lasing range (2). Students can learn more about the relationship between structure, absorption and emission properties, and lasing ranges of various dyes by consulting ref 2 and from PhotochemCAD, Jonathan Lindsey's free application (3).

227

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

SciTech Connect

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

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

2011-09-22

228

Nanowire dye-sensitized solar cells  

Microsoft Academic Search

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

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

2005-01-01

229

Dye Application, Manufacture of Dye Intermediates and Dyes  

NASA Astrophysics Data System (ADS)

It is difficult if not impossible to determine when mankind first systematically applied color to a textile substrate. The first colored fabrics were probably nonwoven felts painted in imitation of animal skins. The first dyeings were probably actually little more than stains from the juice of berries. Ancient Greek writers described painted fabrics worn by the tribes of Asia Minor. But just where did the ancient craft have its origins? Was there one original birthplace or were there a number of simultaneous beginnings around the world?

Freeman, H. S.; Mock, G. N.

230

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

PubMed

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

Trupkin, S; Levin, L; Forchiassin, F; Viale, A

2003-12-01

231

Thermally stable water insoluble azo-azomethine dyes: Synthesis, characterization and solvatochromic properties  

NASA Astrophysics Data System (ADS)

Six new water insoluble azo-azomethine dyes have been synthesized via condensation reaction of ?,?'-bis(o-aminophenylthio)-1,2-xylene with substituted azo-coupled salicylaldehyde. The condensation reaction provides the expected bis-iminated azo-azomethine dyes in good yields, ranging from 59% to 90%. The dyes have been characterized by IR, UV-Vis and 1H NMR spectroscopic methods as well as elemental analysis. The thermal behavior of the prepared dyes has been determined using thermogravimetry technique. Furthermore, the effect of various organic solvents with different polarities on the UV-Vis spectra of the dyes has been also studied.

Khanmohammadi, Hamid; Rezaeian, Khatereh

2012-11-01

232

Capturing the Potential of Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells are a continually developing type of low-cost solar cells that have commercial efficiency around 6-10%. The proposed research here will be focusing on the photo-bleaching and improving techniques for electron transport. Nature has given us a goal to reach towards with proven techniques for converting light into energy with around 30-40% efficiency, however, chlorophyll, the light absorber in plants, is expensive and it is not practical to make solar cells with only chlorophyll as the absorber. One such alternative to chlorophyll is phthalocyanines which is a common industrial dye used in many applications. This dye has a common similar ring without the long phytol chain that chlorophyll has. Previous research has shown that encapsulating organic dyes can magnify the properties of dye from the increased concentration with a possible benefit of stabilizing the dye allowing it to slow down the photo bleaching significantly. Likewise, such encapsulation may help with thermal stability since many dye-sensitized solar cells require a liquid or gel solution that is sensitive to thermal expansion. Many researchers are also finding new ways to encapsulate the dyes or dope the p-n layers with nano and meso tubes to help with electron transport or build the p-n layers right in the tubes. This allows for countless layers and an overall more efficient design.

Benson, James

2010-10-01

233

Lucifer dyes-highly fluorescent dyes for biological tracing  

Microsoft Academic Search

Lucifer dyes are intensely fluorescent 4-aminonaphthalimides which are readily visible in living cells at concentrations and levels of illumination at which they are nontoxic. Because of their low molecular weight they frequently pass from one cell to another; this widespread phenomenon, termed dye-coupling, is thought to reveal functional relationships between cells. Lucifer dyes can also be used for ultrastructural tracing

Walter W. Stewart

1981-01-01

234

Water soluble laser dyes  

DOEpatents

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

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

1998-01-01

235

Water soluble laser dyes  

DOEpatents

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.

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

1998-08-11

236

Excimer Pumped Pulsed Tunable Dye Laser  

NASA Astrophysics Data System (ADS)

It has been recently shown and reported for the first time at this meeting, that Excimer pumping of a single-mode, short-cavity, grazing-incidence, longitudinally-pumped pulsed dye laser is feasible. In this paper the key concepts upon which this latest development is based are presented and are in a somewhat unusual form. This manuscript describes five specific dye laser examples. The five examples represent a progression from the simplest type of dye laser to the single-mode version mentioned above. The examples thus serve as a tutorial introduction to potential users of dye lasers. The article is organized into five sections or STEPS, each of which describes a different pulsed dye laser. Since the subtle points about dye lasers are best appreciated only after one actually attempts to build a working model, a PROCEDURES category is included in which details about the construction of the particular form of laser are given. As one reads through this category, think of it as looking over the shoulder of the laser builder. The NOTES category which follows is a brief but essential discussion explaining why various components and procedures are used, as well as how laser performance specifications are obtained. This subsection can he viewed as a discussion with the laser builder concerning the reasons for specific actions and choices made in the assembly of the example laser. The last category contains COMMENTS which provide additional related information pertaining to the example laser that goes beyond the earlier annotated discussion. If you like, these are the narrator's comments. At the end of the article, after the five sequential forms of the laser have been presented, there is a brief summation.

Littman, Michael G.

1988-06-01

237

Dye filled security seal  

DOEpatents

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

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

1982-04-27

238

Synthetic dye decolourization, textile dye and paper industrial effluent treatment using white rot fungi Lentines edodes  

Microsoft Academic Search

The laccase producing fungi Lentines edodes was screened for laccase production using various indicator compounds like guaiacol, tannic acid and the polymeric dyes such as Remazol brilliant blue R and Poly R-478. The organism Lentines edodes that produce laccase was cultivated on basal medium. Potato dextrose agar medium (PDA) and malt extract agar medium (MEA) were used for the first

S. Shanmugam; P. Rajasekaran; Joseph V. Thanikalb

239

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

PubMed

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

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

2014-08-01

240

Removal of organic dye by air and macroporous ZnO/MoO3/SiO2 hybrid under room conditions  

NASA Astrophysics Data System (ADS)

A new macroporous ZnO/MoO3/SiO2 hybrid was synthesized by a method involving sol-gel technology and biomimetic synthesis. It was characterized by Elemental analysis, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS) and scanning electron microscopy (SEM). Chemical degradation of 0.3 g/L Safranin T (ST) by air oxidation over macroporous ZnO/MoO3/SiO2 hybrid was studied. It was found that the decolorization efficiency and the chemical oxygen demand (COD) removal of ST reached above 95.3% and 93.2%, respectively, within 25 min at room temperature and atmospheric pressure. And the organic pollutant was mineralized to simple inorganic species such as HCO3-, Cl- and NO3-, while the total organic carbon (TOC) decreased 95.4%. The structure and morphology of the catalyst were still stable after six cycling runs and the leaching test showed negligible leaching effect.

Yuan, Mengjia; Wang, Shengtian; Wang, Xiaohong; Zhao, Lingling; Hao, Tianhong

2011-07-01

241

[Allergy to dyes in stockings].  

PubMed

Skin allergies caused by the wearing of stockings and hose have received little attention. Findings in patients of an allergy department, enquiries at stocking counters of stores and recent publications indicate, however, that probably many more persons have an allergy to stocking dyes than is generally thought. Skin tests with isolated stocking dyes indicate that azo dye dispersion yellow 3, dispersion orange 3 and dispersion red 1 are the most important contact allergens. They were demonstrated in 18-21 of the 23 hose examined. In textile materials, azo dye dispersion blue 124 is predominant among allergens. Cross-reactions may occur to other dispersion azo dyes, used in cosmetics, textiles, toiletries and hygenic articles, permitted food additives and hair dyes. It is suggested that in persons who have dye allergy or intolerance, decolouration followed by colouring with natural colours be undertaken. PMID:6479046

Hausen, B M; Schulz, K H

1984-09-28

242

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

PubMed

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

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

2011-12-28

243

Painting With Natural Dyes  

NSDL National Science Digital Library

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

Barbara Arrowtop (Heart Butte School)

1999-07-01

244

Microwave assisted dyeing of polyester fabrics with disperse dyes.  

PubMed

Dyeing of polyester fabrics with thienobenzochromene disperse dyes under conventional and microwave heating conditions was studied in order to determine whether microwave heating could be used to enhance the dyeability of polyester fabrics. Fastness properties of the dyed samples were measured. All samples dyed with or without microwave heating displayed excellent washing and perspiration fastness. The biological activities of the synthesized dyes against Gram positive bacteria, Gram negative bacteria, yeast and fungus were also evaluated. PMID:24022764

Al-Mousawi, Saleh Mohammed; El-Apasery, Morsy Ahmed; Elnagdi, Mohamed Hilmy

2013-01-01

245

Dye laser tuner  

SciTech Connect

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

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

1980-11-11

246

Organization.  

ERIC Educational Resources Information Center

This theme issue on organization provides an annotated listing of Web sites, CD-ROMs and software, videos, books, and other resources related to organization to be used with K-8 students. Sidebars discuss being organized to be a good student, organizational identities, and organizing an election. Suggests student activities relating to…

Online-Offline, 1999

1999-01-01

247

Molecular cloning and expression of glutathione S-transferases involved in propargite resistance of the carmine spider mite, Tetranychus cinnabarinus (Boisduval).  

PubMed

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

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

248

Fine tuning of fluorene-based dye structures for high-efficiency p-type dye-sensitized solar cells.  

PubMed

We report on an experimental study of three organic push-pull dyes (coded as zzx-op1, zzx-op1-2, and zzx-op1-3) featuring one, two, and three fluorene units as spacers between donors and acceptors for p-type dye-sensitized solar cells (p-DSSC). The results show increasing the number of spacer units leads to obvious increases of the absorption intensity between 300 nm and 420 nm, a subtle increase in hole driving force, and almost the same hole injection rate from dyes to NiO nanoparticles. Under optimized conditions, the zzx-op1-2 dye with two fluorene spacer units outperforms other two dyes in p-DSSC. It exhibits an unprecedented photocurrent density of 7.57 mA cm(-2) under full sun illumination (simulated AM 1.5G light illumination, 100 mW cm(-2)) when the I(-)/I3(-) redox couple and commercial NiO nanoparticles were used as an electrolyte and a semiconductor, respectively. The cells exhibited excellent long-term stability. Theoretical calculations, impedance spectroscopy, and transient photovoltage decay measurements reveal that the zzx-op1-2 exhibits lower photocurrent losses, longer hole lifetime, and higher photogenerated hole density than zzx-op1 and zzx-op1-3. A dye packing model was proposed to reveal the impact of dye aggregation on the overall photovoltaic performance. Our results suggest that the structural engineering of organic dyes is important to enhance the photovoltaic performance of p-DSSC. PMID:24918263

Liu, Zonghao; Li, Wenhui; Topa, Sanjida; Xu, Xiaobao; Zeng, Xianwei; Zhao, Zhixin; Wang, Mingkui; Chen, Wei; Wang, Feng; Cheng, Yi-Bing; He, Hongshan

2014-07-01

249

Investigation of red natural dyes used in historical objects by HPLC-DAD-MS.  

PubMed

High performance liquid chromatography (HPLC) with UV-Vis Diode Array Detection (DAD) and electrospray mass spectrometric (ESI-MS) method was utilized for the identification of coloring components of madder, Armenian and Mexican cochineal, lac dye, brazilwood, safflower and dragon blood--probably the most important red natural dyestuffs found in objects of the cultural heritage. UV-Vis detection limits in the range of 0.2-0.6 ng for carminic acid, alizarin and purpurin were achieved using a gradient elution of H2O-0.01% TFA and CH3CN-0.01% TFA. ESI mass spectrometer was also used, as a supportive detection method to the standard DAD, for further analysis of the tested materials, with the ability to analyze dyestuffs as small as one milligram. The presence of madder was revealed in two historical (Hellenistic and Roman period) samples, found in the Mediterranean area, by identifying purpurin in both of them. Munjistin was also identified in one of the samples (Hellenistic period) while alizarin was not detected, raising questions regarding the exact madder type, utilized in the historical samples. PMID:16736555

Karapanagiotis, Ioannis; Chryssoulakis, Yannis

2006-01-01

250

Grape stalks as substrate for white rot fungi, lignocellulolytic enzyme production and dye decolorization.  

PubMed

The aim of this work was to evaluate the potential of grape stalks, an agroindustrial waste, for growth and lignocellulolytic enzyme production via solid-state fermentation, using the following three white rot fungi: Trametes trogii, Stereum hirsutum and Coriolus antarcticus. The decolorization of several dyes by the above mentioned cultures was also investigated. Similar values of dry weight loss of the substrate were measured after 60 days (33-43 %). C. antarcticus produced the highest laccase and Mn-peroxidase activities (33.0 and 1.6 U/g dry solid). The maximum endoglucanase production was measured in S. hirsutum cultures (10.4 U/g), while the endoxylanase peak corresponded to T. trogii (14.6 U/g). The C. antarcticus/grape stalk system seems potentially competitive in bioremediation of textile processing effluents, attaining percentages of decolorization of 93, 86, 82, 82, 77, and 58% for indigo carmine, malachite green, azure B, remazol brilliant blue R, crystal violet and xylidine, respectively, in 5 h. PMID:22997770

Levin, Laura; Diorio, Luis; Grassi, Emanuel; Forchiassin, Flavia

2012-01-01

251

Near Infrared Dyes as Lifetime Solvatochromic Probes for Micropolarity Measurements of Biological Systems  

Microsoft Academic Search

The polarity of biological mediums controls a host of physiological processes such as digestion, signaling, transportation, metabolism, and excretion. With the recent widespread use of near-infrared (NIR) fluorescent dyes for biological imaging of cells and living organisms, reporting medium polarity with these dyes would provide invaluable functional information in addition to conventional optical imaging parameters. Here, we report a new

Mikhail Y. Berezin; Hyeran Lee; Walter Akers; Samuel Achilefu

2007-01-01

252

Synthesis and spectroscopic characterization of Kiton Red620 dye doped silica gel rods  

Microsoft Academic Search

The work was carried out to achieve two different but interdependent objectives; one to synthesis a transparent silica matrix with enough strength and thermal stability, by sol–gel technique, to host an organic dye molecule without quenching its fluorescence and two to find the probability if the said material is suitable for the construction of solid state dye lasers. Crack-free transparent

Fozia Z. Haque; Vazid Ali; M. Husain

253

Decolorization and Detoxification of Textile Dyes with a Laccase from Trametes hirsuta  

Microsoft Academic Search

Trametes hirsuta and a purified laccase from this organism were able to degrade triarylmethane, indigoid, azo, and anthraquinonic dyes. Initial decolorization velocities depended on the substituents on the phenolic rings of the dyes. Immobilization of the T. hirsuta laccase on alumina enhanced the thermal stabilities of the enzyme and its tolerance against some enzyme inhibitors, such as halides, copper chelators,

ELIAS ABADULLA; TZANKO TZANOV; SILGIA COSTA; KARL-HEINZ ROBRA; ARTUR CAVACO-PAULO; GEORG M. GUBITZ

2000-01-01

254

Electrochemical oxidation of a textile dye wastewater using a Pt\\/Ti electrode  

Microsoft Academic Search

Textile dye wastewater (TDW) from a reactive azo dyeing process was treated by an electrochemical oxidation method using Ti\\/Pt as anode and stainless steel 304 as cathode. Due to the strong oxidizing potential of the chemicals produced (chlorine, oxygen, hydroxyl radicals and other oxidants) when the wastewater was passed through the electrolytic cell the organic pollutants were oxidized to carbon

A. G Vlyssides; M Loizidou; P. K Karlis; A. A Zorpas; D Papaioannou

1999-01-01

255

Spectroscopic and photoelectrochemical studies of metal-free dyes for applications in dye-sensitized solar cells  

NASA Astrophysics Data System (ADS)

In this dissertation, we present a series of novel chalcogenorhodamine dyes bearing phosphonic acids and carboxylic acids for sensitizers of nanocrystalline TiO2 in dye-sensitized solar cells (DSCs). We studied the effect of surface-attachment functionality and aggregation on the persistence, electron transfer reactivity, and overall photoelectrochemical performance of the dyes on TiO2 for DSCs. The dyes were constructed around a 3,6-bis(dimethylamino)chalcogenoxanthylium core and varied in the 9-substituent: 5-carboxythien-2-yl in dyes 1-E (E = O, Se), 2-carboxythien-3-yl in dyes 2-E (E = Se), 5-phosphonothien-2-yl in dyes 3-E (E = O, Se), 4-carboxyphenyl in dyes 4-E (E = O, S), and 4-phosphonophenyl in dyes 5-E (E = O, Se). Monolayers of 1-E, 3-E, 4-E, and 5-E on nanocrystalline TiO2 films consisted of both H-aggregated and non-aggregated dyes, whereas 2-E underwent little or no aggregation upon adsorption. With the exception of 2-E, surface coverages of dyes and the extent of H-aggregation varied minimally with surface-attachment functionality, structure of the 9-aryl group, and identity of the chalcogen heteroatom. Carboxylic acid-functionalized dyes 1-E and 4-E desorbed rapidly and completely from TiO2 into acidified CH3CN, but phosphonic acid-functionalized dyes 3-E and 5-E persisted on TiO2 for days. We used transient absorption spectroscopy to characterize excited-state electron injection from a 1-Se, 2-Se, and 3-Se to TiO2. Injection of electrons from photoexcited dyes into TiO2 yielded the dication radical (1-Se +, 2-Se+, and 3-Se +) and an associated transient absorption at wavelengths shorter than 540 nm, the amplitude of which was proportional to the quantum yield of electron injection (Qinj). Our data reveal the Qinj for H-aggregated 1-Se was approximately 2-fold greater than Q inj for non-aggregated 1-Se and approximately 3-fold greater than Qinj for non-aggregated 2-Se. Additionally, the Qinj from H-aggregated 3-Se was (2.0 +/- 1.3)-fold greater than from monomeric 3-Se. Therefore, H-aggregation increased the efficiencies of both light-harvesting and electron injection. Comparison of the analogous carboxylic acid-functionalized dye (1-Se) and phosphonic acid-functionalized dye (3-Se) revealed that Q inj via the carboxylate linkage was (2.3 +/- 1.1)-fold greater than via the phosphonate linkage. Thus, electron-injection reactivity is sensitive to both the aggregation state and the surface-anchoring mode of these chalcogenorhodamine dyes. Short-circuit photocurrent action spectra of DSCs corresponded closely to absorptance spectra of dye-functionalized films; thus, H-aggregation did not decrease the electron-injection yield or charge-collection efficiency. Maximum monochromatic incident photon-to-current efficiencies (IPCEs) of DSCs ranged from 53% to 95% and were slightly higher for carboxylic acid-functionalized dyes 1-E and 4-E. The photoelectrochemical performance (under monochromatic or white-light illumination) of 1-E and 4-E decayed significantly within 20-80 min of assembly of DSCs, due primarily to desorption of the dyes. In contrast, the performance of phosphonic acid-functionalized dyes (3-E and 5-E) remained stable or improved slightly on similar time scales. Power-conversion efficiencies of DSCs under white-light illumination were low (<1%), suggesting that dye regeneration was inefficient at high light intensities. Preliminary transient photovoltage results support this proposition. Our findings suggest that controlled aggregation of organic dyes may represent an attractive strategy for improving the global energy-conversion efficiencies of organic dye-sensitized solar cells and photocatalysts. In addition, replacing carboxylic acids with phosphonic acids increased the inertness of chalcogenorhodamine-TiO2 interfaces without greatly impacting aggregation of dyes or the interfacial electron-transfer reactivity. The decrease of Qinj for phosphonic acid-bearing dyes is offset by its enhanced stability and persistence on TiO2, rendering the phosphonic acid-functionalized and H-aggregating dyes

Mulhern, Kacie Ryan

256

Decolorization Of Textile Dye Solutions  

Microsoft Academic Search

Results are presented on the use of ozone to decolorize textile dye solutions. The results describe the rates of reaction and the stoichiometry for the use of ozone to decolorize a simulated wastewater containing a bisazo acid dye (Acid Red 158). These rates of reaction are not sensitive to pH and are only mildly affected by temperature. The effects of

Julie Carrière; J. Peter Jones; Arthur D. Broadbent

1993-01-01

257

Optofluidic Distributed Feedback Dye Lasers  

Microsoft Academic Search

We review our recent work on poly(dimethylsiloxane) (PDMS)-based optofluidic dye lasers using a guided wave distributed feedback (DFB) cavity. We show experimental results of single-mode operation, an integrated laser array, multiple color dye lasing, mechanical and fluidic tuning, and monolithic integration with microfluidic circuits. Potential applications and future directions are discussed

Zhenyu Li; Demetri Psaltis

2007-01-01

258

Optofluidic ring resonator dye lasers  

Microsoft Academic Search

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

Yuze Sun; Jonathan D. Suter; Xudong Fan

2010-01-01

259

Fluorometric procedures for dye tracing  

USGS Publications Warehouse

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

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

1984-01-01

260

Light-induced rearrangements of chemisorbed dyes on anatase(101).  

PubMed

Photoinduced molecular rearrangements are important in daily events essential for life such as visual perception and photo-protection of light harvesting complexes in plants. In this study we demonstrate that similar photoarrangements appear in an analogous technological application where the device performance is controlled by chromophores in sensitized anatase TiO(2), one of the main components for light-harvesting in dye-sensitized solar cells (DSC). STM reveals that illumination leads to distortions of organic dyes containing conjugated backbones and of cis-bis(isothiocyanate)-bis-(2,2'-bipyridyl-4,4'-dicarboxylate)ruthenium(II)-bis(tetrabutylammonium), known as N719. The dyes were adsorbed in a closed-packed mode on an anatase(101) single crystal surface and imaged in the dark and under white light illumination in an ultra-high vacuum (UHV). STM images of N719 clearly suggest rearrangements caused by rotation of the dye. Conversely, organic dyes rearrange by photoisomerization depending on the number of double bonds, their position in the molecular structure and on the ligand modifications. PMID:22785456

Zuleta, Marcelo; Edvinsson, Tomas; Yu, Shun; Ahmadi, Sareh; Boschloo, Gerrit; Göthelid, Mats; Hagfeldt, Anders

2012-08-14

261

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

E-print Network

High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells Brian E soluble energy relay dyes with high molar extinction coefficients. KEYWORDS Solar cell, energy transfer, dye-sensitized dolar cell, energy relay dye, titania L ong range energy transfer has recently been

McGehee, Michael

262

Never say dye  

PubMed Central

Recent years have seen a remarkable increase in the number of publications dealing with the application of epifluorescence microscopy in cell biology. This can be widely attributed to the development of state-of-the-art image processing programs, as well as the development of new reagents/probes, which allow the labeling of most cell structures, organelles and metabolites with high specificity. However, the use of a specific fluorescent dye, 3,3?-dihexyloxacarbocyanine iodide (DiOC6), has been recently revisited and several new application potentials have emerged. The goal of this mini-review is to provide an up-to-date overview of the multiple roles of this multifaceted probe. PMID:22476459

2012-01-01

263

Single-beam Z-scan measurement of the third-order optical nonlinearities of triarylmethane dyes  

NASA Astrophysics Data System (ADS)

Solid-state dye-doped polymers are an attractive alternative to the conventional liquid-dye solutions. The search for new materials which have potential application in optoelectronic devices has lead us to probe the organic dyes. The solid state being a better medium when compared to a liquid medium has lead to the incorporation of dyes in the polymer matrix. The study of nonlinear characteristics of dyes in polymeric media is essential for developing such potential application devices. In this paper, the third-order nonlinear optical properties of three dyes from the Triarylmethane family were measured in 1-Butanol and in dye-doped polymer films by the Z-scan technique using a cw diode-pumped Nd:YAG laser at 532 nm. The Z-scan technique has also been used to present the observation of a nonlinear refractive index resulting from the photochromism of one of the dyes. These materials exhibit a large negative optical nonlinearity resulting due to the thermal effect. The relative contributions from the nonlinear absorption (NLA) and nonlinear refraction (NLR) are dependent on the chemical structure and linear absorption of the dyes. The dyes exhibited a nonlinear refractive coefficient n 2, a nonlinear absorption coefficient ?, and susceptibility x(3) on the order of 10-8 cm2/W, 10-4 cm/W, and 10-6 esu, respectively, in both liquid and solid media. The results show that these dyes have potential applications in nonlinear optics.

Vinitha, G.; Ramalingam, A.

2008-10-01

264

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

PubMed Central

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

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

2013-01-01

265

Photovoltaic performance and long-term stability of quasi-solid-state fluoranthene dyes-sensitized solar cells  

Microsoft Academic Search

Two new fluoranthene-based organic dye sensitizers (I and II), in which 7, 12-diphenylbenzo[k]fluoranthene moiety is acted as electron donor, thiophene and phenylethynyl units as electron spacers and carboxylic acid as electron acceptor were successfully applied in quasi-solid-state dye-sensitized solar cells. The quasi-solid-state DSSCs based on the dye I showed the better photovoltaic performance: a maximum monochromatic incident photon-to-current conversion efficiency

Wenjun Wu; Jing Li; Fuling Guo; Lei Zhang; Yitao Long; Jianli Hua

2010-01-01

266

Photoelectrochemical properties of the CT1 dye: A DFT study  

NASA Astrophysics Data System (ADS)

We report a comprehensive computational study on the electronic and optical properties of a hemi-squaraine organic dye recently proposed for Dye Sensitized Solar Cells (DSSCs) applications. Ground and excited state properties have been computed within DFT and TD-DFT approaches, respectively. Results from 10 different functionals ranging from pure GGA (mPW91 and PBE), to global hybrids (B3LYP, PBE0, mPW1K and M05-2X) and range separated hybrids (?-B97X, LC-?PBE, CAM-B3LYP and HSE06) have been analyzed and compared to available experimental data. Aggregation effects on the electrochemical and optical properties of the dye have been also analyzed.

Camino, Bruno; De La Pierre, Marco; Ferrari, Anna Maria

2013-08-01

267

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

DOEpatents

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

Davin, James (Gilroy, CA)

1992-01-01

268

Enhanced brightness and photostability of cyanine dyes by supramolecular containment  

E-print Network

Ultrasensitive detection and real-time monitoring of biological processes can benefit significantly from the improved brightness and photostability of the popular organic dyes such as cyanines. Here, using a model cyanine dye, Cy3, we demonstrate that brightness and photostability of the dye is significantly altered when trapped in a molecular container, e.g. cucurbit[n]urils (CB[n]) and cyclodextrins (CD).Through computational modeling, we predicted that Cy3 forms a stable inclusion complex with three different hosts, CB[7], beta-CD, and methyl-beta-CD, which was further confirmed by single-molecule diffusion measurements using fluorescence correlation spectroscopy. The effect of supramolecular encapsulation on Cy3 photophysical properties was found to be highly host-specific. Up to three-fold increase in brightness of Cy3 was observed when the dye was trapped in methyl-beta-CD, due to an increase in both dye absorption and quantum yield. Steady-state and time-resolved spectroscopy of the various complexes r...

Muddana, Hari S; Sen, Ayusman; Butler, Peter J

2014-01-01

269

Direct identification of early synthetic dyes: FT-Raman study of the illustrated broadside prints of José Gaudalupe Posada (1852-1913)  

NASA Astrophysics Data System (ADS)

Fourier Transform (FT)-Raman spectroscopy was used for the non-invasive, direct identification of colorants used to dye historical printed papers, overcoming obstacles such as low concentration of the dye, faded colors and fluorescence interference of the aged paper substrate. Based on a newly created FT-Raman reference database of 20 widely used dyes in the 19th century paper industry, the detectability of these dyes on aged biomaterials was determined by studying dyed paper samples from contemporary dye manuals, and identifying diagnostic peaks detectable on those substrates. Lastly, the method was applied to analyze the colorants used to dye the papers of a group of prints illustrated by the influential Mexico City artist José Guadalupe Posada, active 1876-1913. Unambiguous identification of the synthetic organic colorants Malachite Green (a triarylmethane dye), Orange II and Metanil Yellow (two acid monoazo dyes), Cotton Scarlet (an acid diazo dye), Phloxine (a xanthene dye) and Victoria Blue (a triarylmethane dye) in several of Posada’s prints challenged previous art-historical assumptions that these artworks were colored with natural dyes. The acquired knowledge has important conservation implications given that aniline dyes are sensitive to light and to aqueous treatments otherwise commonly carried out on works of art on paper.

Casadio, F.; Mauck, K.; Chefitz, M.; Freeman, R.

2010-09-01

270

A vibrational spectroscopic and principal component analysis of triarylmethane dyes by comparative laboratory and portable instrumentation.  

PubMed

This contribution examines the utility of vibrational spectroscopy by bench and portable Raman/surface enhanced Raman and infrared methods for the investigation of ten early triarlymethane dye powder references and dye solutions applied on paper. The complementary information afforded by the techniques is shown to play a key role in the identification of specific spectral marker ranges to distiguish early synthetic dyes of art-historical interest through the elaboration of an in-house database of modern organic dyes. Chemometric analysis has permitted a separation of data by the discrimination of di-phenyl-naphthalenes and triphenylmethanes (di-amino and tri-amino derivatives). This work serves as a prelude to the validation of a non-invasive working method for in situ characterization of these synthetic dyes through a careful comparison of respective strengths and limitations of each portable technique. PMID:24252295

Doherty, B; Vagnini, M; Dufourmantelle, K; Sgamellotti, A; Brunetti, B; Miliani, C

2014-01-01

271

Decolorization and degradation of reactive dye during the dyed cotton fabric rinsing process.  

PubMed

Dyeing process of textile consumes large quantities of water, which results in huge amounts of colored wastewater. Most of the dye wastewater treating methods focused on the treatment of wastewater after the rinsing process of dyed textile. In this paper, tetraacetylethylenediamine/hydrogen peroxide (TAED/H?O?) active oxidation (AO) system was developed to rinse dyed textile and decolorize the rinsing wastewater simultaneously. The results indicated that the decolorization ratio of the rinse effluent obtained by AO method were in the range of 51.72%-84.15% according to different dyes and the COD value decreased more than 30% compared with that of traditional rinsing process. The decolorization kinetics investigation showed that the decolorization of dyes during AO rinsing process followed the law of pseudo-first order kinetics. The result of UV-Vis and UPLC-MS analysis demonstrated that the dye was degraded into colorless organic molecular fragments and partly mineralized during the AO rinsing process. PMID:20729577

Luo, Deng-Hong; Zheng, Qing-Kang; Chen, Sheng; Liu, Qing-Shu; Wang, Xiu-Xing; Guan, Yu; Pu, Zong-Yao

2010-01-01

272

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

PubMed

Simultaneous dyeing and antibacterial finishing for cotton fabric using a new antibacterial reactive dye having a modified chemical structure to the commercial reactive dye CI Reactive Red 198 were studied. This modification was carried out by replacing metanilic acid in the commercial dye with 4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (sulfadimidine). Optimum exhaustion and fixation values were achieved at 60 g/l sodium sulphate and 20 g/l sodium carbonate for both dyes. The modified dye exhibited higher substantivity, exhaustion and fixation efficiency compared to the commercial dye. Antibacterial activities of the dyed samples at different concentrations of both dyes were studied against gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria. The cotton dyed with the modified dye shows higher antibacterial efficacy compared to the dyed cotton fabric using the commercial dye, especially on gram negative (E. coli) bacteria. All the reactive dyeings also exhibited high fastness properties. PMID:23769529

Farouk, R; Gaffer, H E

2013-08-14

273

Novel fluoranthene dyes for efficient dye-sensitized solar cells  

Microsoft Academic Search

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

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

2009-01-01

274

Sea dye marker provides visibility for 20 hours  

NASA Technical Reports Server (NTRS)

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

De Laat, F.

1966-01-01

275

Modeling materials and processes in dye-sensitized solar cells: understanding the mechanism, improving the efficiency.  

PubMed

We present a review of recent first-principles computational modeling studies on dye-sensitized solar cells (DSCs), focusing on the materials and processes modeling aspects which are key to the functioning of this promising class of photovoltaic devices. Crucial to the DSCs functioning is the photoinduced charge separation occurring at the heterointerface(s) between a dye-sensitized nanocrystalline, mesoporous metal oxide electrode and a redox shuttle. Theoretical and computational modeling of isolated cell components (e.g., dye, semiconductor nanoparticles, redox shuttle, etc…) as well as of combined dye/semiconductor/redox shuttle systems can successfully assist the experimental research by providing basic design rules of new sensitizers and a deeper comprehension of the fundamental chemical and physical processes governing the cell functioning and its performances. A computational approach to DSCs modeling can essentially be cast into a stepwise problem, whereby one first needs to simulate accurately the individual DSCs components to move to relevant pair (or higher order) interactions characterizing the device functioning. This information can contribute to enhancing further the target DSCs characteristics, such as temporal stability and optimization of device components. After presenting selected results for isolated dyes, including the computational design of new dyes, and model semiconductors, including realistic nanostructure models, we focus in the remainder of this review on the interaction between dye-sensitizers and semiconductor oxides, covering organic as well as metallorganic dyes. PMID:24682760

Pastore, Mariachiara; De Angelis, Filippo

2014-01-01

276

Textile dye removal from wastewater effluents using bioflocculants produced by indigenous bacterial isolates.  

PubMed

Bioflocculant-producing bacteria were isolated from activated sludge of a wastewater treatment plant located in Durban, South Africa, and identified using standard biochemical tests as well as the analysis of their 16S rRNA gene sequences. The bioflocculants produced by these organisms were ethanol precipitated, purified using 2% (w/v) cetylpyridinium chloride solution and evaluated for removal of wastewater dyes under different pH, temperature and nutritional conditions. Bioflocculants from these indigenous bacteria were very effective for decolourizing the different dyes tested in this study, with a removal rate of up to 97.04%. The decolourization efficiency was largely influenced by the type of dye, pH, temperature, and flocculant concentration. A pH of 7 was found to be optimum for the removal of both whale and mediblue dyes, while the optimum pH for fawn and mixed dye removal was found to be between 9 and 10. Optimum temperature for whale and mediblue dye removal was 35 °C, and that for fawn and mixed dye varied between 40–45 °C and 35–40 °C, respectively. These bacterial bioflocculants may provide an economical and cleaner alternative to replace or supplement present treatment processes for the removal of dyes from wastewater effluents, since they are biodegradable and easily sustainable. PMID:23201644

Buthelezi, Simphiwe P; Olaniran, Ademola O; Pillay, Balakrishna

2012-01-01

277

Investigation of dye regeneration kinetics in sensitized solar cells by scanning electrochemical microscopy.  

PubMed

Sensitizers are responsible for the light harvesting and the charge injection in dye-sensitized solar cells (DSSCs). A fast dye-regeneration process is necessary to obtain highly efficient DSSC devices. Herein, dye-regeneration rates of two DSSC device types, that is, the reduction of immediately formed photo-oxidized sensitizers (ruthenium complex C106TBA and porphyrin LD14, k(ox)') by iodide ions (I(-)) and [Co(bpy)3](2+), and the oxidation of formed photo-reduced sensitizers (organic dye P1, k(re)') by triiodide ions (I3(-)) and the disulfide dimer (T2) are investigated by scanning electrochemical microscopy (SECM). We provide a thorough experimental verification of the feedback mode to compare the kinetics for dye-regeneration by using the above mentioned mediators. The charge recombination at the dye/semiconductor/electrolyte interface is further investigated by SECM. A theoretical model is applied to interpret the current response at the tip under short-circuit conditions, providing important information on factors that govern the dynamics of dye-regeneration onto the dye-sensitized heterojunction. PMID:24729527

Zhang, Bingyan; Xu, Xiaobao; Zhang, Xiaofan; Huang, Dekang; Li, Shaohui; Zhang, Yibo; Zhan, Fang; Deng, Mingzhang; He, Yahui; Chen, Wei; Shen, Yan; Wang, Mingkui

2014-04-14

278

THE EFFECT OF DYES ON THE CALCIFICATION OF HYPERTROPHIC RACHITIC CARTILAGE IN VITRO  

PubMed Central

The calcification of rat hypertrophic cartilage slices in vitro is markedly inhibited by preliminary exposure to metachromatic and other basic dyes. The dyes are effective at 10–3 to 10–4 M in the absence of calcium and phosphate. This inhibition does not occur at the same low dye concentration if calcium and phosphate are present. Neither ion alone is effective in preventing the inhibition. The inhibitory action can be removed by placing slices which have been treated with basic dye in a solution which contains calcium and phosphate ions, plus an acid dye, Orange G. Most acid dyes do not inhibit calcification, except at very high concentrations. Alizarin and quinalizarin are exceptional, and produce marked inhibition at 10–3 M, an effect which is perhaps attributable to the tendency of these dyes to form lakes with calcium. Rachitic cartilage slices which no longer calcify in inorganic phosphate as a result of treatment with basic dyes show normal calcification in the presence of organic phosphate esters. These results are discussed in terms of the possibility that chondroitin sulfate ester participates in normal calcification. PMID:14927802

Miller, Zelma B.; Waldman, Jerome; McLean, Franklin C.

1952-01-01

279

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

PubMed Central

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

2013-01-01

280

Dyeing behavior of low temperature plasma treated wool  

Microsoft Academic Search

In this paper, the effects of low temperature plasma (LTP) treatment on the dyeing properties of the wool fiber were studied.\\u000a The wool fibers were treated with oxygen plasma and three types of dye that commonly used for wool dyeing, namely: (i) acid\\u000a dye, (ii) chrome dye and (iii) reactive dye, were used in the dyeing process. For acid dyeing,

C. W. Kan

2006-01-01

281

Influence of Film Structure and Precursor Composition on Rhodamine B Retention in Dye-Dopped Ormosils  

Microsoft Academic Search

The interplay between the chemical structure of the precursors, internal organization in the end materials and dye retention was investigated for composites (ormosils) doped with rhodamine B. Besides formulations with triethoxysilanes (RTES) only, we synthesized as well organic–inorganic hybrids with addition of titanium isopropoxide (TIP) and maleic anhydride (MA). The organic (R) functionality of RTES was changed from methyl (MeTES),

Violeta I. Uricanu; Dan Donescu; Andrei G. Banu; Sever Serban; Marilena Vasilescu; Mihaela Olteanu; Manuela Dudau

2005-01-01

282

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

E-print Network

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

Smith, Bradley D.

283

Electronic and Optical Properties of Dye-Sensitized TiO2 Interfaces.  

PubMed

Dye-sensitized solar cells (DSCs) represent a promising approach to the direct conversion of sunlight to electrical energy at low cost and high efficiency. DSCs are based on a film of anatase TiO2 nanoparticles covered by adsorbed molecular dyes and immersed in a liquid redox electrolyte. Upon photoexcitation of the chemisorbed dye, electrons are injected into the TiO2 conduction band and can travel across the nanostructured film to reach the counter-electrode, while the oxidized dye is regenerated by the redox electrolyte. In this review we present a summary of recent computational studies of the electronic and optical properties of dye-sensitized TiO2 interfaces, with the aim of providing the basic understanding of the operation principles of DSCs and establishing the conceptual basis for their design and optimization.We start with a discussion of isolated dyes in solution, focusing on the dye's atomic structure, ground and excited state oxidation potentials, and optical absorption spectra. We examine both Ru(II)-polypyridyl complexes and organic "push-pull" dyes with a D-?-A structure, where the donor group (D) is an electron-rich unit, linked through a conjugated linker (?) to the electron-acceptor group (A). We show that a properly calibrated computational approach based on Density Functional Theory (DFT) combined with Time Dependent DFT (TD-DFT) can provide a good description of both the absorption spectra and ground and excited state oxidation potential values of the Ru(II) complexes. On the other hand, organic push-pull dyes are not well described by the standard DFT/TD-DFT approach. For these dyes, an excellent description of the electronic structure in gas phase can be obtained by the many body perturbation theory GW method, which has, however, a much higher computational cost.We next consider interacting dye/semiconductor systems. Key properties are the dye adsorption structure onto the semiconductor, the nature and localization of the dye@semiconductor excited states, and the alignment of ground and excited state energy levels at the dye/semiconductor heterointerface. These properties, along with an estimate of the electronic coupling, constitute the fundamental parameters that determine the electron injection and dye regeneration processes. For metallorganic dyes, standard DFT/TDDFT methods are again found to reproduce accurately most of the relevant electronic and optical properties. For highly conjugated organic dyes, characterized by a high degree of charge transfer excited states, instead, the problems associated to the charge-transfer nature of their excited states extend to their interaction with TiO2 and translate into an erroneous description of the relative energetics of dye/semiconductor excited states. A full description of push-pull organic dyes/semiconductor excited states, which is essential for modeling the key process of electron injection in DSCs, still represents a challenge which should be addressed by next generation DFT or post-DFT methods. PMID:24488437

Pastore, Mariachiara; Selloni, Annabella; Fantacci, Simona; De Angelis, Filippo

2014-01-01

284

Single mode pulsed dye laser oscillator  

DOEpatents

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.

Hackel, Richard P. (Livermore, CA)

1992-01-01

285

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...

286

FATE OF COMMERCIAL DISPERSE DYES IN SEDIMENTS  

EPA Science Inventory

Kinetics of disappearance of seven different disperse dyes were determined in compacted sediments at room temperature. he commercial dyes (in dispersed solid form) were representative of nitroazo, anthraquinone, and quinoline structures that are widely used. eaction rates were fo...

287

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

Microsoft Academic Search

Azo dyes represent the largest class of dyes in use today. Current environmental concern with these dyes revolves around the potential carcinogenic health risk presented by these dyes or their intermediate biodegradation products when exposed to microflora in the human digestive tract. These dyes may build up in the environment, since many wastewater treatment plants allow these dyes to pass

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

1994-01-01

288

Ligninase-catalysed decolorization of synthetic dyes  

Microsoft Academic Search

Many synthetic dyes in industrial wastewaters are resistant to degradation in conventional biological treatment process. Decolorization of eight synthetic dyes including azo, anthraquinone, metal complex and indigo were examined in white-rot fungal cultures and by fungal peroxidase-catalysed oxidation. The dyes were not decolorized by manganese-dependent peroxidase (MnP) while above 80% color was removed by ligninase-catalysed oxidation. Dye decolorization rate increased

Lawrence Young; Jian Yu

1997-01-01

289

Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of 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.

Davin, James (Gilroy, CA)

1992-01-01

290

Laser action of dyes in gelatin  

Microsoft Academic Search

High-gain directional stimulated emission has been observed for a number of dyes in gelatin with pumping by a nitrogen laser or a liquid dye laser. For some dyes the gel is made with water and gelatin; for others a detergent must be added or glycerin used instead of water.

T. Hansch; M. Pernier; A. Schawlow

1971-01-01

291

Microbial decolourisation and degradation of textile dyes  

Microsoft Academic Search

Dyes and dyestuffs find use in a wide range of industries but are of primary importance to textile manufacturing. Wastewater from the textile industry can contain a variety of polluting substances including dyes. Increasingly, environmental legislation is being imposed to control the release of dyes, in particular azo-based compounds, into the environment. The ability of microorganisms to decolourise and metabolise

G. McMullan; C. Meehan; A. Conneely; N. Kirby; T. Robinson; P. Nigam; I. M. Banat; R. Marchant; W. F. Smyth

2001-01-01

292

Quirks of dye nomenclature. 1. Evans blue.  

PubMed

The history, origin, identity, chemistry and use of Evans blue dye are described along with the first application to staining by Herbert McLean Evans in 1914. In the 1930s, the dye was marketed under the name, Evans blue dye, which was profoundly more acceptable than the ponderous chemical name. PMID:23957706

Cooksey, C J

2014-02-01

293

Laccase-catalyzed decolorization of synthetic dyes  

Microsoft Academic Search

Commercial dyes are not uniformly susceptible to microbial attack in conventional aerobic treatment because of their unique and stable chemical structures. Three synthetic dyes with typical chromophores (anthraquinone, azo and indigo) were decolorized by a white-rot fungus Trametes versicolor. The responsible enzyme for dye decomposition was laccase, an extracellular oxidase released by the fungus under the conditions of slow growth

Yuxing Wong; Jian Yu

1999-01-01

294

DYES ADSORPTION ONTO ORGANOCLAY AND MCM-41  

Microsoft Academic Search

The adsorption of acid dye (Amido Naphthol Red G, AR1) onto hexadecyltrimethylammonium (HDTMA) chloride modified montmorillonite and basic dye (Basic Violet 10, BV10) onto MCM-41 was studied to examine the potential of organoclay and MCM-41 for the removal of acid and basic dye from wastewater. The revolutions of surface and pore structure of montmorillonite induced by surfactant modified process were

Lain-Chuen Juang; Cheng-Cai Wang; Chung-Kung Lee; Ting-Chu Hsu

295

Micelle dyeing with low liquor ratio for reactive dyes using dialkyl maleic acid ester surfactants  

Microsoft Academic Search

Micelle dyeing with low liquor ratio is novel fabric dyeing method for cleaner production. Preparation and interaction of dye-surfactant micelles using dibutyl maleic acid ester sodium sulfate surfactant were investigated by UV–Vis spectra. Dyeing properties of cellulose fabrics using micelle dyeing with low liquor ratio were discussed by color yields (K\\/S), color differences (?E), exhaustion (E), fixation (F) and reactivity

Kongliang Xie; Fangfang Cheng; Weiguo Zhao; Lei Xu

2011-01-01

296

Application of rare earth as mordant for the dyeing of ramie fabrics with natural dyes  

Microsoft Academic Search

Selecting appropriate metallic compounds as mordants is essential for dyeing with natural dyes. This paper presents the application\\u000a of rare earth compounds as mordant for the dyeing of ramie fabrics with four kinds of natural dyes. The influences of pre-mordanting,\\u000a simultaneous mordanting, and post-mordanting on the dyeing effect were explored. The post-mordanting was proved to give rise\\u000a to the highest

Guang Hong Zheng; Hong Bin Fu; Guang Ping Liu

297

Dyeing properties and colour fastness of wool dyed with indicaxanthin natural dye  

Microsoft Academic Search

This research work involves the dyeing of wool with indicaxanthin, a natural dye extracted from fruits of Opuntia ficus-indica. The optimal conditions for dye extraction were to mix 50g of Juice from cactus pears with 100mL of 80% aqueous ethanol as solvent for dye extraction. Liquid chromatography was applied for the separation. Two main dyes were obtained, which were identified

A. Guesmi; N. Ben Hamadi; N. Ladhari; F. Sakli

298

Determination of ranitidine hydrochloride in pharmaceutical preparations by titrimetry and visible spectrophotometry using bromate and acid dyes.  

PubMed

Four new methods using titrimetry and spectrophotometry are described for the determination of ranitidine hydrochloride (RNH) with potassium bromate as the oxidimetric reagent and acid dyes, methyl orange, indigo carmine and metanil yellow. In direct titrimetry (method A), the drug is titrated directly with bromate in acid medium and in the presence of excess of bromide using methyl orange indicator. In back titrimetry (method B), the drug is treated with a measured excess of bromate in the presence of bromide and acid, and the unreacted bromine is determined iodometrically. Both spectrophotometric methods are based on the oxidation of RNH by a known excess of bromate in acid medium and in the presence of excess of bromide followed by estimation of surplus oxidant by reacting with either indigo carmine (method C) or metanil yellow (method D), and measuring the absorbance at 610 or 530 nm. In methods B, C and D, reacted oxidant corresponds to the drug content. The experimental conditions are optimized. Titrimetric procedures are applicable over the ranges 1-10 mg (A) and 1-17 mg (B), and the reaction stoichiometry is found to be 1:1 (BrO(-)(3): RNH). In spectrophotometric methods, the absorbance is found to increase linearly with increasing concentration of RNH, which is corroborated by the calculated correlation coefficient (r) of 0.9984 (C) and 0.9976 (D). The systems obey Beer's law for 2-12 and 1-7 microg ml(-1), for methods C and D, respectively. Method D with a molar absorptivity of 9.82 x 10(4) l mol(-l) cm(-1) is found to be more sensitive than method C ( epsilon = 2.06 x l0(4) l mol(-1) cm(-1)). The limits of detection and quantification are reported for both the spectrophotometric methods. The proposed methods were applied successfully to the determination of RNH in tablets and injections. The reliability of the assay was established by parallel determination by the official method and by recovery studies. PMID:14871507

Basavaiah, K; Nagegowda, P

2004-02-01

299

Optofluidic Ring Resonator Dye Microlasers  

NASA Astrophysics Data System (ADS)

We discuss versatile, miniaturized optofluidic ring resonator (OFRR) dye lasers that can be operated regardless of the refractive index of the liquid. The OFRR is a piece of a thin-walled fused silica capillary that integrates the photonic ring resonator with microfluidics. In an OFRR dye laser, the active lasing materials (such as dyes) are passed through the capillary whereas the circular cross section forms a ring resonator and supports whispering gallery modes that provide optical feedback for lasing. Because of the high Q-factors extremely low lasing threshold is achieved (25 nJ/mm2). The operation wavelength can conveniently be changed by using different dyes and fine-tuned with solvent. The OFRR laser is excited through direct excitation or through efficient energy transfer. The laser can be efficiently out-coupled through a fiber taper in contact with the capillary, thus providing easy guiding for the laser emission. Theoretical analysis and experimental results for OFRR lasers are presented.

Shopova, Siyka I.; Lacey, Scott; White, Ian M.; Suter, Jonathan D.; Sun, Yuze; Fan, Xudong

300

Optofluidic ring resonator dye microlasers  

NASA Astrophysics Data System (ADS)

We report on the development of versatile, miniaturized optofluidic ring resonator (OFRR) dye lasers that can be operated regardless of the refractive index (RI) of the liquid. The OFRR is a piece of a thin-walled fused silica capillary that integrates the photonic ring resonator with microfluidics. In an OFRR dye laser, the active lasing materials (such as dye) are passed through the capillary whereas the circular cross section forms a ring resonator and supports whispering gallery modes (WGMs) that provide optical feedback for lasing. Due to the high Q-factors (> 10 9), extremely low lasing threshold can be achieved. The operation wavelength can conveniently be changed by using different dye and fine-tuned with solvent. The laser can be out-coupled through a fiber taper in touch with the capillary, thus providing an easy guiding for the laser emission. Our experiments demonstrate lasing through direct excitation and through efficient energy transfer (ET). Theoretical analysis and experimental results for OFRR lasers are presented.

Shopova, Siyka I.; Lacey, Scott; White, Ian M.; Sun, Yuze; Zhu, Hongying; Zhang, Po; Fan, Xudong

2008-02-01

301

Hair Dyes and Cancer Risk  

MedlinePLUS

... who had used permanent dyes for longer durations (15 or more years). However, a case-control study in Italy found no association between ... associated with bladder cancer risk: evidence from a case-control study. Cancer Epidemiology Biomarkers and Prevention 2006; 15(9):1746–1749. [PubMed Abstract

302

Organic Chemicals: Angels or Goblins?  

ERIC Educational Resources Information Center

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)

Ferguson, Lloyd N.

1978-01-01

303

Advanced oxidation processes in azo dye wastewater treatment.  

PubMed

The chemical degradation of synthetic azo dyes color index (C.I.) Acid Orange 7, C.I. Direct Orange 39, and C.I. Mordant Yellow 10 has been studied by the following advanced oxidation processes: Fenton, Fenton-like, ozonation, peroxone without or with addition of solid particles, zeolites HY, and NH4ZSM5. Spectrophotometric (UV/visible light spectrum) and total organic carbon measurements were used for determination of process efficiency and reaction kinetics. The degradation rates are evaluated by determining their rate constants. The different hydroxyl radical generation processes were comparatively studied, and the most efficient experimental conditions for the degradation of organic azo dyes solutions were determined. PMID:16894983

Papi?, Sanja; Koprivanac, Natalija; Bozi?, Ana Loncari?; Vujevi?, Dinko; Dragicevi?, Savka Kusar; Kusi?, Hrvoje; Peternel, Igor

2006-06-01

304

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

NASA Astrophysics Data System (ADS)

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.

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

2012-08-01

305

Characteristics of a Broadband Dye Laser Using Pyrromethene and Rhodamine Dyes  

NASA Technical Reports Server (NTRS)

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.

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

2011-01-01

306

Starburst triarylamine based dyes bearing a 3,4-ethylenedioxythiophene linker for efficient dye-sensitized solar cells.  

PubMed

Starburst triarylamine-based organic dyes (D1, D2, and D3) have been synthesized. For the three designed dyes, the starburst triarylamine group, thiophene (or 3,4-ethylenedioxythiophene), and cyanoacetic acid take the role of electron donor, ?-conjugation bridge, and electron acceptor, respectively. These compounds are characterized by photophysical, electrochemical, and theoretical computational methods. Nanocrystalline TiO2-based dye-sensitized solar cells were fabricated using these molecules as light-harvesting sensitizers. The overall efficiencies of the sensitized cells range from 5.48 to 6.15%. It was found that the introduction of the EDOT group in D3 bathochromically extended the absorption spectra, resulting in a leap in the photovoltaic performance in comparison to D2. Incorporation of a hydrophobic carbazole-containing segment at D2 relative with D1 retarded the electron transfer from TiO2 to the oxidized dye or electrolyte, leading to an increase of electron lifetime. PMID:23764958

Tan, Li-Lin; Chen, Hong-Yan; Hao, Li-Feng; Shen, Yong; Xiao, Li-Min; Liu, Jun-Min; Kuang, Dai-Bin; Su, Cheng-Yong

2013-07-28

307

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

PubMed

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

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

2011-08-30

308

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

ERIC Educational Resources Information Center

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…

Seng, Set; Kita, Masakazu; Sugihara, Reiko

2007-01-01

309

BODIPY Dyes In Photodynamic Therapy  

PubMed Central

BODIPY dyes tends to be highly fluorescent, but their emissions can be attenuated by adding substituents with appropriate oxidation potentials. Substituents like these have electrons to feed into photoexcited BODIPYs, quenching their fluorescence, thereby generating relatively long-lived triplet states. Singlet oxygen is formed when these triplet states interact with 3O2. In tissues, this causes cell damage in regions that are illuminated, and this is the basis of photodynamic therapy (PDT). The PDT agents that are currently approved for clinical use do not feature BODIPYs, but there are many reasons to believe that this situation will change. This review summarizes the attributes of BODIPY dyes for PDT, and in some related areas. PMID:23014776

Kamkaew, Anyanee; Lim, Siang Hui; Lee, Hong Boon; Kiew, Lik Voon; Chung, Lip Yong

2012-01-01

310

Methods of dyeing ceramic brick  

Microsoft Academic Search

The results of a study of the possibility of bulk dyeing of ceramic brick by incorporating manganese and iron ore and metallic\\u000a slags and sludges from electroplating plants in the pastes are reported. It was found that low-melting clays should first\\u000a be bleached with chalk or fireclay or kaolin impregnated with solutions of transition metal salts in order to attain

I. V. Pishch; G. N. Maslennikova; N. A. Gvozdeva; Yu. A. Klimosh; E. I. Baranovskaya

2007-01-01

311

Discharge excitation of dye vapors  

NASA Astrophysics Data System (ADS)

Experiments have been conducted to assess the feasibility of obtaining a discharge-pumped dye vapor laser. A 15 (or 50) cm active length, UV-preionized device has been developed which exhibits a specific power loading of the medium of approx. 5 MW/cu cm and will operate continuously at temperatures exceeding 400 C. Recently, hydrogen thyratron switching of the device and corona preionization have been installed to minimize jitter and dye fragmentation. Optimization of the rare gas/N2 diluent mixture has been completed and fragmentation studies for several dye molecules have been conducted. POPOP and alpha-NPO are excellent in the latter regard but Coumarin 6 rapidly decomposes in the discharge environment. The fluorescence efficiency of alpha-NPO is only 40 percent of that for POPOP under comparable conditions. BBO and PBBO are similar in structure and molecular weight to POPOP and appear to be excellent candidates for discharge excitation. Fluorescence and small signal gain measurements are in progress.

Eden, J. G.

1987-09-01

312

Dye laser traveling wave amplifier  

NASA Technical Reports Server (NTRS)

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.

Davidson, F.; Hohman, J.

1985-01-01

313

Evaluation of Polymethine Dyes as Potential Probes for Near Infrared Fluorescence Imaging of Tumors: Part - 1  

PubMed Central

Near-infrared (NIR) organic dyes have become important for many biomedical applications, including in vivo optical imaging. Conjugation of NIR fluorescent dyes to photosensitizing molecules (photosensitizers) holds strong potential for NIR fluorescence image guided photodynamic therapy (PDT) of cancer. Therefore, we were interested in investigating the photophysical properties, in vivo tumor-affinity and fluorescence imaging potential of a series of heterocyclic polymethine dyes, which could then be conjugated to certain PDT agents. For our present study, we selected a series of symmetrical polymethine dyes containing a variety of bis-N-substituted indole or benzindole moieties linked by linear conjugation with and without a fused substituted cyclohexene ring. The N-alkyl side chain at the C-terminal position was functionalized with sulfonic, carboxylic acid, methyl ester or hydroxyl groups. Although, among the parent cyanine dyes investigated, the commercially available, cyanine dye IR783 (3) (bis-indole-N-butylsulfonate)-polymethine dye with a cyclic chloro-cyclohexene moiety showed best fluorescence-imaging ability, based on its spectral properties (?Abs=782 nm, ?Fl=810 nm, ? = 261,000 M-1cm-1, ?Fl?0.08) and tumor affinity. In addition to 3, parent dyes IR820 and Cypate (6) were also selected and subjected to further modifications by introducing desired functional groups, which could enable further conjugation of the cyanine dyes to an effective photosensitizer HPPH developed in our laboratory. The synthesis and biological studies (tumor-imaging and PDT) of the resulting bifunctional conjugates are discussed in succeeding paper (Part-2 of this study). PMID:24019854

James, Nadine S.; Chen, Yihui; Joshi, Penny; Ohulchanskyy, Tymish Y.; Ethirajan, Manivannan; Henary, Maged; Strekowsk, Lucjan; Pandey, Ravindra K

2013-01-01

314

Optical enhancement of dye-doped PDLC by additional dye-LC layer coating  

NASA Astrophysics Data System (ADS)

Dye-doped PDLC has a high probability to be used as reflective optical shutter due to its good reflectance compared to normal PDLC or LC shutter structures. The black state can be significantly enhanced by the minimized surface scattering between polymer and LC surface, which makes a harmful result to the contrast ratio, one of most important factors for optical shutter. To remove this scattering effect, we have developed new combinational structure, consisted of guest dye-doped LC (DLC) and dye-doped PDLC (DPDLC). In the newly fabricated dye-doped PDLC structure, the front location of dye-doped LC layer can remove the light scattering effect of the surface of single dye PDLC structure. The proposed process can also remove the randomly distributed dyes in polymer area of dye PDLC. This technique enhances the reflectance as well as the contrast ratio.

Jung, Jae Eun; Lee, Gae Hwang; Jang, Jae Eun; Hwang, Kyu Young; Ahmad, Farzana; Muhammad, Jamil; Woo Lee, Jin; Jeon, Young Jae

2011-11-01

315

Dye Photodestruction in a Solid-State Dye Laser with a Polymeric Gain Medium  

NASA Astrophysics Data System (ADS)

The process of dye photodestruction in a solid-state dye laser is studied, and implemented is a polymeric gain medium doped with a strongly concentrated dye. The behavior of the conversion efficiency in the polymeric gain medium pumped with different laser-pulse repetition rates and the process of dye photobleaching are analyzed. The contribution of the heating of the host material into the dye molecules deactivation is discussed. The negative effect of high dye concentration on the dye stability under a high pump repetition rate is reported and analyzed for the first time to my knowledge. A comparison of the present results with recently published data demonstrates the major role of photodestruction, rather than direct thermodestruction, in the dye stability of the solid-state gain medium. The role of additives with low molecular weights in the polymeric matrix, for increasing the stability of the gain material, is discussed.

Popov, Sergei

1998-09-01

316

Laccase-assisted dyeing of cotton.  

PubMed

Cotton cellulose was dyed "in situ" with a polymeric dye generated by oxidative coupling of colourless 2,5-diaminobenzenesulfonic acid and 1-hydroxyphenol (catechol) with laccase. Up to 70% dye fixation was obtained increasing the concentration of catechol less soluble upon oxidation from 1 to 10 mmol, while 1 mmol of diamine was used. Dye fixation was not achieved using equal molar concentrations of the reagents. PMID:16791731

Hadzhiyska, Hristina; Calafell, Margarita; Gibert, Josep M; Dagà, Josep M; Tzanov, Tzanko

2006-05-01

317

Application of Chitosan in Remediation of Dyes  

Microsoft Academic Search

\\u000a Chitosan is derived from Chitin, which is the exoskeleton of a crab or shrimp shell and some other crustaceans. This project\\u000a explores this characteristic behavior of chitosan in the removal of dye from solution as a model for the potential application\\u000a in textile industry wastewater treatment. Azure dye was used as the model dye used in the textile industry wastewater

Gbekeloluwa B. Oguntimein; Olatunde Animashaun; Ivie Okpere

318

Residual contaminants in dye-penetrant testing  

SciTech Connect

Components of the dye-penetrant-testing process were characterized by microanalytical methods. Particulate material of a size range, which was small enough to plug the small leaks in thin-walled cans, was found. Testing of simulated leaks before and after dye-penetrant examination showed that the dye-penetrant testing had a high probability of plugging leaks < 1 x 10/sup -4/ atm-cm/sup 3//s of helium in size.

McLaughlin, J.F.; Schneider, P.G.; Eager, M.H.

1981-04-13

319

Ultrasonic dyeing of cationized cotton fabric with natural dye. Part 2: Cationization of cotton using Quat 188  

Microsoft Academic Search

The dyeing of cationized cotton fabric with 3-chloro-2-hydroxypropyltrimethyl ammonium chloride 69% (Quat 188) using Cochineal dye was studied using both conventional and ultrasonic techniques. Factors affecting dye extraction and dye bath exhaustion were investigated. The results indicated that the dye extraction by ultrasound at 300W was more effective at lower temperatures and times than conventional extraction. Also, the colour strength

M. M. Kamel; M. M. El Zawahry; N. S. E. Ahmed; F. Abdelghaffar

2011-01-01

320

Dyeing of modified acrylic fibers with curcumin and madder natural dyes  

Microsoft Academic Search

Hydrophobic fibers are highly crysta lline and non-polar polymers hence pose a big problem for dyers. Modified acrylic fiber\\u000a containing different amounts of amidoxime groups as a function of the nitrogen content was obtained and dyed with curcumin\\u000a and madder natural dyes. The dyeing parameters, such as dye concentration, dye bath pH, salt concentration, temperature, and\\u000a time and the effect

Reda M. El-Shishtawy; G. M. Shokry; Nahed S. E. Ahmed; M. M. Kamel

2009-01-01

321

Concrete Embedded Dye-Synthesized Photovoltaic Solar Cell  

PubMed Central

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

Hosseini, T.; Flores-Vivian, I.; Sobolev, K.; Kouklin, N.

2013-01-01

322

A bifunctionalized dye-sensitized TiO(2) film for efficient degradation of methyl orange under visible light irradiation.  

PubMed

A new bifunctionalized TiO(2) film containing a dye-sensitized region and a degradation region was described. A similar structure of dye-sensitized solar cell (DSSC) was fabricated in the dye-sensitized region to accomplish separation of electrons from positive charges, and separation of dye from pollutants to avoid dye decomposition. The bifunctionalized TiO(2) film electrode and anode electrode can degrade methyl orange (MO) in reactors A and B, respectively. The degradation efficiency was enhanced remarkably by an external electrical potential. The decolorization of MO reaches as high as 95% after 2 h visible light irradiation at an external potential of 0.5 V along with a loss of 41% total organic carbon (TOC). The possible reason for the improvement of degradation by external DC potential was discussed. Effects of pH and inorganic salts on the decolorization are present. PMID:22766876

Wu, Quanping; Zhao, Jun; Qin, Guohui; Wang, Xuezheng; Tong, Xinli; Xue, Song

2012-01-01

323

Evaluation of the performance of calix[8]arene derivatives as liquid phase extraction material for the removal of azo dyes.  

PubMed

This paper presents a study on the removal of azo dyes (Reactive Black 5, Trapaeolin 000, Methyl Orange and Direct Violet 51) with calix[n]arene derivatives from aqueous solution into the organic phase in order to explore the potential use of calixarenes as low-cost efficient extractants for wastewater dye removal. The carboxylic acid derivative of calix[8]arene shows highest affinity towards the azo dyes. The influence of NaCl (present in the solution) on extraction process was also studied. The extent of the dye removal increased with the addition of NaCl. The proposed extraction mechanism involves several kinds of interactions: electrostatic repulsion between carboxylic acid groups of calix[8]arenes and sulfonate groups of azo dyes, hydrogen bonding and formation of an inclusion complex due to three dimensional cavity type calix[n]arene molecules through host-guest interactions. PMID:18321641

Gungor, Omer; Yilmaz, Aydan; Memon, Shahabuddin; Yilmaz, Mustafa

2008-10-01

324

Retail Demand for Natural Dye Plants and Dye Plant Products: A Conjoint Analysis  

Microsoft Academic Search

Herbalists, fiber artists, and herb growers are increasingly interested in growing, marketing, and using local plants as natural dyes. As the market in the United States and Canada develops, fiber art and quilting stores are the primary retail market outlets for natural dye plants and dye plant products. Conjoint analysis was used to evaluate U.S. and Canadian retailer interest in

Yuhui Zhou; Constance L. Falk; Dawn M. Vanleeuwen

2012-01-01

325

DOI: 10.1002/cphc.201000854 Incorporating Multiple Energy Relay Dyes in Liquid Dye-  

E-print Network

DOI: 10.1002/cphc.201000854 Incorporating Multiple Energy Relay Dyes in Liquid Dye- Sensitized*[a] 1. Introduction The dye-sensitized mesoscopic solar cell (DSC) has been inten- sively investigated as a promising photovoltaic cell. Its ecologi- cal and economical fabrication processes make it an attractive

McGehee, Michael

326

Template-free synthesis of nanostructured Cd(x)Zn(1-x)S with tunable band structure for H2 production and organic dye degradation using solar light.  

PubMed

We have demonstrated a template-free large-scale synthesis of nanostructured Cd(x)Zn(1-x)S by a simple and a low-temperature solid-state method. Cadmium oxide, zinc oxide, and thiourea in various concentration ratios are homogenized at moderate temperature to obtain nanostructured Cd(x)Zn(1-x)S. We have also demonstrated that phase purity of the sample can be controlled with a simple adjustment of the amount of Zn content and nanocrystalline Cd(x)Zn(1-x)S(x = 0.5 and 0.9) of the hexagonal phase with 6-8 nm sized and 4-5 nm sized Cd(0.1)Zn(0.9)S of cubic phase can be easily obtained using this simple approach. UV-vis and PL spectrum indicate that the optical properties of as synthesized nanostructures can also be modulated by tuning their compositions. Considering the band gap of the nanostructured Cd(x)Zn(1-x)S well within the visible region, the photocatalytic activity for H2 generation using H2S and methylene blue dye degradation is performed under visible-light irradiation. The maximum H2 evolution of 8320 ?mol h(-1)g(-1) is obtained using nanostructured Cd(0.1)Zn(0.9)S, which is four times higher than that of bulk CdS (2020 ?mol h(-1) g(-1)) and the reported nanostructured CdS (5890 ?mol h(-1)g(-1)). As synthesized Cd(0.9)Zn(0.1)S shows 2-fold enhancement in degradation of methylene blue as compared to the bulk CdS. It is noteworthy that the synthesis method adapted provides an easy, inexpensive, and pollution-free way to synthesize very tiny nanoparticles of Cd(x)Zn(1-x)S with a tunnable band structure on a large scale, which is quite difficult to obtain by other methods. More significantly, environmental benign enhanced H2 production from hazardous H2S using Cd(x)Zn(1-x)S is demonstrated for the first time. PMID:23672184

Garaje, Sunil N; Apte, Sanjay K; Naik, Sonali D; Ambekar, Jalindar D; Sonawane, Ravindra S; Kulkarni, Milind V; Vinu, Ajayan; Kale, Bharat B

2013-06-18

327

The effect of dye coverage on the performance of dye-sensitized solar cells with a cobalt-based electrolyte.  

PubMed

The effect of dye coverage of the mesoporous TiO2 electrode on the performance of dye-sensitized solar cells based on the cobalt tris(bipyridine) electrolyte and the D35 dye was studied in detail. The dye coverage was controlled by using a dye bath with different dye concentrations and containing an inert salt, LiClO4, which was found to promote equilibrium conditions in the dye adsorption process. The amount of adsorbed D35 dye on mesoporous TiO2 was reasonably fit using the Langmuir adsorption isotherm, with a binding constant of 55?000 M(-1). Upon increasing the dye coverage on the TiO2 electrode, the electron lifetime in the dye-sensitized solar cell increased remarkably, demonstrating the blocking behavior of the D35 dye at the TiO2-electrolyte interface. Consequently, the solar cell efficiency increased dramatically with the D35 dye coverage. PMID:24668285

Pazoki, Meysam; Lohse, Peter William; Taghavinia, Nima; Hagfeldt, Anders; Boschloo, Gerrit

2014-05-14

328

Color Tuning of an Acidic Blue Dye by Intercalation into the Basic Interlayer Galleries of a Poly(allylamine)/Synthetic Fluoromica  

E-print Network

Color Tuning of an Acidic Blue Dye by Intercalation into the Basic Interlayer Galleries of a Poly conjugated system and a free sulfonate group. Introduction Many organic dyes are used in the food, cosmetics traditional inorganic pigments such as iron oxides, iron blue, ultramarine blue, and trivalent chromium oxide

329

Solvent-enhanced Dye Diffusion in Polymer This-Films for OLED Application F. Pschenitzka, K. Long, and J. C. Sturm  

E-print Network

Solvent-enhanced Dye Diffusion in Polymer This-Films for OLED Application F. Pschenitzka, K. Long in polymer films for organic light-emitting diode (OLED) application is introduced. After an initial dye by 150 °C. OLEDs with 0.4% external quantum efficiency were demonstrated. The materials used

330

Dye laser tuning with pellicles.  

NASA Technical Reports Server (NTRS)

Thin nitrocellulose membranes (pellicles) are shown to exhibit properties which make them suitable for intracavity tuning elements in high-energy pulsed dye lasers. Uncoated pellicles of 2-micron and 8-micron thickness with surface figures of lambda/1 are shown to closely approximate the properties of low-finesse etalons with wide free spectral ranges. Pellicles of 8-micron thickness, coated on both surfaces with 50% reflectivity multilayer dielectrics, are shown to be effective as spectral narrowing elements with peak transmission greater than 80% and resultant laser linewidths of 0.57 nm full width at half-maximum.

Mumola, P. B.

1973-01-01

331

On the correlation between dye coverage and photoelectrochemical performance in dye-sensitized solar cells.  

PubMed

Concentration depth profiles of the ruthenium based dyes Z907 and N719 adsorbed onto titania are measured directly and used for determining the adsorption isotherm of the dyes. Dye layers formed by both grow in islands on the titania which do not cover the entire titania surface even at the maximum coverage. Impedance spectroscopy in conjunction with the adsorption isotherms shows that recombination losses mainly appear between the dye and the electrolyte solution. The short circuit current and the efficiency increase linearly with the dye coverage. The open circuit voltage slightly increases with increasing dye coverage which is interpreted as most likely to be a consequence of the higher charge in the particles upon higher dye loading on the TiO2 surface. PMID:24263223

Johansson, Viktor; Ellis-Gibbings, Lilian; Clarke, Trevor; Gorlov, Mikhail; Andersson, Gunther G; Kloo, Lars

2014-01-14

332

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

NASA Astrophysics Data System (ADS)

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.

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

2011-07-01

333

Liquid crystalline behaviour of some azobenzene dyes  

Microsoft Academic Search

A number of 4-aminoazobenzene dye units have been synthesised and subjected to thermal analysis by differential scanning calorimetry and hot stage optical microscopy. It is observed that liquid crystalline phase behaviour exists for those dyes having a nitro group in the 4-position on the terminal phenyl ring and with a short hydrocarbon ‘tail’ at the amino site with a terminal

D. Campbell; L. R. Dix; P. Rostron

1995-01-01

334

A micro-cavity fluidic dye laser  

Microsoft Academic Search

We have successfully fabricated and characterized a micro-cavity fluidic dye laser with metallic mirrors, which can be integrated with other microfluidic systems without adding further process steps. A laser dye solution is pumped through a microfluidic channel containing the laser cavity. The microfluidic channel structure, which is formed in SU-8 photoresist, is sandwiched between Pyrex glass wafers, bonded together at

Bjarne Helbo; Anders Kristensen; Aric Menon

2003-01-01

335

Fungal decolorization of dye wastewaters: a review  

Microsoft Academic Search

In recent years, there has been an intensive research on fungal decolorization of dye wastewater. It is becoming a promising alternative to replace or supplement present treatment processes. This paper examines various fungi, living or dead cells, which are capable of decolorizing dye wastewaters; discusses various mechanisms involved; reports some elution and regeneration methods for fungal biomass; summarizes the present

Yuzhu Fu; T Viraraghavan

2001-01-01

336

Fate of commercial disperse dyes in sediments  

SciTech Connect

Kinetics of disappearance of seven different disperse dyes were determined in compacted sediments at room temperature. The commercial dyes (in dispersed solid form) were representative of nitroazo, anthraquinone, and quinoline structures that are widely used. Reaction rates were found to be first order over at least two half-lives and were different for the three groups of dyes. Half-lives were on the order of hours, days and months for the nitroazobenzene, aminoanthraquinone, and quinoline dyes, respectively. Stability of the latter is consistent with detection of a quinoline dye in treatment plant sludge and in sediment from a water body receiving treated effluent. The azobenzene dyes are degraded by cleavage of the azo group to give anilines and ring-substituted phenylenediamines from the diazo component of the molecule. Products from the other portion (coupling component) of the molecule are unidentified, as yet, but are expected to be N,N-disubstituted phenylenediamines. Products of the anthraquinone dyes were unidentified, except for the case of a nitrated dye on which the nitro group was reduced.

Yen, C.P.C.; Perenich, T.A.; Baughman, G.L.

1991-01-01

337

Using dye markers to reduce pesticide use  

E-print Network

of the food dye Acid Blue 9 to the spray mix (e.g. through the use of 4 l ha-1 Dysol Turquoise; 40% Acid Blue of trees to protect against Hylobius abietis, a 0.8% dilution of the active ingredient Acid Blue 9 good, economic results when relatively high concentrations of dye are used on small areas, for example

338

Dyeing with polyaniline synthesis in fibers  

Microsoft Academic Search

Physicochemical aspects of dyeing with polyaniline are considered. It is shown to be possible to attain the first percolation\\u000a threshold for electrically conducting polyamide fabric. An equation has been obtained for estimating the thermodynamic affinity\\u000a of the dye for the fiber.

O. V. Romankevich; Ya. V. Red’ko; Ya. O. Romankevich

2008-01-01

339

Use of slag for dye removal  

SciTech Connect

Adsorption techniques employing activated carbon have been found to be reasonably effective in the removal of some of the ionic impurities in water. However, economic considerations may require the use of inexpensive sorbents which are either naturally available or available as waste products from manufacturing processes. Slag is one such waste product obtained during the manufacture of steel, and the present study investigates dye removal characteristics of slag from colored waters. Aqueous solutions prepared from commercial grade acid, basic, and disperse dyes were used in this study, and batch pH, kinetic, and isotherm studies were undertaken on a laboratory scale. The data were evaluated for applicability to the Langmuir, Freundlich, and BET isotherm models, and the removal capacity of slag was compared with that of granular activated carbon. Results indicated approximately 94% removal of the disperse dye by slag, compared with a removal of approximately 49% achieved by activated carbon. Removal of acid dyes (dyes containing anionic groups) was reasonably good (approximately 47 and 74%), though not as good as obtained using activated carbon (approximately 100%). Column studies were conducted with a disperse dye (nonionic, slightly soluble in water), and analysis of data showed a sorption capacity of 1.3 mg of disperse dye per gram of slag. However, effluent dye concentrations were found to be higher than the permissible levels for discharge to receiving waters.

Ramakrishna, K.R.; Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

1998-09-01

340

Basic dye adsorption on activated carbon  

Microsoft Academic Search

The adsorption of Victoria Blue dye (Basic Blue 26) on carbon has been investigated. Equilibrium data have been found to obey the Langmuir isotherm. The effects of contact time, agitation, initial dye concentration and carbon particle size range were also studied.

Gordon McKay

1979-01-01

341

Ternary bulk heterojunction solar cells: addition of soluble NIR dyes for photocurrent generation beyond 800 nm.  

PubMed

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

Lim, Bogyu; Bloking, Jason T; Ponec, Andrew; McGehee, Michael D; Sellinger, Alan

2014-05-14

342

Decolourisation of dyes under electro-Fenton process using Fe alginate gel beads.  

PubMed

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

Rosales, E; Iglesias, O; Pazos, M; Sanromán, M A

2012-04-30

343

Three-dimensional graphene oxide nanostructure for fast and efficient water-soluble dye removal.  

PubMed

In this study, we demonstrated the potential of graphene nanomaterials as environmental pollutant adsorbents by utilizing the characteristics of ultralarge surface area and strong ?-? interaction on the surface. We generated a three-dimensional (3D) graphene oxide sponge (GO sponge) from a GO suspension through a simple centrifugal vacuum evaporation method, and used them to remove both the methylene blue (MB) and methyl violet (MV) dyes which are main contaminants from the dye manufacturing and textile finishing. The efficiency and speed of dye adsorption on a GO sponge was investigated under various parameters such as contact time, stirring speed, temperature, and pH. The adsorption process shows that 99.1% of MB and 98.8% of MV have been removed and the equilibrium status has been reached in 2 min. The 3D GO sponge displays adsorption capacity as high as 397 and 467 mg g(-1) for MB and MV dye, respectively, and the kinetic data reveal that the adsorption process of MB and MV dyes is well-matched with the pseudo second-order model. The MB and MV adsorption on the 3D GO sponge involved in endothermic chemical adsorption through the strong ?-? stacking and anion-cation interaction with the activation energy of 50.3 and 70.9 kJ mol(-1), respectively. The 3D GO sponge has demonstrated its high capability as an organic dye scavenger with high speed and efficiency. PMID:22206476

Liu, Fei; Chung, Soyi; Oh, Gahee; Seo, Tae Seok

2012-02-01

344

Dye removal by surfactant encapsulated polyoxometalates.  

PubMed

A novel surfactant encapsulated polyoxometalate (SEP) has been synthesized by using a simple ion-exchange reaction. The prepared SEP complex was found to self-assemble into nanospherical particles whose morphology and component were characterized by TEM and XPS. The SEP was further incorporated into polyvinylidene fluoride (PVDF) to fabricate SEP incorporated composite membrane (SEP-M). Both the SEP and SEP-M exhibited excellent dye removal activities, which is for the first time reported as an intriguing property of the SEP. A regeneration scheme for SEP-M was successfully proposed without any loss of dye removal efficiency. Detailed mechanism studies were carried out to elucidate the nature of dye decolorization. Ion exchange was revealed to play a dominant role in the dye removal process. The current research not only renders a new example for the simple and direct synthesis of SEP but more importantly provides an efficient dye removal methodology. PMID:25194560

Yao, Lei; Lua, Shun Kuang; Zhang, Lizhi; Wang, Rong; Dong, ZhiLi

2014-09-15

345

Effectiveness of photosensitive dye during uptake and redistribution  

NASA Astrophysics Data System (ADS)

The location of photosensitive dye within a cell will affect the efficacy of photodynamic therapy (PDT). This report demonstrates that during the first 3 hours of dye (Photofrin porfimer) uptake from a liquid medium, the dye is diffusely distributed within the cell. After 24 hours of dye uptake, the dye is localized in specific sites within the cell. Fluorescence spectroscopy demonstrated that the 3-hour dye's emission peak near 635 nm was slightly blue shifted for the localized 24-hour dye. This paper demonstrates that the diffuse dye (at 3 hours) is more effective for PDT than the localized dye (at 24 hours). The amount of diffuse dye within the cell that is required to achieve an LD50 (50% lethal dose) is 1.5-fold to 4.5- fold less than the amount of localized dye required, using the same light exposure. The range of 1.5 - 4.5-fold refers to the results for four cell lines.

He, Xiao-Yan; Jacques, Steven L.; Gofstein, Gary

1992-06-01

346

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

PubMed

A series of simple phenothiazine-based dyes, namely, TP, EP, TTP, ETP, and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye-sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (Jsc = 15.2?mA?cm(-2), Voc =0.783?V, fill factor (FF) = 0.679) and 7.87?% (Jsc = 16.1?mA?cm(-2), Voc = 0.717?V, FF = 0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I(-)/I3(-) redox couple. By replacing the T group with the E unit, EP-based DSSCs had a slightly lower PCE of 7.98?% with a higher short-circuit photocurrent (Jsc) of 16.7?mA?cm(-2). The dye ETP, with a mixture of E and T, had an even lower PCE of 5.62?%. Specifically, the cell based on the dye EEP, with a dimer of E, had inferior Jsc and Voc values and corresponded to the lowest PCE of 2.24?%. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies. PMID:24715494

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

2014-05-19

347

Diffusion and birefringence of bioactive dyes in a supramolecular guanosine hydrogel.  

PubMed

Transparent self-standing supramolecular hydrogels were readily prepared by the potassium-ion-mediated self-organization of guanosine and 8-bromoguanosine whilst the individual components precipitated within a few hours. VT-NMR spectroscopy showed that bromoguanosine was a superior gelator compared to guanosine. XRD analysis showed that gel formation was caused by stacked G-quartets. AFM analysis revealed dendritic architectures of the nanofibers in the two-component hydrogel network. DSC profiles showed that the hybrid hydrogels underwent sol-gel transition at lower temperature than the pure guanosine and bromoguanosine hydrogels. Interestingly, bioactive dyes, such as rose bengal, rhodamine-6-G, and fluorescein, could be diffused and released in a controlled manner. UV/Vis absorption and fluorescence spectroscopy and CLSM were used to investigate the diffusion behavior of dyes in the hydrogel network. These dyes exhibited strong birefringence in the gel network (0.07-0.1) as a result of the anisotropic organization. PMID:22461410

Das, Rabindra Nath; Kumar, Y Pavan; Pagoti, Sreenivasarao; Patil, Avinash J; Dash, Jyotirmayee

2012-05-01

348

Near field enhanced photocurrent generation in p-type dye-sensitized solar cells.  

PubMed

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

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

349

Near Field Enhanced Photocurrent Generation in P-type Dye-Sensitized Solar Cells  

NASA Astrophysics Data System (ADS)

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.

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

2014-02-01

350

Optical properties of thin merocyanine dye layers for photovoltaic applications  

NASA Astrophysics Data System (ADS)

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.

Dikova, J.; Kitova, S.; Stoyanova, D.; Vasilev, A.; Deligeorgiev, T.; Angelova, S.

2014-05-01

351

Calibration of Far West Technology (FWT-60) radiachromic dye dosemeters  

SciTech Connect

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.

Mincher, B.J.; Zaidi, M.K.

1992-01-01

352

Calibration of Far West Technology (FWT-60) radiachromic dye dosemeters  

SciTech Connect

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.

Mincher, B.J.; Zaidi, M.K.

1992-08-01

353

New cyanine dyes or not? Theoretical insights for model chains.  

PubMed

The quest of organic dyes presenting improved electronic features has been extremely active during the last decades, as new structures are necessary to build novel materials such as dye-sensitized solar cells, nonlinear optics commutators, or molecular photochromic switches. Cyanine derivatives occupy a key spot in that scene, as they present intense absorption bands and tunable colors, even when a relatively short ?-conjugated path is used. This behavior has often been interpreted as a consequence of a negligible bond length alternation. Recently, Thorley et al. have designed and characterized new cationic compounds that possess the cyanine electronic features, though presenting sizable bond length alternation (Angew. Chem. Int. Ed.2008, 47, 7095-7098). In this contribution, I investigate, with quantum mechanical tools, the size dependence of these properties in model symmetric dyes displaying Thorley's patterns. Extended chains are simulated in order to obtain insights into the chain length convergence, and the results are compared to those obtained at the same level of theory for classical cyanine architectures. This theoretical work is a step toward the rational development of more efficient ?-conjugated compounds. PMID:21361307

Jacquemin, Denis

2011-03-24

354

Azo Dye Biodecolorization Enhanced by Echinodontium taxodii Cultured with Lignin  

PubMed Central

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

Meng, Jing; Yu, Hongbo; Zhang, Xiaoyu

2014-01-01

355

KOH catalysed preparation of activated carbon aerogels for dye adsorption.  

PubMed

Organic carbon aerogels (CAs) were prepared by a sol-gel method from polymerisation of resorcinol, furfural, and hexamethylenetetramine catalysed by KOH at around pH 9 using ambient pressure drying. The effect of KOH in the sol-gel on CA synthesis was studied. It was found that addition of KOH prior to the sol-gel polymerisation process improved thermal stability of the gel, prevented the crystallinity of the gel to graphite, increased the microporosity of CA and promoted activation of CA. The CAs prepared using the KOH catalyst exhibited higher porosity than uncatalysed prepared samples. Activation in CO(2) at higher temperature also enhanced the porosity of CAs. Adsorption tests indicated that the CAs were effective for both basic and acid dye adsorption and the adsorption increased with increasing surface area and pore volume. The kinetic adsorption of dyes was diffusion control and could be described by the second-order kinetic model. The equilibrium adsorption of dyes was higher than activated carbon. PMID:21345448

Ling, Sie King; Tian, H Y; Wang, Shaobin; Rufford, Thomas; Zhu, Z H; Buckley, C E

2011-05-01

356

Solid-state dye-sensitized solar cells fabricated with nanoporous TiO 2 and TPD dyes: Analysis of penetration behavior and I-V characteristics  

NASA Astrophysics Data System (ADS)

We present the synthesis, electrochemical properties and device-based investigation of triphenylene diamine (TPD) sensitizer with an extended ? system consisting of donor, electron conducting and anchoring group for solid-state dye-sensitized solar cells. Solid-state dye-sensitized solar cells were fabricated using blocking TiO2 electrodes, nanoporous TiO2 electrodes and the organic hole-transporting medium, HTM (spiro-OMeTAD) in a fluorine doped tin oxide/blocking TiO2/nanoporous TiO2/TPDs/hole transport material/Au configuration. Solid state dye sensitized solar cell consisting of TPD_2 as sensitizer on mesoporous TiO2 shows the best results with a short-circuit current of 2.8 mA/cm2, an open circuit voltage of 835 mV and an overall conversion efficiency of 0.97%.

Erten-Ela, Sule; Brendel, Johannes; Thelakkat, Mukundan

2011-06-01

357

A comparative study of a polyene-diphenylaniline dye and Ru(dcbpy) 2(NCS) 2 in electrolyte-based and solid-state dye-sensitized solar cells  

Microsoft Academic Search

A small organic sensitizer, the polyene-diphenylaniline dye D5, was compared with the standard sensitizer N719 (Ru(dcbpy)2(NCS)2) in a dye-sensitized solar cell investigation. In solar cells with relatively thin layers of mesoporous TiO2 (<3 ?m) D5 outperformed N719 because of its high extinction coefficient. D5 showed also better performance than N719 in the case of sensitization of mesoporous ZnO. In solid-state solar

G. Boschloo; T. Marinado; K. Nonomura; T. Edvinsson; A. G. Agrios; D. P Hagberg; L. Sun; M. Quintana; C. S. Karthikeyan; M. Thelakkat; A. Hagfeldt

2008-01-01

358

DFT and TD-DFT study on geometries, electronic structures and electronic absorption of some metal free dye sensitizers for dye sensitized solar cells.  

PubMed

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

Mohr, T; Aroulmoji, V; Ravindran, R Samson; Müller, M; Ranjitha, S; Rajarajan, G; Anbarasan, P M

2015-01-25

359

Measured binding coefficients for iodine and ruthenium dyes; implications for recombination in dye sensitised solar cells.  

PubMed

We have measured the binding coefficients of iodine to three dyes used in Dye Sensitised Solar Cells (DSSCs). Binding coefficients are quantified via the effect of iodine binding on the UV-vis spectrum of the dye. From iodine titration curves of dye sensitised TiO(2) films we find that the binding coefficients of iodine to the dyes C101, N719 and AR24 (vide infra) are in the range of 2000-4000 M(-1). From FTIR results and molecular modelling we show the iodine binds to the thiocyanate group in all these dyes. For the AR24 dye we present evidence that iodine also binds to the amine moiety on this dye. With these binding coefficients we show that the dye-iodine complex will be present at much higher concentrations than free iodine in the pore structure of a DSSC. As we have recently shown that iodine (rather than tri-iodide) is the dominant acceptor in electron recombination, the concentration dye-iodine complexes could influence recombination rates and thus V(oc). By comparison of recombination data on full cells, we show that AR24 accelerates recombination by a factor of 7 over N719, presumably due to the iodine binding to the amine group. We leave open the question why iodine binding to the amine group seems to have a stronger effect on the recombination than does binding to the thiocyanate. PMID:23070136

Li, Xiaoe; Reynal, Anna; Barnes, Piers; Humphry-Baker, Robin; Zakeeruddin, Shaik Mohammed; De Angelis, Filippo; O'Regan, Brian C

2012-11-28

360

Application of Temperature-Dependent Fluorescent Dyes to the Measurement of Millimeter Wave Absorption in Water Applied to Biomedical Experiments  

PubMed Central

Temperature sensitivity of the fluorescence intensity of the organic dyes solutions was used for noncontact measurement of the electromagnetic millimeter wave absorption in water. By using two different dyes with opposite temperature effects, local temperature increase in the capillary that is placed inside a rectangular waveguide in which millimeter waves propagate was defined. The application of this noncontact temperature sensing is a simple and novel method to detect temperature change in small biological objects.

Popenko, Oleksandr

2014-01-01

361

A microporous glass-polymer composite as a new material for solid-state dye lasers: II. Lasing properties  

SciTech Connect

The conversion efficiency and service life of the laser elements based on a polymer-filled microporous glass (PFMPG) composite doped with organic dyes are studied. It is shown that both the conversion efficiency and the service life of the laser elements achieve the values obtained for the same dyes in bulk polymer elements. Good lasing characteristics of the elements studied are advantageously combined with the high mechanical strength and high laser damage resistance and excellent thermooptical properties of the PFMPG composite. (lasers)

Aldag, H R; Pacheco, D P [Physical Sciences Inc., 20 New England Business Center, Andover (United States); Dolotov, S M; Ponomarenko, E P; Reznichenko, A V ['Alfa-Akonis' Research and Devices Enterprise, Dolgoprudnyi, Moscow region (Russian Federation); Koldunov, M F ['Optronika' R and D Enterprise, Dolgoprudnyi, Moscow region (Russian Federation); Kravchenko, Ya V; Manenkov, Aleksandr A [A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Roskova, G P; Tsekhomskaya, T S [I.V. Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, St.Petersburg (Russian Federation)

2000-12-31

362

Effect of the interaction between dye and acetic acid on the decomposition of Basic Green 4 with additive by ozone.  

PubMed

This research investigated the ozonation of Basic Green 4 (BG4) under the presence of acetic acid (AA). This acid is used as a textile additive for many industrial dyes derived from triphenylmethane. Determining the effect of this additive on discoloration, degradation dynamics, and final by-product distribution is the main objective of this study. The reaction system was the ozonation of a dye solution in co-solvents. This solution (dye and AA) was considered a simplified version of real BG4 dyeing wastewaters supplied with additives. The dye concentration was set to 50, 150, and 250 mg/L without pH adjustment (pH = 3). This low value was forced by the AA. Ozonation reaction with dye was mainly done by a direct molecular mechanism. The discoloration dynamics of BG4 without and with the additive were determined by ultraviolet and visible wavelength spectroscopy. The dye decomposition and the intermediate and final product formation-decomposition dynamics were followed by high-performance liquid chromatography. The effects of AA in the ozonation results were significant in the following ways: 1) a possible complex, formed between AA and the dye, changed ozone consumption; 2) the presence of additive decelerated the dye discoloration and decomposition; and 3) the number of by-products was dissimilar in both systems, with and without the additive the ozonation. The accumulation of organic acids with low molecular weight was determined in both systems, with and without the additive. Only one by-product was obtained in ozonation when AA participated in the reactor. A possible reaction mechanism is proposed for the system dye-AA-ozone. PMID:24117080

Pérez, Arizbeth A; Poznyak, Tatiana I; Chairez, Jorge I

2014-01-01

363

Interfacial Properties of a Hydrophobic Dye in the Tetrachloroethylene-Water-Glass Systems  

SciTech Connect

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.

Tuck, D.M.

1999-02-23

364

Capillary driven tunable optofluidic DFB dye lasers  

NASA Astrophysics Data System (ADS)

We present the design and operation of low-threshold and widely tunable polymer-based nanofluidic distributed feedback (DFB) dye lasers. The devices rely on light-confinement in a nanostructured polymer film embedded between two substrates. An array of nanofluidic channels forms a Bragg grating DFB laser resonator relying on the third order Bragg reflection. The lasers are fabricated by Combined Electron beam and UV Lithography (CEUL) in a thin film of SU-8 resist and polymer mediated wafer bonding. The devices are operated without the need for external fluidic handling apparatus. Capillary action drives the liquid dye infiltration of the nanofluidic DFB lasers and accounts for dye replenishment. The low Bragg reflection order yields: (i) low out-of-plane scattering losses, (ii) low coupling losses for the light when traversing the dye-filled nanofluidic channels due to the sub-wavelength dimensions of the resonator segments, and (iii) a large free spectral range (FSR). Points (i)+(ii) enable a low threshold for lasing, point (iii) facilitates wavelength tuning over the full gain spectrum of the chosen laser dye without mode-hopping. By combining different grating periods and dye solution refractive indices, we demonstrate a tuning range of 45 nm using a single laser dye and obtain laser threshold fluences down to ~ 7 ?J/mm2. The lasers are straightforward to integrate on lab-on-a-chip microsystems, e.g. for novel sensor concepts, where coherent light in the visible range is desired.

Gersborg-Hansen, Morten; Kristensen, Anders

2007-09-01

365

Fungal dye decolourization: Recent advances and future potential  

Microsoft Academic Search

Dyes released by the textile industries pose a threat to the environmental safety. Recently, dye decolourization through biological means has gained momentum as these are cheap and can be applied to wide range of dyes. This review paper focuses on the decolourization of dye wastewaters through fungi via two processes (biosorption and bioaccumulation) and discusses the effect of various process

Prachi Kaushik; Anushree Malik

2009-01-01

366

Degradation of azo dyes by environmental microorganisms and helminths  

Microsoft Academic Search

The degradation of azo dyes by environmental microorganisms, fungi, and helminths is reviewed. Azo dyes are used in a wide variety of products and can be found in the effluent of most sewage treatment facilities. Substantial quantities of these dyes have been deposited in the environment, particularly in streams and rivers. Azo dyes were shown to affect microbial activities and

King-Thom Chung; S. Edward Stevens

1993-01-01

367

Improved Charge-Transfer Fluorescent Dyes  

NASA Technical Reports Server (NTRS)

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.

Meador, Michael

2005-01-01

368

Dye Degradation by Fungi: An Exercise in Applied Science for Biology Students  

ERIC Educational Resources Information Center

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…

Lefebvre, Daniel D.; Chenaux, Peter; Edwards, Maureen

2005-01-01

369

Design of dye-sensitized solar cells with new light-harvesting dyes  

NASA Astrophysics Data System (ADS)

Phthalocyanine dyes are well known for their intense absorption in the red and near-IR regions. We synthesized novel phthalocyanines for dye-sensitized solar cell (DSSC). Those dyes can absorb in the red and near-IR regions and adsorb onto the surface of TiO II. Using such phthalocyanines as working electrode with TiO II, DSSCs were assembled and its photocurrent-voltage and IPCE characteristics have been studied and compared. Light energy conversion efficiency of DSSCs depended on the structures of phthalocyanine, the co-adsorbent, and the electrolytes. Furthermore, multi-dye type DSSC was investigated, which mixed a phthalocyanine and a carotenoid derivative. The conversion efficiency of the multi-dye DSSC increased compared with the DSSC which used single dye.

Nagata, Morio; Kimura, Mutsumi; Taya, Minoru

2008-03-01

370

Study the effect of metal ion on wool fabric dyeing with tea as natural dye  

Microsoft Academic Search

Aqueous extract of natural dye, tea was dyed on the wool fabric with dark brown for 2% and 5% shade. The tea containing tannins as the main colorant species to produce different shade with different mordant salts. The mordant salts Alum, CuSO4, FeSO4, ZnSO4, Na2SO4, and MgSO4 were used to dye fabric using three different dyeing methods: pre-mordanting, meta-mordanting and

Arsheen Moiz; M. Aleem Ahmed; Naheed Kausar; Kamran Ahmed; Munnaza Sohail

2010-01-01

371

Removal of dyes from an artificial textile dye effluent by two agricultural waste residues, corncob and barley husk  

Microsoft Academic Search

The use of a previously untried biosorbent, barley husk, for dye removal is compared to corncob. The effectiveness of adsorption as a means of dye removal has made it an ideal alternative to other more costly treatments. This paper deals with two low-cost, renewable biosorbents, which are agroindustrial by-products, for textile dye removal. Experiments at total dye concentrations of 10,

T. Robinson; B. Chandran; P. Nigam

2002-01-01

372

2,3?-diamino-4,4?-stilbenedicarboxylic acid sensitizer for dye-sensitized solar cells: quantum chemical investigations.  

PubMed

The metal-free organic dye sensitizer 2,3?-diamino-4,4?-stilbenedicarboxylic acid has been investigated for the first time for dye-sensitized solar cell applications. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations (performed using the hybrid functional B3LYP) were carried out to analyze the geometry, electronic structure, polarizability, and hyperpolarizability of 2,3?-diamino-4,4?-stilbenedicarboxylic acid used as a dye sensitizer. A TiO2 cluster was used as a model semiconductor when attempting to determine the conversion efficiency of the selected dye sensitizer. Our TD-DFT calculations demonstrated that the twenty lowest-energy excited states of 2,3?-diamino-4,4?-stilbenedicarboxylic acid are due to photoinduced electron-transfer processes. Moreover, interfacial electron transfer between a TiO2 semiconductor electrode and the dye sensitizer occurs through electron injection from the excited dye to the semiconductor’s conduction band. Results reveal that metal-free 2,3?-diamino-4,4?-stilbenedicarboxylic acid is a simple and efficient sensitizer for dye-sensitized solar cell applications. PMID:23959394

Senthilkumar, Palanivel; Nithya, Chandrasekaran; Anbarasan, Ponnusamy Munusamy

2013-10-01

373

Degradation of sulphonated azo dye Red HE7B by Bacillus sp. and elucidation of degradative pathways.  

PubMed

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

Thakur, Jyoti Kumar; Paul, Sangeeta; Dureja, Prem; Annapurna, K; Padaria, Jasdeep C; Gopal, Madhuban

2014-08-01

374

Laser-induced removal of a dye C.I. Acid Red 87 using n-type WO3 semiconductor catalyst.  

PubMed

Water contamination by organic substances such as dyes is of great concern worldwide due to their utilization in many industrial processes and environmental concerns. To cater the needs for waste water treatment polluted with organic dyes, laser-induced photocatalytic process was investigated for removal of a dye derivative namely Acid Red 87 using n-type WO3 semiconductor catalyst. The degradation was investigated in aqueous suspensions of tungsten oxide under different experimental conditions using laser instead of conventional UV lamp as an irradiation source. The degradation process was monitored by measuring the change in dye concentration as a function of laser irradiation time by employing UV spectroscopic analysis. The degradation of dye was studied by varying different parameters such as laser energy, reaction pH, substrate concentration, catalyst concentration, and in the presence of electron acceptors such as hydrogen peroxide (H2O2), and potassium bromate (KBrO3). The degradation rates were found to be strongly dependent on all the above-mentioned parameters. Our experimental results revealed that the dye degradation process was very fast (within few minutes) under laser irradiation as compared to conventional setups using broad spectral lamps (hours or days) and this laser-induced photocatalytic degradation method could be an effective means to eliminate the pollutants present in liquid phase. The experience gained through this study could be beneficial for treatment of waste water contaminated with organic dyes and other organic pollutants. PMID:19540669

Qamar, M; Gondal, M A; Hayat, K; Yamani, Z H; Al-Hooshani, K

2009-10-30

375

Chromosome characterization using single fluorescent dye  

DOEpatents

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.

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

1995-01-01

376

Polymerization of novel methacrylated anthraquinone dyes  

PubMed Central

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

Dollendorf, Christian; Kreth, Susanne Katharina; Choi, Soo Whan

2013-01-01

377

Solid state dye laser for medical applications  

NASA Astrophysics Data System (ADS)

The development of solid state dye lasers could lead to a major breakthrough in the cost and compactness of a medical device. Advantages include: elimination of the flow system for the gain medium; ease with which to implement wavelength agility or the replacement of a degraded rod or sheet; and toxicity and flammability become a non-issue. Dye lasers have played a role in cardiology, dermatology, and urology. Of these cardiology is of interest to Palomar. The Palomar Model 3010 flashlamp-pumped dye laser medical device was used during phase 1 FDA clinical trials to break-up blood clots that cause heart attacks, a process known as coronary laser thrombolysis. It is the objective of this research and development effort to produce solid matrix lasers that will replace liquid dye lasers in these medical specialties.

Aldag, Henry R.

1994-06-01

378

Determination of dyes in diesel fuels  

SciTech Connect

On November 24, 1993, the Internal Revenue Service issued a `Notice of Proposed Rule Making` relating taxation of on-road diesel fuels and policing by means of a dyeing program. Based on the proposed regulation, various qualitative and quantitative methods were developed by two laboratories to identify and determine concentration of various dyes in No. 1 and No. 2 diesel fuels. A simple qualitative method was devised which consists of extracting the dye out of the fuel and identifying dye composition by thin layer chromatography. Quantitative methods were also developed based on spectrophometric evaluation of dyed fuel. The quantitative methods are designed for use with low cost single beam spectrophometers. Independent results based on a nine terminal sampling program are included. 5 refs., 2 figs., 13 tabs.

Sweeney, E.G.; Schmidt, C.H.; Zimin, A.; Caputo, P.A.; Anderson, P.M.

1994-10-01

379

Corrosion Inhibitors as Penetrant Dyes for Radiography  

NASA Technical Reports Server (NTRS)

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.

Novak, Howard L.; Hall, Phillip B.

2003-01-01

380

Dye plants of East Anatolia Region (Turkey)  

Microsoft Academic Search

Dye plants that are commonly used by the regional people of East Anatolia were studied. The following information was collected:\\u000a local name of plants, the part of plants containing dye, obtained color, dying substances, and extraction of colors. As a\\u000a result of area investigations carried out between 1994 and 2000, 50 taxa (used for dying wool yarns in the region)

Fevzi Özgökce; ?brahim Yilmaz

2003-01-01

381

Phytoremediation in education: textile dye teaching experiments.  

PubMed

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

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

2009-07-01

382

Adsorption of basic dyes onto montmorillonite  

Microsoft Academic Search

Ca-montmorillonite (Ca-Mont) was exchanged with titanium cations and the adsorption equilibrium and kinetics of Basic Green 5 (BG5) and Basic Violet 10 (BV10) on these montmorillonites were measured to examine the ion-exchange effects on the basic dyes adsorption. The relationship between the dye adsorption and the alteration of pore structures of montmorillonite induced by ion-exchange processes was discussed. Moreover, the

Cheng-Cai Wang; Lain-Chuen Juang; Ting-Chu Hsu; Chung-Kung Lee; Jiunn-Fwu Lee; Fu-Chuang Huang

2004-01-01

383

Adsorption of basic dyes onto MCM-41  

Microsoft Academic Search

The adsorption of two basic dyes, Basic Green 5 (BG5) and Basic Violet 10 (BV10), onto MCM-41 was studied to examine the possible effect of interactions between large adsorbates and MCM-41 on the pore structure stability of MCM-41 and the potential of MCM-41 for the removal of basic dyes from wastewater. The revolutions of surface characteristics and pore structure of

Lain-Chuen Juang; Cheng-Cai Wang; Chung-Kung Lee

2006-01-01

384

ELECTROCHEMICAL REDUCTION PRIOR TO ELECTRO-FENTON OXIDATION OF AZO DYES. IMPACT OF THE PRE-TREATMENT ON  

E-print Network

; Biodegradability. 1. Introduction Industrial wastewater purification is a matter of great interest or organics. Organic dyes constitute one of the largest groups of pollutants in wastewater. Among the 1 % are released in the environment (E. Guivarch et al. 2003b). The discharge of highly coloured wastewater

Paris-Sud XI, Université de

385

Sweeteners, flavorings, and dyes in antibiotic preparations.  

PubMed

Even though a variety of adverse effects caused by sweeteners, flavorings, and dyes in susceptible individuals have been reported, there is no good single reference with information about these substances in pediatric antimicrobials. Data on sweeteners, flavorings, and dyes in 91 antimicrobial preparations were collected. Sucrose was present in 74 (85%) of 87 preparations, followed by saccharin in 30 (34%) preparations. Mannitol, lactose, and sorbitol were each present in 7 preparations. None of the preparations were free of sweeteners. Thirty-four (37%) of 91 preparations did not specify the flavoring content. While cherry was the most common flavoring used, there were 25 other flavorings. Thirteen different dyes and coloring agents were used in these antimicrobials. Red dye no. 40 was present in 45% of preparations. Tables detailing sweeteners, flavorings, and dyes in different groups of antimicrobials (amoxicillin, ampicillin, cephalosporins, erythromycin, penicillins, sulfonamides, and others) and adverse effects reported with these inert ingredients are presented. These tables should be helpful to physicians in selecting an antimicrobial containing a different sweetener and/or dye when an adverse reaction occurs. PMID:2000275

Kumar, A; Weatherly, M R; Beaman, D C

1991-03-01

386

Optical Data Storage in Acid Red Dyes  

NASA Astrophysics Data System (ADS)

High-density optical data storage is a current field gaining importance where research work is done in abundance to bring about holographic CDs to light. Dye-doped gelatin films are promising candidates as recording materials for holographic data storage because of the ease of preparation and low cost. In this report we suggest some acid red dyes as useful recording materials for optical data storage. Acid red dyes namely Acid Red 73 and Acid Red 114 that are completely water-soluble are used to sensitize gelatin thin films for data storage. These dyes have their absorption peak around 514 nm. Two coherent beams of Argon ion laser (514.5 nm) are used to form the grating in the dye-sensitized gelatin films. The grating formed is found to be permanent. The diffraction efficiency of each material as a function of different parameters like dye concentration, writing beam intensities and their ratios and spatial frequency has been studied and presented. An attempt to store data in the sample has been made.

Sankar, Deepa; Palanisamy, P. K.

387

Oxidative degradation of azo dyes using tourmaline.  

PubMed

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

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

2013-09-15

388

Improvement on the long-term stability of flexible plastic dye-sensitized solar cells  

Microsoft Academic Search

We investigate the long-term stability of performance for plastic dye-sensitized solar cells (DSSCs) based on organic iodides (TBAI or PMII) in methoxypropionitrile-based electrolytes. Plastic DSSCs containing TBAI maintain 96.9% of baseline efficiency under more than 1000h prolonged one sun light irradiation and thermal stress (60°C) aging. The factors of device long-term stability, such as the effects of organic iodides, cell-sealing

Kun-Mu Lee; Wei-Hao Chiu; Ming-De Lu; Wen-Feng Hsieh

389

Evaluation of voltage-sensitive fluorescence dyes for monitoring neuronal activity in the embryonic central nervous system  

PubMed Central

Using an optical imaging technique with voltage-sensitive dyes (VSDs), we have been investigating the functional organization and architecture of the central nervous system (CNS) during embryogenesis. In the embryonic nervous system, a merocyanine-rhodanine dye, NK2761, has proved to be the most useful absorption dye for detecting neuronal activity because of its high signal-to-noise ratio (S/N), low toxicity, and small dye bleaching. In the present study, we evaluated the suitability of voltage-sensitive fluorescence dyes for optical recording in the embryonic CNS. We screened eight styryl (hemicyanine) dyes in isolated brainstem-spinal cord preparations from 7-day old chick embryos. Measurements of voltage-related optical signals were made using a multiple-site optical recording system. The signal size, S/N, photobleaching, effects of perfusion, and recovery of neural responses after staining were compared. We also evaluated optical responses with various magnifications. Although the S/N was lower than with the absorption dye, clear optical responses were detected with several fluorescence dyes, including di-2-ANEPEQ, di-4-ANEPPS, di-3-ANEPPDHQ, di-4-AN(F)EPPTEA, di-2-AN(F)EPPTEA, and di-2-ANEPPTEA. Di-2-ANEPEQ showed the largest S/N, whereas its photobleaching was faster and the recovery of neural responses after staining was slower. Di-4-ANEPPS and di-3-ANEPPDHQ also exhibited a large S/N, but required a relatively long time for recovery of neural activity. Di-4-AN(F)EPPTEA, di-2-AN(F)EPPTEA, and di-2-ANEPPTEA showed smaller S/Ns than di-2-ANEPEQ, di-4-ANEPPS, and di-3-ANEPPDHQ, but the recovery of neural responses after staining was faster. This study demonstrates the potential utility of these styryl dyes in optical monitoring of voltage changes in the embryonic CNS. PMID:23975337

Mullah, Saad Habib-E-Rasul; Komuro, Ryo; Yan, Ping; Hayashi, Shihori; Inaji, Motoki; Momose-Sato, Yoko; Loew, Leslie M.; Sato, Katsushige

2014-01-01

390

Efficient dye-sensitized solar cells using a tetramethylthiourea redox mediator.  

PubMed

An organic redox couple tetramethylthiourea/tetramethylformaminium disulfide (TMTU/TMFDS(2+) ) is evaluated in dye-sensitized solar cells in conjunction with a series of indoline and ruthenium-based dyes. Of these, devices with indoline dye D205 show the best performance, with an optimized power conversion efficiency of 7.6?% under AM?1.5G 1?sun illumination. Charge collection and injection are highly efficient in all TMTU-based DSCs studied. Regeneration of indoline dyes is highly efficient, whereas regeneration of ruthenium dyes by TMTU is less efficient, accounting for their inferior performance. Impedance spectroscopy results reveal that using an optimized TMTU/TMFDS(2+) electrolyte solution, the TiO2 conduction band edge is 300-400?meV lower than when an optimized I3 (-) /I(-) electrolyte is used. The would-be loss in open-circuit voltage caused by the downward conduction band shift is mostly compensated by approximately the 200?meV lower redox level of the TMTU/TMFDS(2+) electrolyte and up to 1000 times slower recombination rates. This makes TMTU/TMFDS(2+) a promising redox couple in the development of highly efficient solar energy conversion devices. PMID:23929783

Liu, Yeru; Jennings, James R; Wang, Qing

2013-11-01

391

Modeling opto-electronic properties of a dye molecule in proximity of a semiconductor nanoparticle  

NASA Astrophysics Data System (ADS)

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.

Delgado, Alain; Corni, Stefano; Goldoni, Guido

2013-07-01

392

All-solid-state dye-sensitized solar cells with high efficiency.  

PubMed

Dye-sensitized solar cells based on titanium dioxide (TiO(2)) are promising low-cost alternatives to conventional solid-state photovoltaic devices based on materials such as Si, CdTe and CuIn(1-x)Ga(x)Se(2) (refs 1, 2). Despite offering relatively high conversion efficiencies for solar energy, typical dye-sensitized solar cells suffer from durability problems that result from their use of organic liquid electrolytes containing the iodide/tri-iodide redox couple, which causes serious problems such as electrode corrosion and electrolyte leakage. Replacements for iodine-based liquid electrolytes have been extensively studied, but the efficiencies of the resulting devices remain low. Here we show that the solution-processable p-type direct bandgap semiconductor CsSnI(3) can be used for hole conduction in lieu of a liquid electrolyte. The resulting solid-state dye-sensitized solar cells consist of CsSnI(2.95)F(0.05) doped with SnF(2), nanoporous TiO(2) and the dye N719, and show conversion efficiencies of up to 10.2 per cent (8.51 per cent with a mask). With a bandgap of 1.3 electronvolts, CsSnI(3) enhances visible light absorption on the red side of the spectrum to outperform the typical dye-sensitized solar cells in this spectral region. PMID:22622574

Chung, In; Lee, Byunghong; He, Jiaqing; Chang, Robert P H; Kanatzidis, Mercouri G

2012-05-24

393

Characterization of azo dyes on Pt and Pt/polyaniline/dispersed Pt electrodes  

NASA Astrophysics Data System (ADS)

The electrochemical characterization of two organic dyes (amaranth and procion orange MX-2R) has been performed on Pt electrodes and Pt electrodes coated with polyaniline and dispersed Pt. Electrodes with different Pt loads have been synthesized and characterized obtaining that a load of 300 ?g cm-2 was the optimum one. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) was employed to observe the distribution and morphology of the Pt nanoparticles. The electroactivity of the electrodes has also been characterized by means of scanning electrochemical microscopy (SECM). The chemical characterization of Pt dispersed Pani coated Pt electrodes (Pt-Pani-Pt) was performed by means of X-ray photoelectron spectroscopy (XPS). The electrochemical characterization of the dyes has been performed by means of cyclic voltammetry. Voltammograms have shown that the presence of the dyes diminishes characteristic Pt oxidation and reduction peaks. However, redox processes due to the dyes, appeared in the voltammograms. The different species responsible of these redox processes were generated in the vicinity of the electrode and were not adsorbed on the electrode surface since after stirring, the different redox processes disappeared. Characterization with different scan rates showed that redox processes of both dyes were controlled by diffusion.

Molina, J.; Fernández, J.; del Río, A. I.; Bonastre, J.; Cases, F.

2012-06-01

394

Nucleophilic Addition of Reactive Dyes on Amidoximated Acrylic Fabrics  

PubMed Central

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.

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

2014-01-01

395

Nucleophilic addition of reactive dyes on amidoximated acrylic fabrics.  

PubMed

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

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

2014-01-01

396

Dye laser amplifier including a specifically designed diffuser assembly  

DOEpatents

A large (high flow rate) dye laser amplifier in which a continuous replened supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a relatively high flow rate and a specifically designed diffuser assembly for slowing down the flow of dye while, at the same time, assuring that as the dye stream flows through the diffuser assembly it does so in a stable manner.

Davin, James (Gilroy, CA); Johnston, James P. (Stanford, CA)

1992-01-01

397

Study of the release of a microencapsulated acid dye in polyamide dyeing using mixed cationic liposomes.  

PubMed

The main objective of this work was to increase the retarding effect of the acid dye Telon(®) Blue RR (C.I. Acid Blue 62; DyStar, Frankfurt, Germany) release on polyamide fibres dyeing by encapsulation of the dye in liposomes as an alternative to synthetic auxiliaries, in order to reduce effluent pollution. The retarding effect achieved with the use of mixed cationic liposomes of dioctadecyldimethylammonium bromide (DODAB)/soybean lecithin (containing a 10% molar fraction of DODAB) was better in comparison with either pure soybean lecithin liposomes or synthetic auxiliaries. The retarding effect of liposomes on the dye release was analysed through changes in the absorption and fluorescence spectra of the acid dye at different conditions. The effect of temperature (in the range of 25 °C - 70 °C) on the spectroscopic behaviour of the dye in the absence and in presence of polyamide was also studied, in order to simulate the dyeing conditions. Exhaustion curves obtained in dyeing experiments showed that, below 45 °C, the retarding effect of the mixed liposomes (lecithin/DODAB (9:1)) was similar to that of the auxiliaries, but better than the one of pure lecithin liposomes. At higher temperatures (above 45 °C), the system lecithin/DODAB presents a better performance, achieving a higher final exhaustion level when compared with the commercial leveling agent without losing the smoothing effect of lecithin. PMID:20550462

de Sousa, Isabel S C; Castanheira, Elisabete M S; Rocha Gomes, Jaime I N; Real Oliveira, M Elisabete C D

2011-06-01

398

Dyeing and antimicrobial characteristics of chitosan treated wool fabrics with henna dye  

Microsoft Academic Search

Chitosan, a naturally available biopolymer which is now increasingly being used as a functional finish on textile substrates to impart antimicrobial characteristics and increase dye uptake of fabrics was applied on wool fabrics. Henna a natural dye with proven bactericidal properties was applied on wool fabrics along with chitosan to impart antimicrobial characteristics. The effect of chitosan application on the

V. R. Giri Dev; J. Venugopal; S. Sudha; G. Deepika; S. Ramakrishna

2009-01-01

399

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...

400

WASTES FROM MANUFACTURE OF DYES AND PIGMENTS. VOLUME 5. DIPHENYLMETHANE AND TRIARYLMETHANE DYES AND PIGMENTS  

EPA Science Inventory

A preliminary study of the manufacture of diphenylmethane and triarylmethane dyes 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 produc...

401

Rapid Double-Dye-Layer Coating for Dye-Sensitized Solar Cells using a New Method.  

PubMed

Intensive research with the specific aim of developing inexpensive renewable energy sources is currently being undertaken. In dye-sensitized solar cell (DSSC) production, the most time-consuming process is coating the dye on working electrodes: absorption of ruthenium-based dyes [e.g., N719=bis(trtrabutylammonium)-cis-di(thiocyanato)-N,N'-bis(4-carboxylato-4'-carboxylic acid-2,2'-bipyridine) ruthenium(II)] on a photoanode takes a long time. We report a simple dye-coating method using a mixed solvent of ethylene glycol (EG) and glycerol (Gly). According to our experiments, dye-coating time can be reduced to 5?min from several hours. Maximum performance was obtained with an EG/Gly ratio of 1:1. This mixture of solvents gave a performance of 9.1?%. Furthermore, the viscous solvent system could control coating depth; positioning dye coatings to a specific depth was rapid and facile. A cell containing two different dyes (N719+black dye) had an efficiency of 9.4?%. PMID:25154611

Jung, Cho-Long; Han, Chi-Hwan; Moon, Doo Kyung; Jun, Yongseok

2014-10-01

402

Titania nanobundle networks as dye-sensitized solar cell photoanodes  

NASA Astrophysics Data System (ADS)

Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (? = 6.1 +/- 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (? = 6.3 +/- 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3]2+/3+ redox couple and the MK2 organic sensitizer resulted in higher efficiencies (? = 7.70 +/- 0.1%) than for the P25 devices (? = 6.3 +/- 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency.Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (? = 6.1 +/- 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (? = 6.3 +/- 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3]2+/3+ redox couple and the MK2 organic sensitizer resulted in higher efficiencies (? = 7.70 +/- 0.1%) than for the P25 devices (? = 6.3 +/- 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr06157d

Dong, Cunku; Xiang, Wanchun; Huang, Fuzhi; Fu, Dongchuan; Huang, Wenchao; Bach, Udo; Cheng, Yi-Bing; Li, Xin; Spiccia, Leone

2014-03-01

403

Photocatalytic Degradation of Azo Dyes using Doped Titania Fibers  

NASA Astrophysics Data System (ADS)

Photo-catalytic degradation using semiconductor particle as dispersion in aqueous medium has been gaining increased attention over the past several years. Their versatility in application makes them unique along with their easy processing techniques and low cost. Titania semiconductor is one of the most important members of this family. It has been widely used for various applications ranging from environmental to bio-medical. Titanium dioxide has gained importance as an effective photo-catalyst because of its advantages over other semiconductor oxides which include high photo-stability, inexpensive, reusable property, chemical and biological inertness, high reactivity, non-toxicity, corrosion resistance, operation at ambient temperatures and its ability to treat trace level pollutants. Its use as a photocatalyst is primarily because of its band gap of 3.0-3.3 eV which can be effectively activated under ultraviolet radiation (wavelength lambda < 400 nm), which leads to electron jump from valence to conduction band. This project aims at developing electrospun titania fibers doped with copper in order to study and demonstrate photocatalytic activity in the visible light spectrum, resulting in quick formation of holes which are ready to react with water to form -OH radicals. A comparative study of pure titania and copper doped titania for degradation of azo dyes were carried out. SEM, EDAX, XRD were carried out to thoroughly understand the structure of the fibers. The photocatalytic activity measurements for different dyes were noted using Uv-Vis method. The fibers when fully developed will be disposable photocatalytic materials for degrading dyes, Organic pollutants and for bio-medical applications when exposed to visible light.

Shanmugasundaram, Prasad

404

Metals Verification Study for Sinclair and Dyes Inlets,Washington  

SciTech Connect

Sinclair and Dyes Inlets near Bremerton, Washington, are on the State of Washington's 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. This Metals Verification Study was conducted to address the 303(d) segments that are listed for metal contaminants in marine sediment, because significant cleanup and source control activities have been conducted in the Inlets since the data supporting the 1998 303(d) listings were collected. The study was designed to obtain present-day sediment metals concentrations throughout Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage, with stations spatially distributed to support 303(d) listing updates and also watershed-level water quality and contaminant transport modeling efforts. A total of 160 surface sediment samples from Sinclair Inlet, Dyes Inlet, Port Orchard Passage, and Rich Passage were screened for copper, lead, and zinc using X-Ray Fluorescence (XRF). 40 samples (25%) were selected for confirmatory metals analysis by ICP-MS for cadmium, silver, and arsenic in addition to copper, lead, and zinc. Regression relationships between the ICP-MS and XRF datasets were developed to estimate copper, lead, and zinc concentrations in all samples. The XRF results for copper, lead, and zinc correlated well with ICP-MS results, and predicted concentrations were calculated for all samples. The results of the Metals Verification Study show that sediment quality in Sinclair Inlet has improved markedly since implementation of cleanup and source control actions, and that the distribution of residual contaminants is limited to nearshore areas already within the actively managed Puget Sound Naval Shipyard Superfund Site where further source control actions and monitoring are under way. Outside of Sinclair Inlet, the target metals met state sediment quality standards.

Kohn, Nancy P.; Miller, Martin C.; Brandenberger, Jill M.; Johnston, Robert K.

2004-09-29

405

Tunability of optofluidic distributed feedback dye lasers  

NASA Astrophysics Data System (ADS)

We investigate the tunability of optofluidic distributed feedback (DFB) dye lasers. The lasers rely on light-confinement in a nano-structured polymer film where an array of nanofluidic channels constitutes a third order Bragg grating DFB laser resonator with a central phase-shift. The lasers are operated by filling the DFB laser resonator with a dye solution by capillary action and optical pumping with a frequency doubled Nd:YAG laser. The low reflection order of the DFB laser resonator yields low out-of-plane scattering losses as well as a large free spectral range (FSR), and low threshold fluences down to ~7 µJ/mm2 are observed. The large FSR facilitates wavelength tuning over the full gain spectrum of the chosen laser dye and we demonstrate 45 nm tunability using a single laser dye by changing the grating period and dye solution refractive index. The lasers are straight-forward to integrate on lab-on-a-chip microsystems, e.g. for novel sensor concepts, where coherent light in the visible range is desired.

Gersborg-Hansen, Morten; Kristensen, Anders

2007-01-01

406

Solvatochromic behavior of some ?-styrylpyridinium dyes.  

PubMed

The influences of solvent polarity and substituent on the electronic transition of six different N-butyl-?-styrylpyridinium dyes have been investigated in 21 solvents. Reichardt's E(T)(30) scale has been used to propose a quantitative approach towards the relative stability of the electronic ground and excited state species. The solvents have been classified into three types and the dyes have been classified into four groups based on the contribution of field and inductive effects of the substituents towards the change in their absorption maxima values. Instead of a steady solvatochromism, all the dyes except p-nitro substituted one, suffer reversals in solvatochromism at E(T)(30) values of ~37 and ~48. The extents of contribution of non-polar and polar protic solvents towards the solvation of the excited states of the dye molecules have been determined to be 30-40% more than that towards the stability of their ground states by the dipolar aprotic solvents. The ortho effect shown by this class of dyes in contrast to their corresponding ?-isomers might have been responsible for their better solvent polarity sensing capability. PMID:24568791

Tripathy, Sarita; Guru, Partha Sarathi; Dash, Sukalyan

2014-05-01

407

Solvatochromic behavior of some ?-styrylpyridinium dyes  

NASA Astrophysics Data System (ADS)

The influences of solvent polarity and substituent on the electronic transition of six different N-butyl-?-styrylpyridinium dyes have been investigated in 21 solvents. Reichardt’s ET(30) scale has been used to propose a quantitative approach towards the relative stability of the electronic ground and excited state species. The solvents have been classified into three types and the dyes have been classified into four groups based on the contribution of field and inductive effects of the substituents towards the change in their absorption maxima values. Instead of a steady solvatochromism, all the dyes except p-nitro substituted one, suffer reversals in solvatochromism at ET(30) values of ˜37 and ˜48. The extents of contribution of non-polar and polar protic solvents towards the solvation of the excited states of the dye molecules have been determined to be 30-40% more than that towards the stability of their ground states by the dipolar aprotic solvents. The ortho effect shown by this class of dyes in contrast to their corresponding ?-isomers might have been responsible for their better solvent polarity sensing capability.

Tripathy, Sarita; Guru, Partha Sarathi; Dash, Sukalyan

408

Efficient p-type dye-sensitized solar cells based on disulfide/thiolate electrolytes  

NASA Astrophysics Data System (ADS)

Herein, an organic redox couple 1-methy-1H-tetrazole-5-thiolate (T-) and its disulfide dimer (T2) redox shuttle, as an electrolyte, is introduced in a p-type dye-sensitized solar cell (DSC) on the basis of an organic dye (P1) sensitizer and nanocrystal CuCrO2 electrode. Using this iodide-free transparent redox electrolyte in conjunction with the sensitized heterojunction, we achieve a high open-circuit voltage of over 300 mV. An optimal efficiency of 0.23% is obtained using a CoS counter electrode and an optimized electrolyte composition under AM 1.5 G 100 mW cm-2 light illumination which, to the best of our knowledge, represents the highest efficiency that has so far been reported for p-type DSCs using organic redox couples.Herein, an organic redox couple 1-methy-1H-tetrazole-5-thiolate (T-) and its disulfide dimer (T2) redox shuttle, as an electrolyte, is introduced in a p-type dye-sensitized solar cell (DSC) on the basis of an organic dye (P1) sensitizer and nanocrystal CuCrO2 electrode. Using this iodide-free transparent redox electrolyte in conjunction with the sensitized heterojunction, we achieve a high open-circuit voltage of over 300 mV. An optimal efficiency of 0.23% is obtained using a CoS counter electrode and an optimized electrolyte composition under AM 1.5 G 100 mW cm-2 light illumination which, to the best of our knowledge, represents the highest efficiency that has so far been reported for p-type DSCs using organic redox couples. Electronic supplementary information (ESI) available: Optimization of electrolyte concentration and the solvent used in the experiment, and the effects of different redox couples and the counter electrode on the dark current. See DOI: 10.1039/c3nr02169f

Xu, Xiaobao; Zhang, Bingyan; Cui, Jin; Xiong, Dehua; Shen, Yan; Chen, Wei; Sun, Licheng; Cheng, Yibing; Wang, Mingkui

2013-08-01

409

Refractive keratoplasty. Tissue dyes and cryoprotective solutions.  

PubMed

The cryoprotective dye solution KM-26 (0.25% kiton green, 8% glycerin, and 4% dimethyl sulfoxide), which is presently used for all lamellar refractive surgical procedures, was evaluated and compared to other dyes that can stain corneal tissue. With the use of canine and human eye bank tissue, we found kiton green and light green to produce the least tissue alteration and to destain readily. Glycerin with or without dimethyl sulfoxide or dye was deleterious to the endothelium in the area under the keratectomized recipient bed. On the basis of our findings, glycerin and dimethyl sulfoxide should be deleted from the cryoprotective solution and a 0.1% concentration of light green in balanced salt solution or M-K medium should be used and the frozen tissue should be thawed in a balanced salt solution or M-K medium to eliminate potential damage to the recipient corneal endothelium. PMID:6354158

Binder, P S; Zavala, E Y; Deg, J; Akers, P H

1983-10-01

410

Nonlinear optical properties of multipyrrole dyes  

NASA Astrophysics Data System (ADS)

The nonlinear optical properties of a series of pyrrolic compounds consisting of BODIPY and aza-BODIPY systems are investigated using 532 nm nanosecond laser and the Z-scan technique. Results show that 3,5-distyryl extension of BODIPY to the red shifted MeO2BODIPY dye has a dramatic impact on its nonlinear absorption properties changing it from a saturable absorber to an efficient reverse saturable absorbing material with a nonlinear absorption coefficient of 4.64 × 10-10 m/W. When plotted on a concentration scale per mole of dye in solution MeO2BODIPY far outperforms the recognized zinc(II) phthalocyanine dye and is comparable to that of zinc(II) tetraphenylporphyrin.

Frenette, Mathieu; Hatamimoslehabadi, Maryam; Bellinger-Buckley, Stephanie; Laoui, Samir; Bag, Seema; Dantiste, Olivier; Rochford, Jonathan; Yelleswarapu, Chandra

2014-07-01

411

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

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

412

The Ideal Solvent for Paper Chromatography of Food Dyes.  

ERIC Educational Resources Information Center

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)

Markow, Peter G.

1988-01-01

413

Microfluidic Investigation of Tracer Dye Diffusion in Alumina Nanofluids  

E-print Network

. Under conditions matching previously reported studies, strong complexation interactions between the dye and nanoparticles at the interface between fluid streams was observed. When the tracer dye and surfactant were carefully chosen to minimize...

Ozturk, Serdar 1979-

2012-10-05

414

Water-soluble benzophenoxazine dyes: syntheses, derivatization and photophysical studies  

E-print Network

A set of three benzophenoxazine dyes, two completely soluble and one partially soluble in aqueous media, has been prepared and their spectroscopic properties examined. These dyes can be used as either donor or acceptor in synthesis of through...

Jose, Jiney

2007-04-25

415

1. Pamorana of Daniel F. Waters Germantown Dye Works site ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Pamorana of Daniel F. Waters Germantown Dye Works site (with the former Hinckley Knitting Mills in the foreground) from Germantown Avenue looking east. - Daniel F. Waters Germantown Dye Works, 37-55 East Wister Street, Philadelphia, Philadelphia County, PA

416

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2012 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2012-04-01

417

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2013-04-01

418

21 CFR 864.1850 - Dye and chemical solution stains.  

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2014-04-01

419

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2011 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2011-04-01

420

21 CFR 864.1850 - Dye and chemical solution stains.  

Code of Federal Regulations, 2010 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Biological Stains § 864.1850 Dye and chemical solution stains. (a) Identification. Dye and...

2010-04-01

421

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

NASA Astrophysics Data System (ADS)

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.

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

2013-10-01

422

Organic Dye Behavior in PEG Block Copolymer Nanoparticles  

E-print Network

://www.axxora.com/files/formula/610- 028.gif http://img.alibaba.com/photo/50521181/Natural_Vitamin_ E_Acid_Succinate.jpg DCC / THF 7 for nanoparticles Block copolymers have two components Hydrophilic and hydrophobic During nanoparticle synthesis-amino-4- methylcoumarin (AMC)- vitamin E succinate conjugate + #12;Making nanoparticles Confined

Petta, Jason

423

Organic Dyes, Conjugation, and the Chemistry of Vision  

E-print Network

()1( )1. Bond order = (3-1)/2 = 1 E=h C-C #12;Light The spectrum of white light is obtained when white light is dispersed through a prism UV IR remember ROY G BIV #12;Two 700 Red Green Shine white light on a yellow solution and yellow light gets through: Shine

Amar, François G.

424

Biodegradation and detoxification potential of rotating biological contactor (RBC) with Irpex lacteus for remediation of dye-containing wastewater.  

PubMed

Use of fungal organisms in rotating biological contactors (RBC) for bioremediation of liquid industrial wastes has so far been limited in spite of their significant biodegradation potential. The purpose was to investigate the power of RBC using Irpex lacteus for decolorization and detoxification of industrial dyes and dyeing textile liquors. Recalcitrant dye Methylene Blue (150 mg L(-1)) was decolorized within 70 days, its mutagenicity removed, and the biological toxicity decreased more than 10-fold. I. lacteus biofilm in the RBC completely decolorized within 26 and 47 days dyeing liquors containing disperse or reactive dyes adjusted to pH4.5 and 5-fold diluted with the growth medium, respectively. Their respective biological toxicity values were reduced 10- to 10(4)-fold in dependence of the test used. A battery of toxicity tests comprising Vibrio fisheri, Lemna minor and Sinapis alba was efficient to monitor the toxicity of textile dyes and wastewaters. Strong decolorization and detoxification power of RBC using I. lacteus biofilms was demonstrated. PMID:24210510

Malachova, Katerina; Rybkova, Zuzana; Sezimova, Hana; Cerven, Jiri; Novotny, Cenek

2013-12-01

425

Counterion-enhanced cyanine dye loading into lipid nano-droplets for single-particle tracking in zebrafish.  

PubMed

Superior brightness of fluorescent nanoparticles places them far ahead of the classical fluorescent dyes in the field of biological imaging. However, for in vivo applications, inorganic nanoparticles, such as quantum dots, are limited due to the lack of biodegradability. Nano-emulsions encapsulating high concentrations of organic dyes are an attractive alternative, but classical fluorescent dyes are inconvenient due to their poor solubility in the oil and their tendency to form non-fluorescent aggregates. This problem was solved here for a cationic cyanine dye (DiI) by substituting its perchlorate counterion for a bulky and hydrophobic tetraphenylborate. This new dye salt, due to its exceptional oil solubility, could be loaded at 8 wt% concentration into nano-droplets of controlled size in the range 30-90 nm. Our 90 nm droplets, which contained >10,000 cyanine molecules, were >100-fold brighter than quantum dots. This extreme brightness allowed, for the first time, single-particle tracking in the blood flow of live zebrafish embryo, revealing both the slow and fast phases of the cardiac cycle. These nano-droplets showed minimal cytotoxicity in cell culture and in the zebrafish embryo. The concept of counterion-based dye loading provides a new effective route to ultra-bright lipid nanoparticles, which enables tracking single particles in live animals, a new dimension of in vivo imaging. PMID:24661553

Kilin, Vasyl N; Anton, Halina; Anton, Nicolas; Steed, Emily; Vermot, Julien; Vandamme, Thierry F; Mely, Yves; Klymchenko, Andrey S

2014-06-01

426

New analogues of the BODIPY dye PM597: photophysical and lasing properties in liquid solutions and in solid polymeric matrices.  

PubMed

New tailormade BODIPY dyes have been synthesized by a simple protocol to reach wavelength finely tunable laser action from 540 to 625 nm while maintaining highly efficient and photostable laser emission. The new dyes are analogues of the commercial dye PM597 with the eight position free (PTH8) or substituted by the groups acetoxymethyl (PTAlk) or p-acetoxymethylphenyl (PTAr). The photophysical properties strongly depend on the geometrical distortion from planarity of the indacene core generated by the presence of the bulky 2,6-di-tert-butyl groups and the eight substituent. In both liquid and polymeric solid solutions, lasing efficiencies of up to 63 and 48%, respectively, were observed under transversal pumping at 532 nm with high photostabilities. In the case of PTAlk incorporated into silicon-containing solid organic matrices, the laser emission remained at 92% of its initial intensity value after 100,000 pumping pulses in the same position of the sample at 30 Hz repetition rate. The laser action of the new dyes enhances that of the parent dye PM597 and outperforms the lasing behavior of dyes considered to be benchmarks over the green-yellow to red spectral region. PMID:19537816

Costela, A; García-Moreno, I; Pintado-Sierra, M; Amat-Guerri, F; Sastre, R; Liras, M; López Arbeloa, F; BañuelosPrieto, J; López Arbeloa, I

2009-07-16

427

Investigating fluorescent dyes in fluorescence-assisted screenings.  

PubMed

Screening of bead-based peptide libraries against fluorescent dye-labeled target proteins was found to be significantly influenced by the dye characteristics. Commercially available red fluorescent 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 fluorescent probe for acquisition of reliable results in various fluorescence-assisted applications. PMID:25340456

Jee, Joo-Eun; Lim, Jaehong; Hyun, Hoon; Oon, Jessica; Ong, Yong Siang; Massif, Cedrik; Chang, Young-Tae; Choi, Hak Soo; Lee, Su Seong

2014-11-01